All posts by Leo Guo

About Leo Guo

Leo Guo is an avid aviation enthusiast based in West Vancouver, Canada. Having a particular interest in German and Chinese aviation, Leo has contributed numerous articles for Plane Encyclopedia, of which he holds the position of team manager, head writer and co-owner.

Nakajima Ki-43 Hayabusa in Communist Chinese Service

PRC flag People’s Republic of China (1945-1952)
Fighter – 8+ Operated

An illustration depicting a Hayabusa in Communist service flying. (Encyclopedia of Chinese Aircraft: Volume 2)

Widely known as one of Japan’s most iconic aircraft of the Pacific War, the Nakajima Ki-43 Hayabusa’s service life was not limited to the Second World War. Shortly after the Japanese capitulation, Nationalist and Communist Chinese forces were able to capture stockpiles of firearms, tanks and planes left over by the fleeing Japanese forces. Among these were various models of the Nakajima Ki-43 Hayabusa. These were pressed into service with the Communist Chinese as an advanced combat trainer and fighter. One of the rather obscure chapters of the Hayabusa’s service life was that it was the first plane used by the Communist Chinese in aerial combat.

History

Developed in the late 1930s, the Nakajima Ki-43 Hayabusa (Type 1 Fighter) enjoyed a relatively successful service record in the Second Sino-Japanese War once introduced in 1941. The Japanese 59th and 64th Sentai (Squadrons) were the first two squadrons to receive the new Ki-43-I fighter. With barely any resistance by the Republic of China Air Force (ROCAF), the Ki-43-I helped reinforce Japanese aerial superiority over China, French Indochina, Malaya, and parts of India until the arrival of lend-lease Allied warplanes for China. Throughout the service of the Hayabusa, three major variants were issued to units: the Ki-43-I, Ki-43-II, and Ki-43-III. The Japanese also provided some of these variants to the Manchukuo Imperial Air Force in the Northeast region of China. With the end of the Second Sino-Japanese War, stockpiles of Japanese equipment was up for grabs between the Soviets, Nationalist Chinese, and the Communist Chinese. The Nationalist Chinese forces reoccupied Shanghai near the end of 1945 and captured warplanes formerly belonging to the Japanese. Among these were various models of the Hayabusa which were used to equip the 18th and 19th Squadrons of the ROCAF’s 6th Fighter Group. These Hayabusas were stationed at Shandong in preparation for the Chinese Civil War. Due to a lack of spare parts and adequate mechanics, the two squadrons were disbanded the following May.

The Communist Chinese forces were by no means idle during the immediate few postwar months. Countless guns were captured, with a considerable amount of tanks and planes as well. In October of 1945, the Communist Chinese forces captured their first five Hayabusas during the liberation of Shenyang during the Liaoshen Campaign from the Nationalists. These five captured Nationalist Hayabusas were Ki-43-II models that formerly belonged to the Japanese 4th Training Regiment. The exact model of the planes is unknown. (It is unknown if they are kō, otsu, hei, etc. variants). These five planes would be sent to the recently established Northeast Old Aviation School (东北老航校) after some refurbishing and repairs. In December of the same year, two of these planes were repaired and were planned to be ferried to the Northeast Old Aviation School. Two Japanese ferry pilots now loyal to the Communist Chinese took off from Fengjibao (奉集堡) to fly to Tonghua (通化), one of their destinations. The two Hayabusas and their pilots never made it to Tonghua however, and it is widely speculated that these Japanese pilots were unfamiliar with the geography and ended up getting lost. This is indeed a possibility but there are many other theories. It’s conceivable that the planes suffered from mechanical failure and crashed. Another possibility may be that the pilots were intercepted by ROCAF planes, but there is no proof of this.

Artwork Depicting a Ki-43 flying over Japanese trainers in the Northeast Aviation School. (Illustration by Chen Yingming / 陈应明)

The rest of the Hayabusas were eventually delivered to the Northeast Old Aviation School, where they were used as advanced trainers for fighter pilots. In April of 1948, men belonging to the Northeast Old Aviation school were able to capture an unspecified amount of Hayabusa fighters in the Chaoyang (朝阳镇) Town airport located in Jilin. This was followed by another unspecified batch of Hayabusas captured in Sunjia (孙家) Airport located near Harbin in the Heilongjiang province sometime in June of the same year. Four Hayabusas were recorded to have been repaired by the school from 1947 to 1948. Under the guidance of former Japanese and Manchukuo pilots, many of the Communist Chinese air cadets were soon able to graduate from flying in the two-seater Tachikawa Ki-55 trainer to flying solo in the Hayabusa.

In March of 1948, a number of experienced pilots and instructors were pulled from the school to form a “Combat Flying Wing” (战斗飞行大队). The 1st Squadron would use bombers and transport aircraft while 2nd Squadron would use fighters. Among these would be six Ki-43-II models. The intent of this formation was to combat Nationalist planes, but this wing never saw any combat action.

Considerations were made to use the Hayabusa in the Establishment of the People’s Republic of China parade on October 1st of 1949, but this did not happen. Despite what one may think, the Japanese planes were not withheld from the parade due to political and racial issues, but rather fear of them experiencing mechanical problems during the parade.

Communist Chinese service members standing in front of a captured Hayabusa. (Encyclopedia of Chinese Aircraft: Volume 2)

As such, these worn out Hayabusas were grounded. By November of 1949, there were only five examples of the Hayabusa that were still in use. These final five fighters were used by the 7th Aviation School as trainers and teaching aids. By 1952, all of the Hayabusas were finally retired from service. There are no surviving examples of the Communist Chinese Hayabusa, but there is one known photo of the Communist Hayabusa in service.

First Air-to Air Combat of the Communist Chinese Air Force

In the afternoon of October 15th 1947, four Nationalist Chinese P-51D Mustangs belonging to the Shenyang Beiling airfield took off under the leadership of Xu Jizhen (徐吉骧), the co-captain of the squadron. They were tasked with the mission of patrolling the airspace of Harbin (哈尔滨), Jiamusi (佳木斯) and the Sino-Soviet border. Upon crossing the mountains near Mishan (密山), the Mustangs squadron noticed a Tachikawa Ki-55 trainer with Communist Chinese markings belonging to the Northeast Old Aviation School preparing to land at the nearby Tangyuan (汤原) airport. This Ki-55 was piloted by Lu Liping (吕黎平) and an unnamed Japanese instructor. Xu Jizhen immediately dove for the trainer and began firing. The area immediately behind the instructor’s compartment was hit, which resulted in a fire. Watching the attack from the ground, Fang Hua (方华), a veteran Communist soldier, scrambled for a nearby parked Nakajima Ki-43-II Hayabusa and took off. Unfortunately for him, the Hayabusa was not loaded with ammunition so he was unable to engage the Mustangs. However, he was able to lead the Mustangs away from the airfield and evaded their shots until they ran out of ammo. This unfortunate skirmish was the first air-to-air combat experience the Communist Chinese had.

Debunking the Numbers Operated

According to many Western sources, the Communist Chinese Forces only operated five Hayabusas. This is however incorrect. The author believes the reason that these sources mention only five models captured was due to translation errors or simply by overlooking facts. The most likely cause of the misconception is likely due to two facts:

  1. By the end of the Liaoshen Campaign, the Communist Chinese forces had captured five models.
  2. By the time the PLAAF was officially established, there were five models still in service.

What these Western sources may have overlooked however, was the fact that two of the first five models captured crashed during a ferry flight in December of 1945. This leaves only three models operational.

However, a commonly overlooked fact is that the Northeast Old Aviation School was able to capture an unspecified amount of Hayabusas in the Chaoyang (朝阳镇) Town airport located in Jilin sometime in April of 1946. Another unspecified batch of Hayabusas were also captured in Sunjia (孙家) Airport located near Harbin in the Heilongjiang province in June. Due to the unspecified nature of the amount of Hayabusas captured in these two places, it only adds to the difficulty of determining how much Hayabusas were truly captured and operated. But on an inventory check done in April of 1948, a total of six Hayabusas were accounted for serving with the 2nd Squadron. According to this record, that should mean three or more Hayabusas were captured in those two airfields. That should make a total of eight or more Hayabusas when accounting for the two crashed ones. In conclusion, the author believes that a potential total of eight or more Hayabusas were captured, and operated by the Communist Chinese forces to some extent until the retirement of all models in 1952.

Gallery

Communist Chinese Ki-43-II in the colors of the Northeast Old Aviation School by Brendan Matsuyama

Sources

Gang, W., Ming, C. Y., & Wei, Z. (2012). 中国飞机全书 (Vol. 1). Beijing: 航空工业出版社., Gang, W., Ming, C. Y., & Wei, Z. (2009). 中国飞机全书 (Vol. 2). Beijing: 航空工业出版社., Allen, K. (n.d.). PEOPLE’S LIBERATION ARMY AIR FORCE ORGANIZATION., 网易军事. (2016, May 24). 老航校70周年:“鬼子飞行员”在中国当教官., Zhang, X. (2003). Red Wings over the Yalu: China, the Soviet Union, and the Air War in Korea. College Station: Texas A & M University Press., Side Profile Views by Brendan Matsuyama

North American P-51 Mustang in Communist Chinese Service

PRC flag People’s Republic of China (1948-1953)
Fighter – 39 Operated

The North American P-51 Mustang is considered one of the world’s most iconic warplanes from the Second World War, seeing action in nearly all theaters, as well as the Korean War and many other conflicts thereafter. However, one of the lesser known stories of the Mustang is its service with the Communist Chinese forces who would go on to form the People’s Republic of China shortly after. A total of 39 Mustangs were obtained from the Chinese Nationalist forces either by capture or defection. These Mustangs were used in various roles with the Communists, and nine of them even had the honor of flying over Beijing on October 1st 1949 for a parade to commemorate the establishment of the People’s Republic of China. Although never seeing combat, the Mustangs still had served with the Communist Chinese forces as one of their most advanced fighters until the arrival of Soviet aid.

A photo displaying the rather impressive cache of captured Nationalist planes now in Communist service. In this photo, there are around nineteen P-51 Mustangs visible. (Encyclopedia of Chinese Aircraft: Volume 2)

History

The Republic of China (i.e, Chinese Nationalists under Generalissimo Chiang Kai-shek) was a notable operator of the North American P-51 Mustang during the Second Sino-Japanese War (1937-1945). Since the United States entered the Second World War, plans were made to provide the Republic of China China with modern American warplanes to replace the worn and outdated planes that the Republic of China Air Force (ROCAF) were using. The Mustangs were initially flown by pilots of the Chinese-American Composite Wing (CACW) starting from November 1944. The models they operated were P-51B and P-51C, but later in February 1945, P-51D and P-51K variants were delivered and put to use against the Japanese along with the P-51B and P-51C. At the end of the Second World War, the ROCAF received 278 Mustangs from the USAAF, most of which were P-51D and P-51K models, but also with some F-6D and F-6K photo reconnaissance models. Soon after, the uneasy relationship between the Communist Party of China under the leadership of Mao Zedong and the Nationalist government under the leadership of Jiang Jieshi (Chiang Kai-shek) disintegrated. As such, the civil war between the two parties resumed after nearly nine years of truce. This time however, the Communist forces were more prepared to fight the Nationalist forces. As time went on, the Nationalist forces began losing their hold on mainland China and were forced to retreat to Formosa (Taiwan), but not before many of their soldiers, officers and generals defected, leaving a substantial amount of equipment behind.

The People’s Liberation Army obtained their first Mustang on September 23rd 1948 when Captain Yang Peiguang (杨培光) from the Nationalist 4th Fighter Wing based in Beiping (Beijing) defected with his P-51D to the Communist forces at Siping, Jilin Province. The bulk of the Mustangs which would be captured by the Communist forces were, however, from the Liaoshen Campaign which lasted from September 12th – November 2nd, 1948. With the Communist victory at the Battle of Jinzhou on October 15th, a considerable amount of Nationalist equipment was captured; among these were thirty one Mustangs in various states of repair at the Jinzhou Airfield. Though now with thirty four Mustangs in total, the People’s Liberation Army was not able to press any into service due to many factors; the most important two being the lack of able pilots and the varying states of disrepair that the Mustangs were in.

The city of Shenyang was finally captured by the People’s Liberation Army on October 30th 1948, and on the second day of the city’s capture on October 31st, the Northeast People’s Liberation Army Aviation School sent men to secure the Shenyang Beiling airport, factories, warehouses, personnel, and various other assets formerly belonging to the Nationalists. In November, the Shenyang Beiling airport was officially established as the People’s Liberation Army Air Force Repair Factory Number 5 (中国人民解放军空军第五修理厂). With the establishment of this repair factory, the first machines to be repaired were the Mustangs. The repairs took top priority and the first Mustang was ready for service on December 30th. Since then, thirty six Mustangs were repaired within a span of eighteen to twenty months lasting until 1950.

On December 10th 1948, the People’s Liberation Army was able to capture the Nationalist-held Beiping (Beijing) Nanyuan Airport as part of the Pingjin Campaign. Three Mustangs were found in relatively good condition, and a total of 128 Packard-built V-1650 Merlin engines were captured as well. This boosted the total amount of Mustangs in the People’s Liberation Army to thirty seven, and provided plenty of replacement engines for maintenance. After this, two more Mustangs would fall in the hands of the Communist forces.

On December 29th, Lieutenant Tan Hanzhou (谭汉洲) of the Nationalist 4th Fighter Group defected with his Mustang from Qingdao to Communist held Shenyang. The last Mustang to fall into the People’s Liberation Army’s hands occured on January 14th of 1949 when Lieutenant Yan Chengyin* (阎承荫) from the Nationalist 3rd Fighter Group’s 28th Squadron defected from his home base of Nanjing to Communist held Jinan.

Lieutenant Tan Hanzhou with his Mustang shortly after his defection. (blog.163.com)

 

Now with thirty nine Mustangs in total, the People’s Liberation Army began to put them to use. Starting from late January 1949, a large number of Mustangs were presented to the Northeast Old Aviation School’s (东北老航校) 2nd Squadron of the 1st Air Group with the purpose of training pilots. On August 15th 1949, the People’s Liberation Army formed their first flying squadron named at the Beiping Nanyuan airfield. The squadron consisted of two Fairchild PT-19 trainers, two de Havilland Mosquito fighter-bombers and six Mustangs. Shortly after the formation on September 5th, this squadron was assigned the task of defending Beiping’s airspace from Nationalist forces. At some point before October, eleven more Mustangs were assigned to this squadron. The squadron saw no combat.

* Mr. Yan later changed his name to Yan Lei (阎磊) after his defection.

Perhaps the most notable use of the Mustangs in Communist Chinese service was on October 1st 1949. By then, the bulk of the Nationalist forces were in discord and in the process of retreating to Formosa (Taiwan). With the Communist victory inevitable, Mao Zedong proclaimed the establishment of the People’s Republic of China. A Soviet-style military parade was held in newly-renamed Beijing’s (Beiping) Tiananmen Square which included sixteen thousand and four hundred soldiers, one hundred and fifty two tanks, two hundred and twenty two cars and seventeen planes were displayed to the public. Of these seventeen planes, nine were Mustangs. The Mustangs flew in groups of threes in a V formation and led the aerial convoy. Once over Tiananmen square, these Mustangs increased their speed and flew past the square and out of sight, they made a turn and reentered Tiananmen square for the back just in time to link up with the two Fairchild PT-19A trainers flying last. Because they re-entered the square so quickly, the spectators were led to believe these were nine different Mustangs, with a total of twenty six planes appearing over Tiananmen square instead of the actual seventeen. This was mentioned in a government made propaganda newsreel. Of these nine Mustangs, at least one was a P-51K model.

After the parade, the Mustangs were once again deployed in a defensive state awaiting possible Nationalist intrusions in Beijing. By November 1949, the People’s Liberation Army Air Force was officially established and a total of twenty two airworthy Mustangs were in service, with nine more awaiting repair. This meant that thirty one Mustangs still survived, with eight written off. It is unknown what precisely happened to these Mustangs but the author speculates that they could have been cannibalized for parts, destroyed in training flights, disassembled to study the structure, or simply scrapped.

One of the only known photos of the two seat P-51D trainer. The canopy seemed to have been removed to make space. (js.voc.com.cn)

On July 26th 1950, the Beijing defense squadron was renamed the “Air Force 1st Independent Fighter Brigade” (空军独立第一歼击机大队). By then, the Soviet Union was supplying the Chinese with more modern equipment and by mid-August, the brigade’s Mustangs were replaced by Soviet Lavochkin La-9 fighters. Once replaced, all Mustangs scattered across the country were collected and given to Aviation School No.7 to train new pilots. With this, Aviation School No.7 modified thirteen Mustangs to be two-seat trainers. This was done perhaps to speed up the training process, and to prevent accidents by rookie pilots without guidance. There is currently one known photo of the two seat trainer.

By September 1953, most Mustangs were retired from training service due to cracks in the landing gear. However, eight of them remained in service with Aviation School No.7 to train Ilyushin IL-10 pilots how to taxi their planes. A few more examples were used as teaching tools to train pilots on identifying plane parts. It is unknown when precisely the Mustang was retired once and for all.

An illustration showing three P-51 Mustangs flying over Beijing on October 1st of 1949. (thepaper.cn)

Surviving PLAAF Mustangs

To this day, only two Mustangs formerly in PLAAF service survive in museums. The first one is a P-51K-10-NT “Red 3032” with the serial number 44-12458. This P-51K is on public display at the Chinese Aviation Museum (中国航空博物馆), sometimes also known as the Datangshan Aviation Museum located in Datangshan, Beijing. It remains in relatively pristine condition as it was in an indoors display and sheltered from the elements. Bomb hardpoints are visible under each of the wings which signifies that this Mustang perhaps once served as a fighter/bomber for the ROCAF.

P-51K-10-NT “Red 3032” on display. It is in rather good condition due to being stored indoors. (George Trussell)

The other surviving PLAAF Mustang is a P-51D-25-NA “Red 3” with the serial number 44-73920. This Mustang can be seen at the China People’s Revolution Military Museum (中国人民革命军事博物馆) in the Haidian District of Beijing. What is notable about this specific plane is that it was one of the nine Mustangs that flew over Beijing on October 1st of 1949 for the Founding of the People’s Republic of China parade. This Mustang was displayed outdoors exposed to nature for the majority of its life until the museum went under renovation when it was finally moved indoors. The Mustang has gone through minimal restoration, as it looks considerably cleaner than when it was displayed outdoors. This Mustang also had bomb hardpoints under its wings.

The P-51D-25-NA “Red 3” in its new indoor display after the museum renovation. It looks considerably cleaner than when it was displayed outdoors. (Wikimedia Commons)
The P-51D-25-NA “Red 3” in its old outdoors display, dust and slight rust can be seen on the machine. (Wikimedia Commons)

Variants Operated

A total of 39 North American P-51D Mustangs were operated by the Communist Chinese forces, and later the People’s Republic of China. Within these Mustangs, an unknown amount were P-51D and P-51K models.

  • P-51D – An unspecified amount of P-51D Mustangs of various block numbers were operated by the People’s Republic of China. A P-51D-25-NA is confirmed to have been in service as it flew over Beijing as part of the establishment of the People’s Republic of China parade and is now in the China People’s Revolution Military Museum (中国人民革命军事博物馆) in the Beijing.
  • P-51K – An unspecified amount of P-51K Mustangs of various block numbers were operated by the People’s Republic of China. A P-51K-10-NT is confirmed to have been in service as it is in the Chinese Aviation Museum (中国航空博物馆) in Beijing.
  • P-51 Trainer – A total of thirteen Mustangs were modified by Aviation School No.7 in 1951 to be two-seat trainers. The instructor sat in the rear while the student pilot was at the front. No surviving examples are preserved to this day.

Note

The author would like to extend his thanks to Mr. Hemmatyar for restoring some of the photos used in this article.

Gallery

P-51K-10-NT “Red 3032” displayed in the Chinese Aviation Museum in Datangshan, Beijing. Illustration by Brendan Matsuyama
P-51D-25-NA “Red 3” displayed in the China People’s Revolution Military Museum in the Haidian District of Beijing. Illustration by Brendan Matsuyama
A PLAAF P-51D/K with a blue rudder. The unit and serial number is unknown. Illustration by Brendan Matsuyama
A rare photograph of a mini P-51 Mustang model with PLAAF markings dated some time in the early 1950s. Two little boys accompany the cutout. This shows how impactful the Mustang was to the initial years of the People’s Republic of China. (eBay)
22 year old Lin Hu (林虎) with his P-51K before taking off to partake in the parade. (gogonews.cc)
A still frame showing three P-51 Mustangs flying over Beijing. (Establishment of the People’s Republic of China Parade)
A line of P-51 Mustangs awaiting inspection with their respective pilots standing at ease. (sohu.com)
A PLAAF Mustang taking off. Note the rocket rails. (Encyclopedia of Chinese Aircraft: Volume 2)
Mechanics and ground crew doing engine work on a Mustang. (Encyclopedia of Chinese Aircraft: Volume 2)
Four Mustangs line up on the Beijing Nanyuan Airfield awaiting to take off for the participation in the 1949 parade. Two Curtiss C-46 Commandos can also be seen in the background. (windsor8.com)

Sources

Gang, W., Ming, C. Y., & Wei, Z. (2009). 中国飞机全书 (Vol. 2). Beijing: 航空工业出版社., 八一战鹰大全(一)—— P-51“野马”战斗机. (n.d.). , Armstrong. (n.d.). 天马行空: 纪念 P-51 野马战斗机升空六十年., 肖邦振, & 李冰梅. (2010). 新中国成立前后 国民党空军飞行人员驾机起义探析. 军事史资料., Allen, K. (n.d.). PEOPLE’S LIBERATION ARMY AIR FORCE ORGANIZATION., (2016, December 19).开国大典——1949国庆大阅兵, Side Profile Views by Brendan Matsuyama

Plane side view

Consolidated Vultee XP-81

USA flag United States of America (1944)
Prototype Escort Fighter – 2 Built

The first XP-81 powered by the TG-100 engines (Convair)

The Consolidated Vultee XP-81 was a prototype mixed power fighter developed in late 1943 by the Consolidated Vultee Aircraft Corporation in order to meet an Army Air Force requirement calling for a high altitude escort fighter. Plagued by slow development and engine problems, the XP-81 would never see active service and development would be terminated in 1947. Despite this, the XP-81 still holds a distinct place in history as America’s first turboprop engine plane to fly and the world’s first plane to fly with a turboprop engine and a jet engine together.

History

With the formal introduction of the Boeing B-29 Superfortress on May 8th of 1943, it would be clear that a high altitude escort fighter would soon be needed to accompany the Superfortress on its bombing missions over the Pacific. In the summer of 1943, this need was realized and the United States Army Air Force (USAAF) issued a list of design requirements that consists of the following:

  1. 1,250 mile (2,012 km) operating radius
  2. Fuel for 20 minutes of combat plus reserve fuel supply for landing
  3. Cruising speed of 250 mph (402 km/h) at 25,000 ft (7,620 m)
  4. Maximum speed over 500 mph (804 km/h)
  5. Combat ceiling of 37,500 ft (11,430 m)
  6. Climb rate of 2500 fpm (feet per minute) / 762 mpm (meters per minute) while at 27000 ft (8230 m)
  7. Two engines*
  8. 12 ° angle of vision over the nose

* – The USAAF recommended that the designers use a two engine setup consisting of a propeller engine for long range flights while complemented by a jet engine for high speed combat situations.

Promotional illustration of the XP-81 showing a diagram of the XP-81. (Consolidated Vultee)

Interested in this proposal, the Consolidated Vultee Aircraft Corporation, later known as Convair, began work on an aircraft which would meet the specifications, appointing Charles R. Irving, who was a chief engineer of the Vultee Field Division and Frank W. Davis, the assistant engineer, who was also the chief test pilot, as the leaders of the design team. The project was known as the “Model 102” within Consolidated Vultee. In the early stages of development, the designers faced a dilemma of engine selection. The Pratt & Whitney R-2800 Double Wasp radial engine was considered, as was the General Electric TG-100 turboprop engine. After some evaluating and testing however, the TG-100 was selected as it was deemed to have superior performance for combat and cruising situations. As for the jet engine in the rear, a relatively straightforward choice to mount a General Electric J33-GE-5 (also known as I-40) jet engine was made. After a couple of months of development, Consolidated Vultee submitted a preliminary design proposal to the United States Army Air Force in September of 1943. Relatively interested in this design, the plane was given the greenlight for further development and received the designation “XP-81” by the Air Material Command.  

Detailed work on the XP-81 began in January 5th of 1944 and on January 18th, Consolidated Vultee was given the contract (no. W33-038-ac-1887) by the USAAF worth about $4.6 million to construct two flying XP-81 prototypes and one airframe for ground testing under the USAAF project name “MX-480”. Another contract followed on June 20th of 1944 worth $3,744,000 for the two flying examples, the airframe and the testing data. The contract was later modified to include 13 YP-81 under the project name “MX-796”. The construction of the first XP-81 prototype would begin on January 20th at the formerly independent Vultee aircraft factory in Downey, California but problems soon surfaced. Some time in April, the Air Material Command was notified that there would be a delay in the delivery of the TG-100 due to a couple of technical difficulties. As such, construction of the first prototype was delayed as the designers sought out an alternative engine to replace the TG-100 in June.

Consolidated Vultee flight test crew poses with the first XP-81 prototype. (XP-81)

The Packard V-1650-3 (some sources state V-1650-7), which was the American copy of the British Rolls-Royce Merlin engine, was selected to fill in the gap and the USAAF promptly provided Consolidated Vultee with such an engine taken from a North American P-51D Mustang. Within a week of receiving the engine, Consolidated Vultee engineers were able to install it after making considerable structural modifications to the first prototype’s airframe. A radiator similar to that of the Lockheed P-38J’s “beard” radiator would also be mounted on the XP-81, under the propeller spinner. Unfortunately for the designers however, the change of powerplant would add 950 lb (431 kg) to the plane while taking away 960 hp at takeoff and 1720 hp at top speed. With the relatively slow development, the first XP-81 prototype would finally be completed in January of 1945 bearing the serial number of “44-91000”.

Although the aforementioned issues with weight gain and horsepower loss were present, the Packard engine powered XP-81 was still deemed safe for flight tests, and as such, the first XP-81 prototype was prepared for test flights at Muroc Dry Lake in California and finally took to the skies on February 7th of 1945 with Frank W. Davis in the cockpit. Amazingly enough, 46 test flights were made with the Packard engine and it accumulated a total of 47.75 flight hours. In the testing phase it was noted that with the Packard engine installed, the XP-81 had poor directional stability at low speeds and the occasional splatter of oil on the windscreen by the propellers. Plans to replace the Packard engine were brought up on May 18th of 1945 when the TG-100 turboprop was finally available. The conversion was completed and the first prototype was returned back to Muroc for more tests on June 11th. Due to the new engine installation, extensive ground work had to be accomplished before flight tests were to continue. Throughout June 23rd to December 20th of 1945, numerous ground tests were conducted and a few problems surfaced. For one, the TG-100 was difficult to start and once it did, the pilot would have difficulty controlling the propeller. As this was an early turboprop engine,

reliability was low and the turbine wheels had to be replaced constantly, sometimes only after half an hour of use. The 10 inch (25 cm) oil cooler for the TG-100 was also deemed a problem, and it was thus increased to a 12 inch (30 cm) system instead. Perhaps the biggest problem however, was the throttle lag the XP-81 suffered. Frank W. Davis describes the problem by stating “The pilot had about a 10 second lag when he wanted to go and about 2 seconds lag when he wanted to stop, with both thrust and drag being powerful and non-adjustable when they did occur.” (Consolidated Vultee XP-81, by Steve Ginter). The ground personnel concluded in these ground tests that the current Aeroproduct A542 propeller and drive shafts were incompatible with the TG-100, and that new propellers should be developed. An emergency engine feathering system was also recommended.

The first flight of the XP-81 with the TG-100 engine occured on December 21st of 1945. This was the 47th test flight the first XP-81 underwent. Performance was rather satisfactory, and the flight concluded after a mere 5 minutes. Excessive oil consumption was noted however. Test flights with the TG-100 proved disappointing as the turboprop did not perform as it was advertised, delivering less horsepower than was expected. Out of the estimated 2,300 hp the TG-100 was suppose to achieve, only 1,400 hp was achieved. The I-40 engine was no help either, as it developed nearly 250 lb (113 kg) less thrust than advertised as well. The estimated performance of 478 mph (769 kmh) at sea level was not achieved with only a mere 400 mph (643 kmh) achieved. Due to these factors, the performance achieved was similar to that of the Packard engine installation. Despite these problems, the XP-81 still did well in some aspects. The relatively decent handling and decent climb rate was complemented, as was the light controls. The second prototype (serial no. 44-91001) was produced some time before November of 1946, and was ready for flights by February of 1947. It featured a longer ventral fin than that of the XP-81 and had a four blade Hamilton Hydromatic propeller replacing the Aeroproducts propeller used on the first prototype. Unfortunately, it is unknown what date the second prototype made its maiden flight, but it is speculated that it first flew some time in February of 1947.

In total, 116 flights were made by both of the XP-81 prototypes, 22 of which were done by the second XP-81 prototype. More tests were planned, as on January 14th of 1947, Consolidated Vultee called for the following areas to be studied and tested:

  1. Firearms testing of the Browning AN/M2 and the Hispano T31. Bombs and rockets tests will also be included.
  2. Anti-icing equipment efficiency.
  3. Control characteristics and lateral stability.
  4. Cabin pressurization experiments.
  5. Power plant operations.
The first XP-81 prototype taxiing on the Muroc airstip in preparation of a flight on January 22nd of 1946 (SDAM)

However due to the previously mentioned issues of the XP-81 underperforming, the USAAF gradually lost interest in the XP-81 program. Consolidated Vultee was well aware of this, and they had been trying since December of 1946 to improve their design. A proposal was made in December 31st to the Air Material Command to fix the underperforming prototypes. This proposal suggested that an improved TG-110 (the ones that would have been used on the YP-81) should replace the TG-100 and a J33-19 jet engine should replace the J33-GE-5. The Air Material Command however was not impressed by the proposal due to the amount of redesigning and time needed and in early 1947, their engineering department ceased work on the TG-100 turboprop engine. Things would look even more grim for the XP-81 when on January 27th of 1947, the contract for the 13 YP-81 pre-

The first XP-81 prototype flies over the Mojave Desert. (Convair)

production fighters were cancelled. Finally on May 9th, the XP-81 program reached its end when the government decided to cancel the contract on its development. The two prototypes were then taken in by the USAAF on June 24th and 25th. Finalization of the cancellation was conducted on June 23rd of 1948 after the USAAF was reorganized into the United States Air Force (USAF) when Consolidated Vultee was reimbursed with $4,578,231 for their work on the program.

Though development stopped for the XP-81 program, the two prototype’s story did not end there. At the time when the USAAF took in the prototypes, the engine and propeller development branches of the Air Material Command was in the middle of developing more advanced propeller control techniques and a suitable machine was needed to perform tests on as wind tunnels and models were not available. The USAAF promptly provided the two XP-81s which were redesignated as “ZXF-81” for this new role. The two planes were then stored in Edwards AFB (previously known as Muroc AAF) for future use. Unfortunately, they were never used and on April 29th of 1949, all useful parts and gadgets were stripped from the two planes by order of the USAF. The two empty airframes were then dragged onto the photography & bombing range of the Edwards AFB.

Despite the XP-81s now sitting in the desert, Consolidated Vultee was still not willing to yield completely. The company tried proposing reviving the XP-81 program using different power plants and repurposing the role. The proposal called for the use of the British Armstrong-Siddeley Double Mamba turboprop producing 4,000 hp and a Rolls-Royce R.B 41 jet engine producing 6,250 lbf (2,835 kgf) of thrust replacing the original engines. The idea behind this was to create a ground attack aircraft which could be exported to other countries. However, this idea was understandably met with skepticism by the Air Force, but an investigation to see the feasibility of this proposal was made. On September 14th of 1950, a report was finalized stating that at least ⅔ of the airframe would need to be modified in order to mount the new engines.  New drop tanks, rocket rails, hardpoints and various other parts would also need to be redesigned. Another investigation was done on this proposal by comparing the hypothetical performance to the all-turboprop Douglas A2D Skyshark, a ground attacker aircraft in service with the USAF. It was determined that the Skyshark would outperform the XP-81 with British engines in all aspects, so there was no point in developing an inferior aircraft. Another factor that was noted was the excessive amount of maintenance, training and logistics needed to service the ground attacker. With all these factors in mind, the proposal was discarded by the USAF and Consolidated Vultee finally gave up on the XP-81.

Frank Davis sits in the cockpit of the XP-81. (Convair)

The two XP-81 airframes would remain in the desert exposed to the elements for decades until August of 1994 when Air Force Flight Test Center Museum curator Doug Nelson retrieved them. They were in derelict condition, with the second XP-81 prototype being more damaged than the first. As of 2018, the two airframes remain in the National Museum of the United States Air Force in Dayton, Ohio awaiting future restoration. Although never seeing service, the XP-81 still holds a distinct spot in history as America’s first turboprop engine powered plane to fly and the world’s first plane to fly with a turboprop engine and a jet engine together.

The first XP-81 prototype at the Edwards AFB shortly before recovery. (AFFTCHO)

Design

Airframe:
The XP-81’s semi-monocoque fuselage was constructed using age hardened 24-SRT aluminum alloy, followed by the exterior surfaces being flush riveted. The entire fuselage is made from metal. The wing design was a NACA laminar flow type, made from aluminum-alloy. The design allowed for a stressed-skin wing which was flush riveted as well, with the rivet heads being milled. Due to the relatively heavy materials used in the wings, the surface was relatively smooth thus allowing for good aerodynamics. The majority of the heavy plating was mounted in the frontal 34.5% of the wings, and thus allowed a decent mount for aerial weapons and permitted ordinance to be mounted. There were spoilers present on each wing which automatically operated in accordance to the ailerons. Another interesting feature was a thermal anti-ice system derived from the hot hair emitted from the TG-100 turboprop and the exhaust. Within the fuselage two fuel tanks were installed directly behind the cockpit, making for a total 811 gallons (3670 L) of fuel. The fuselage also housed the XP-81’s tricycle landing gear which was electrically operated. The main gear was fitted with disc brakes, also doubling as a parking brake.

The first XP-81 prototype’s Packard engine installation being finalized at the Vultee plant. (Convair)

The canopy on the cockpit was based off of the British bubble design, which allowed for a relatively clean 360° view. This type of canopy was used on many planes in service with the United States and Britain. The canopy would be controlled by the pilot via a hand crank on the left hand side of the cockpit. For fatal combat situations, an emergency canopy jettison system was provided allowing for the pilot to bail out quickly. The pilot’s seat was an ordinary World War II styled seat, but this was eventually replaced with an ejection seat modelled after the one used on the Convair XP-54. As the XP-81 was a long range fighter, an automatic piloting system was also installed. The cockpit would also be pressurized using the air from the TG-100 engine. For pilot comfort, a temperature system was installed allowing for optimal temperatures in all climate and altitudes.

For communication, the XP-81 was fitted with a VHF (Very High Frequency) SCR 522-A radio set. The cockpit also had room for a BC-1206 beacon receiver and an SCR 695 identification friendly-or-foe system, but these were never installed. The pilot would operate the SCR 522-A radio from the right side of the cockpit, where the radio controls were based.

It is also interesting to note that the second YP-81 prototype had a longer ventral fin than the first prototype.

Powerplant:

The Packard-powered XP-81 prototype idle on the Muroc airstrip. (Convair)

The XP-81’s design called for a General Electric TG-100 (also known as XTG-31-GE-1) turboprop and General Electric/Allison J33-GE-5 (I-40) jet engine as its power plants. The first prototype had a four blade Aeroproducts A542 brand propeller driving the TG-100 while the second prototype had a Hamilton Standard Hydromatic 4260 propeller instead. The TG-100 had a capacity for 8 gallons (30 L) of oil while the I-40 had 3.5 gallons (13 L). In terms of fuel, 811 gallons (3,670 L) was available in the XP-81’s two standard fuel tanks in the fuselage, but could go up to 1,511 gallons (5,720 L) with the installation of drop tanks.

The TG-100 Turbo Prop Engine

Armament:
The standard armament envisioned for the production P-81 would consist of either six 12.7x99mm Browning AN/M2 machine guns with 400 rounds each or six 20x110mm Hispano T31 cannons with 200 rounds each. The loadout of these guns would be in groups of three in each wing. For ordinance, a single hard point was mounted under each wing, allowing the plane to carry two bombs size ranging from 100 lb (45 kg) to 1,600 lb (725 kg), allowing for a maximum of 3,200 lb (1,451 kg). Chemical tanks, drop tanks, depth charges could also be equipped. Alternatively, 14 High velocity Aircraft Rockets (HVAR) could be carried.

Variants

  • XP-81 – Prototype fighter variant powered by a TG-100 turboprop and I-40 jet engine. Two examples were produced and extensively tested up until the cancellation of the project. Both prototypes were redesignated as “ZXF-81” in 1948 and stored in Edwards AFB. They would be stripped of useful parts and towed to the photography/bombing range near Edwards AFB and left there in derelict condition until August of 1994 when they were retrieved by Doug Nelson. The two airframes still survive to this day and are currently awaiting restoration at the National Museum of the United States Air Force in Dayton, Ohio.
  • YP-81 – Planned batch of 13 pre-production fighter variant powered by a lighter but more powerful TG-110 turboprop engine and an uprated General Electric J33-GE-5 turbojet engine. These planes would have been armed with either the Browning AN/M2 machine guns or the Hispano T-31 cannons. It would have differed from the XP-81 by having the wings moved back 10 inches (2.54 cm). No YP-81s were produced.
  • ZXF-81 – Post development termination designation for the two XP-81 prototypes. This designation signified that the prototypes were now flying test beds. However, no use of the prototypes after its termination was noted.
  • XP-81 (British Engines) – Unofficial variant proposed by Consolidated Vultee some time in 1949/1950 calling for the revival of the XP-81 project using British Armstrong-Siddeley Double Mamba turboprop producing 4,000 hp and a Rolls-Royce R.B 41 jet engine producing 6,250 lb (2,835 kg) of thrust replacing original engines. This new variant would be used as a ground attacker that would be solely used for export. This proposal never saw any development and was thus discarded.

Operators

  • United States of America – The XP-81 was intended to be used by the USAAF, but development carried over to the USAF. The project was eventually cancelled.
Consolidated Vultee Aircraft Corporation XP-81
(Taken from “Consolidated Vultee XP-81 by Steve Ginter”)
Wingspan 50 ft 6 in / 15.39 m
Length 44 ft 8 in / 13.61 m
Height 13 ft 10 in / 4.21 m
Wing Area 425 ft² / 39.48 m²
Wing Loading 45.9 ft² /  4.26 m²
Tire Loading 80 in² / 516.12 cm²
Wings Sweep Back
Wing Dihedral
Root Cord 13-1
Engines 1x General Electric XTG-31-GE-1 (TG-100) turboprop
1x General Electric / Allison J33-GE-5 (I-40) jet
Oil Capacity TG-100: 8 gallons / 30 L
I-40: 3.5 gallons / 13 L
Empty Weight 12,755 lb / 3,887 kg
Normal Weight 19,500 lb / 8,845 kg
(Maximum internal fuel with reduced armaments)
Maximum Combat Weight 24,650 lb / 11,181 kg
Fuel Capacity 811 gallons / 3,070 L – Internal Fuel Tanks
1511 gallons / 5,720 L – Internal Fuel Tanks + Drop Tanks
350 gallons / 1,325 L – Individual Drop Tank
Center of Gravity Max Forward – 17%
Max Aft – 27%
Rate of Climb 0 to 5,000 ft / 0 to 1,524 m – 5,200 fpm / 39.31 mps
Time of Climb 30,000 ft / 9,144 m in 9.6 minutes
Speed 299 mph / 481 kmh at Sea Level
253 mph / 407 kmh at 15,000 ft / 4,572 m
224 mph / 360 kmh at 30,000 ft / 9,144 m
Maximum Speed 546 mph / 877 kmh
Diving tests were never finalized due to propeller and engine problems. Flight #90 on September 4th of 1946 achieved the highest speed as mentioned above.
Range Conditions under maximum combat weight

Ferry Range – 2,393 mi / 3,851 km
Speed at 247 mph / 397 kmh – 2,002 mi / 3,222 km
Speed at 274 mph / 441 kmh – 1,622 mi / 2,610 km

Service Ceiling 47,000 ft / 14,000 m
Crew 1x Pilot
Radio Equipment SCR 522-A VHF Radio
Armament 6x 12.7x99mm Browning AN/M2 (400 rpg, 2,400 total)
or
6x 20x119mm Hispano T31 (200 rpg, 1,200 total)
Never Fitted on Prototypes, Intended Armament
Gunsight 1x K-14 Gyro Gunsight
Ordinance 2x hardpoints capable of carrying 3,200 lb / 1,452 kg of either bombs, depth charges, chemical tanks or drop tanks
or
14x 5 inch / 12.7 cm High Velocity Aircraft Rockets (HVAR)

Gallery

Plane side view
Sideart of the XP-81 by Escodrion

 

XP-81 parked on a ramp.
Side view of the XP-81 on the ground.
Rear view of the XP-81 on the ground. Note the position of the exhaust pipe relative to the two fuselage mounted air intakes.
XP-81 in flight.
Instrument panel of the XP-81. (USAF)
Controls of the XP-81. (USAF)
The second XP-81 prototype at the Edwards AFB shortly before recovery. (AFFTCHO)
The second XP-81 prototype at the Edwards AFB shortly before recovery. The helicopter shadow visible is possibly an H-21 ‘Flying Banana’ (AFFTCHO)
The second XP-81 prototype preparing to be transported. (AFFTCHO)
The second XP-81 prototype preparing to be transported. (AFFTCHO)

Sources:
Ginter, S. (2006). Consolidated Vultee XP-81. Simi Valley: Steve Ginter.Jenkins, D. R., & Landis, T. R. (2008). Experimental and Prototype: U.S. Air Force Jet Fighters. North Branch: Specialty Press.Wegg, J. (1990). General Dynamics Aircraft: And their Predecessors. London: Putnam Aeronautical Books.Baugher, J. (1991). Convair XP-81. National Museum of the US Air Force (n.d.). Convair XP-81. Images: Side Profile Views by Escodrion – https://escodrion.deviantart.com

 

Gasuden Kōken-ki

 Empire of Japan (1937)
Long Range Research Aircraft- 1 Built

The Gasuden Kōken-ki was Japan’s attempt at building a world record setting plane for the longest distance covered in a non-stop flight. First conceived in 1931 to surpass John Polando and Russell Boardman’s flight, the Kōken-ki would have a slow development finally completed and ready for flight on August 8th of 1937. Though 6 years late and many other world records for distance had been set, the Kōken-ki still managed to prove its worth on May 13th of 1938 where it made a non-stop flight in a closed-circuit course in Japan covering 7239.58 mi (11651.011 km), a record that Japan would hold until 1939.

History

In the 1920s and 1930s, many countries were competing against each other for setting aviation-related world records, be it endurance, speed or distance. The goal of establishing a long distance world record was one of the most popular ambitions a country could have. The 1931 world record was established by John Polando and Russell Boardman, flying a Bellanca J-300 Special nicknamed “Cape Cod” from Floyd Bennett Field in New York to Istanbul, Turkey. The distance covered by these two men spanned 5011 miles (8066 km). The Empire of Japan was by no means idle in the conquest for setting the world record. The Kōkū Kenkyūjo (Aeronautical Research Institute) began to formulate a design proposal in the latter half of 1931 for a plane that would be able to beat Polando and Boardman’s record flight. The Kōkū Kenkyūjo was on good terms with the Tokyo Imperial University, and convinced them to put their design forward to the Monbushō (Ministry of Education). The design proposal moved rapidly through the approval process and eventually made its way to the Kokkai (Diet). Relatively confident in the design, the Kokkai approved the Kōkū Kenkyūjo’s design and provided them with a monetary grant.

A factory worker fitting parts on the tail section of the Kōken-ki. (Arawasi)

With adequate funding and support of the government, the Kōkū Kenkyūjo began to formally investigate the matter of designing the plane. The plane was now named the Kōken-ki (航研機). The man responsible for overseeing the project was Dr. Koroku Wada, with professor Keikichi Tanaka assisting him. Many members of the design staff were from the engineering department of the Tokyo Imperial University. Various committees were also formed for the purpose of designing the Kōken-ki. It would take two years until the basic design was completed. By the time the design was finished in August of 1934 however, another world record had been set by French aviators by the names of Maurice Rossi and Paul Codos. The French aviators were able to surpass the previous record set by Polando and Boardman by 645 miles / 1038 km by flying their Blériot 110 monoplane from New York to Rayak, Syria on August 5th of 1933. The Japanese were confident that they would soon be able to best this record, as they’d designed the Kōken-ki to endure 8078 miles (13000 km) of flight.

The next step for the Kōken-ki was construction, but this process would be slow as the advanced design of the Kōken-ki had to be completed first. Various components and tooling would be manufactured the following year. The Tokyo Gas and Electric Industry (known as Gasuden) was selected to be the manufacturer of the airframe, while Kawasaki Kokuki KK. was selected to manufacture the powerplant, which would be a licensed Japanese made version of the German BMW VII engine. Once the advanced design was completed, construction began. Due to the fact that Gasuden was relatively inexperienced with metal fabrication, the construction of the Kōken-kid would be delayed. The major components of the Kōken-ki were finally completed on March 31st of 1937, and were promptly moved to a hanger owned by the Teikoku Kaibo Gikai (Imperial Maritime Defence Volunteer Association) at Haneda Airport where it was to be assembled. On August 8th of 1937, the assembly was completed and the Kōken-ki was ready for its maiden flight.

Test pilots for the plane were carefully selected as testing the potential record setter was a matter of great importance to the Japanese. A decision was finally made with Major Yuzo Fujita as the pilot, Master Sergeant Fukujiro takahashi as the co-pilot and Flight Engineer 

From left to right is Major Fujita Yuzo, Flight Engineer Sekine Chiaichi and Master Sergeant. (Arawasi)

Chikakichi Sekine as the flight engineer. All of these men belonged to the Imperial Japanese Army’s Rikugun Kokugijutsu Kenkyū (Air Technical Research Institute) and had been involved with the design of the Kōken-ki since the start. The long awaited maiden flight finally took place on May 25th of 1937. The test flight went well with no problems to report, so plans for the Kōken-ki’s official record setting flight was set in motion. More test flights had to be completed, so the three men continued fly the Kōken-ki. Meanwhile, the Soviet Union’s own Tupolev ANT-25 made its record flight on June 18th of 1937 where it flew from Moscow over the North Pole and landed in Vancouver, Washington. This flight took the Russian pilots 63 hours and covered 5670 mi (9130 km). The Japanese however, were not concerned as the Kōken-ki’s range was surely able to surpass this. 

The first attempt for setting the world record was conducted by Japan on November 13th of 1937. Unfortunately for the Japanese, a landing gear failure surfaced and the Kōken-ki had to be grounded for months until May 10th of 1938. This second attempt was also met with a problem, as the autopilot system malfunctioned. This problem was far simpler to remedy than the landing gear, and was rapidly repaired. On May 13th at 4:55 AM, the Kōken-ki successfully took off from Kisarazu Naval Air Base near Tokyo Bay to break the world record. To verify the authenticity of the flight, Imperial Japanese Navy Lieutenant-Commander Tomokazu Kajjiki was to monitor the

A poster advertising Nisshin’s salad oil, with the Kōken-ki displayed in the background. (Arawasi)

flight as he was the Fédération Aéronautique Internationale’s (World Air Sports Federation) representative for Japan. The flight plan of the Kōken-ki was to follow a square shaped course that would lead to Choshi from Kisarazu, then to Ohta and back to Kisarazu. Many minor problems occurred during the flight, such as a tear in the water cooler. The Kōken-ki flew the square course for 29 laps nonstop, and finally completed its task of setting the world record, amassing a total distance of 7239.58 mi (11651.011 km). The Kōken-ki landed back at Kisarazu at 7:21 PM of May 15th after almost 63 hours. Upon landing, the flight of the Kōken-ki was officially approved as a world record by the FAI. It is noteworthy that the Kōken-ki was reported to still have about 132 US gallons (500 L) of fuel left, meaning that it could have potentially flown another 745 mi (1200 km). Nonetheless, it was an achievement which made the nation proud. The Kōken-ki was then featured on many advertisement posters in Japan.

The Japanese were able to hold the world record for about 15 months before being beaten by the Italians in August of 1939. The Italians flew a Savoia-Marchetti SM.82 and covered a distance of 8038 mi / 12936 km over a closed-circuit course. Nonetheless, the flight by the Kōken-ki was still an incredible feat for the Japanese, as it was the first and only Japanese plane to obtain a FAI world record at the time. After the record setting flight, the Kōken-ki would mostly remain in the Kaibo Gikai hangar where it was first assembled. Occasionally, the Kōkū Kenkyūjo would and perform test flights for various purposes. After the Kōken-ki was past its prime, the Japanese wanted to see if they could further improve their long distance flight. In the eyes of professor Hidemasa Kimura, the Kōken-ki was only useful for challenging the world record for distance, but not for anything else. As such, Kimura decided to design a plane which would be capable of flying from Tokyo to New York, a route spanning 6737 mi (10842 km). The work of this would result in the Tachikawa Ki-77, or A-26.

From left to right, Chikaichi, Takahashi and Fujita receiving the Japanese “Yokosho” medal for their feat. (Arawasi)

The Kōken-ki flew for the last time on June 14th of 1939 as a commemoration for Major Fujita, the pilot of the record flight who was killed in combat in China.  After Major Fujita’s funeral flight, the Kōken-ki was stored in the Haneda Airport and remained there for the entire duration of World War II in relatively pristine condition. However after Japan surrendered, American occupational forces began to arrive and began a long process of demilitarizing Japan. Upon reaching Haneda airport, all of the Japanese planes there ,military or not, were targeted for destruction. The Kōken-ki and every other Japanese plane present at the airport was towed to the field and burnt in a mass pile, thus bringing an ungraceful end to the Kōken-ki.

Design

A closeup on the Kawasaki-built BMW VIII engine.

The Gasuden Kōken-ki had an all-metal semi-monocoque fuselage which housed a Kawasaki-built German BMW VIII engine driven by a Sumitomo SW-4 two-bladed metal-shrouded wooden propeller. The wings of the Kōken-ki were carefully designed with the intent of allowing it to operate in thinner air. The cantilever wings were constructed using a Kōken-ki Model 4 aerofoil shape, with about 17.5% thickness. The wingtips however, had a different material which was Kōken-ki Model 11 alloy. This aerofoil only had 4% thickness. The resulting wings had an aspect ratio of 8.7. As the plane was designed with range and endurance in mind. 14 fuel tanks were installed in the wings allowing for 1538 US gallons (5822 L) of fuel. A system was also installed which would allow the fuel to even out in all the tanks in order to maintain center of gravity. The landing gear of the Kōken-ki was retractable in order to reduce drag and once retracted, fairings would cover the landing gear wells. The cockpit was set on the left side of the plane, giving it an asymmetrical design. The Kōken-ki’s windshield could be extended and folded in order to reduce drag. Only when taking off and landing would it be extended. This design was a hindrance for the pilots as they reported poor visibility and control. The Kōken-ki was completely metal, with the exception of fabric covers which were fitted over the control surfaces and wings.

Operators

  • Empire of Japan – The Gasuden Kōken-ki was operated solely by Japanese pilots for all the flights it flew.

Gasuden Kōken-ki

Wingspan 91 ft 7 in / 27.9 m
Length 49 ft 5 in / 15.1 m
Height 11 ft 9 in / 3.6 m
Wing Area 939.7 ft² / 87.3 m²
Wing Loading 21.6 lb/ft² / 105.9 kg/m²
Power Loading 25.3 lb/hp / 11.5kg/hp
Engine 1x Kawasaki-built BMW VIII 12-cylinder water cooled V-engine (715 hp)
Propeller 1x Sumitomo SW-4 two-bladed metal-shrouded wooden propeller
13 ft 1.5 in / 400 cm
Fuel Load 1538 US gallons / 5822 L
Empty Weight 9314 lb / 4225 kg
Loaded Weight 20317 lb / 9216 kg
Maximum Speed 155 mph / 250 kmh at Sea Level
152 mph / 244 kmh at 6562 ft / 2000 m
Cruising Speed 131 mph / 211 kmh at 6562 ft / 2000 m
Range 8078 mi / 13000 km
Maximum Service Ceiling 11187 ft / 3410 m
Crew 1x Pilot
1x Co-Pilot
1x Flight Engineer

Gallery

Kōken-ki sideart by Ed Jackson
The Kōken-ki being prepped for flight by ground crew and an armed guard. (Arawasi)
The Kōken-ki taking off. (Arawasi)
Underside view of the Koken with its gear retracted.
The Kōken-ki in the factory during construction. Note the exposed engine. (Arawasi)
Engineers working on the Kōken-ki. (Arawasi)
A poster advertising Nitto’s black tea. The Kōken-ki is featured in the background. (Arawasi)
A 1939 postage stamp commemorating the Kōken-ki’s record flight. (Arawasi)
A replica of the Koken-ki on display in a museum in Japan

A Series of Youtube Videos on the World Record Attempt:

Sources

Takenaka, K. (2007). Koken Long-range Research-plane.Swopes, B. (2017). 13–15 May 1938.Tupolev ANT-25 Soviet Long Range Record Setter. (n.d.). Fiddler’s Green.Mikesh, R. C., & Abe, S. (1990). Japanese aircraft, 1910-1941. Ann Arbor, MI: Naval Institute.Dyer, E. M. (2015). Japanese Secret Projects: Experimental Aircraft of the IJA and IJN 1922-1945. Ian Allan Publishing. Images: Side Profile Views by Ed Jackson – Artbyedo.com, Other images from http://arawasi-wildeagles.blogspot.com/

 

Mitsubishi G7M “Taizan”

 Empire of Japan (1941)
Strategic Bomber- 1 Scale Mockup Built

The Mitsubishi G7M “Taizan” (泰山/Great Mountain) was a planned long range strategic bomber for Imperial Japan’s Army Air Service. Developed out of the need for a bomber capable of striking the continental United States, the Taizan would face a series of developmental problems, ultimately leading to the cancellation of the project.

History

Prior to the start of World War II, Japan had foreseen that in a potential future conflict with the United States, it would require a long range bomber capable of striking the US mainland. In order to fulfill this requirement, a review was conducted in 1941 of all the Imperial Japanese Navy’s bomber aircraft in service. It was revealed that the entirety of the Japanese bomber arsenal was incapable of striking targets in the United States from the Japanese airfields. The Mitsubishi G4M “Betty” was one of Japan’s newest aircraft being pushed into service. Despite its superior range of 3,749 mi (6,043 km) compared to previous IJN bombers, it still was not sufficient enough to strike the US mainland or targets deep in the Soviet Union. As a result of this, the Naval Kōkū Hombu (Aviation Bureau) issued the 16-shi specification in 1941 for a long range bomber. The 16-shi specification would call for a bomber capable of flying at least 361 mph (580 km/h) with a maximum range of 4,598 mi (7,340 km).

Interested in this specification, Mitsubishi’s staff began work on a design that would meet the criteria set by the Kōkū Hombu. Mitsubishi engineer Kiro Honjo (the designer of the G3M and G4M) proposed a four engine design, but this was promptly rejected by the Kōkū Hombu. As a result, another Mitsubishi engineer by the name of Kijiro Takahashi submitted his own design. Upon inspection by the Kōkū Hombu, Honjo’s design was approved and given the green light to proceed. Within Mitsubishi, the 16-shi design was known as the “M-60”. Takahashi’s design was to be powered by two “Nu” engines. The Nu was a 24 cylinder liquid cooled engine which was able to provide 2,200 hp at 16,404 ft (5,000 m) but, due to the start of Operation Barbarossa, Germany was unable to export machinery and tools needed to manufacture the Nu engine. Unfortunately for Takahashi, this turn of events would prevent his design from being completed. As a result of this, Takahashi fell out with the Kōkū Hombu and Kiro Honjo would take over the M-60 project. This time, Honjo followed the Kōkū Hombu’s suggestion and used two engines instead of his idea of four. Under Honjo’s lead, the Taizan’s power plant was changed to two 18 cylinder Mitsubishi Ha-42-11 engines capable of generating 2,000 hp each. It was also seen that Honjo’s design was less aerodynamic than Takahashi’s due to the weaker engines and heavier armament.

On October 31st of 1942, an evaluation was conducted on the work done so far, and a performance estimation gave the Taizan a range of 3,454 mi (5,559 km) and a speed of 332 mph (518 km/h) at 16,404 mi (5,000 m). Falling short of the original 16-shi specification, Mitsubishi scrambled to make adjustments but further revised estimates stated that the design didn’t see any improvements, and actually saw some deterioration. By the time the Taizan’s design was completed in late 1942 and ready for construction of a wooden mockup, a new 17-shi specification was released calling for a new bomber design. Kawanishi took up the design and created the K-100 bomber project. Seeing promise and a better alternative to the Taizan, the Kōkū Hombu ordered all work on the Taizan to be halted until the K-100 could be completed and evaluated. Kawanishi completed initial work on the K-100 and a comparison was made between K-100 and Taizan in the summer of 1943. The Taizan’s range differed significantly from the proposed normal range from 2,302 mi (3,705 km) to 1,726 mi (2,778 km). Due to the significant range reduction, the Kōkū Hombu stopped supporting the Taizan. With no more interest and reason to develop the Taizan, Mitsubishi would finally shelve the project and stop all work on it.

Design

From an exterior aesthetic point of view, the Taizan bears a striking resemblance to the German Heinkel He 177. The nose of the Taizan was rounded and glazed over, a new design not in use by any Japanese bombers at the time. The wings of the Taizan were mounted mid fuselage, and were to be constructed out of metal. Fabrics, however, were to be used for the cover of the Taizan’s ailerons and rudder.

Ordinance wise, the Taizan was to carry a maximum bomb load of 1,764 lbs (800 kg). The defensive armament underwent several changes. Takahashi’s Taizan design was to be armed with two 20mm Type 99 Mk.2 cannons and two 7.7mm Type 97 machine guns. Honjo’s initial design would carry two 20mm Type 99 Mk.2 cannons, two 13mm Type 2 machine guns and two 7.92mm Type 1 machine guns. Later on, the armament finalized at two 20mm Type 99 Mk.2 cannons and six 13mm Type 2 machine guns. There would have been one Type 99 Mk.2 in the nose and one in the tail. There would have been two Type 2 machine guns in the forward upper fuselage turret, two in the rear fuselage turret and two in ventral position, firing rearwards.

Operators

  • Empire of Japan – The Taizan would have been operated by the Imperial Japanese Navy Air Service.

 

Mitsubishi G7M1 “Taizan” *

*Estimated performance of Mitsubishi’s G7M1 proposal

Wingspan 82 ft / 25 m
Length 65 ft 6 in / 20 m
Height 20 ft / 6.09 m
Engine 2x Mitsubishi Ha-42-11 (2,000 hp)
Power Loading 8.8 lbs/hp / 3.99 kg/hp
Empty Weight 23,368 lbs / 10,600 kg
Usual Weight 35,273 lbs / 16,000 kg
Fuel Capacity 4,497 L / 1,188 US Gallon
Climb Rate 32,808 ft / 10,000 m in 10 minutes
Maximum Speed 344 mph / 544 kmh @ 26246 ft / 5,000 m
Typical Range 1,739 mi / 2,799 km
Maximum Range 4,598 mi / 7,400 km
Crew 7
Defensive Armament 6x 13x64mm Type 2 machine guns

2x 20×101mm Type 99 Mk.2 cannons

Ordnance / Bomb Load 1,764 lb / 800 kg – Maximum

Gallery

 

Artist’s conception of the operational G7M Taizan

Sources

Dyer, E. M. (2013). Japanese secret projects: experimental aircraft of the IJA and IJN 1939-1945. Burgess Hill: Classic.Aircrafts of Imperial Japanese Navy. (n.d.). Retrieved February 06, 2018, from http://zenibo-no-milimania.world.coocan.jp/epljn.htmlImages: Side Profile Views by Ed Jackson – Artbyedo.com

 

Blohm & Voss BV 144

nazi flag Nazi Germany (1940)
Prototype Passenger/Transport Plane – 2 Built

Born out of Deutsche Lufthansa’ vision of an advanced airliner to replace the aging Ju 52 after the war, the BV 144 is arguably one of the rather unique looking passenger airliner planes of the 20th century. Although designed by Blohm & Voss in 1940, the first flying prototype wouldn’t take to the air until 1944, when the development of the BV 144 was no longer relevant to its original purpose and the Germans were in full retreat.

History

With rapid advances in Western Europe throughout 1940, Nazi Germany was confident that the war would be over soon. With such conditions in mind, it was very reasonable for Deutsche Lufthansa to start drafting up plans for their commercial airliner services after the war. Looking for a new aircraft to replace their aging Junkers Ju 52 transport, Deutsche Lufthansa turned to Blohm & Voss in 1940 in hopes of an advanced airliner. The design was finalized in early 1941, and was ready to be constructed. With France recently defeated, the Germans decided to take advantage of the French industry and ordered two prototypes to be constructed at the Louis-Breguet Aircraft Company factory in Anglet, in the Nouvelle-Aquitaine province of France.

BV.144 in its assembly stage. Note the large forward lamp assembly in the nose.

Although construction started in 1941, the first prototype would not be completed until sometime between July and August of 1944. By this point, the war situation for Germany had became alarmingly worse and the BV 144 was no longer seen as important. Another factor which may have been the cause of the slow construction was the deliberate low effort put into construction by the French workers, as they didn’t wish to help Germany progress. Finally, in August of 1944, the first prototype of the BV 144 would take to the sky. Unfortunately for the Germans however, the Allied forces were moving rapidly through France after Operation Overlord. This meant the Germans were forced to abandon the BV 144 prototype due to their retreat.

After the Liberation of France, the Louis-Breguet Aircraft Company factory fell back into French hands, as well as the completed BV 144 prototype and the second unfinished prototype. Both were transported to Toulouse via road and received French registration numbers. Intrigued by the relatively advanced design, the French would continue testing the BV 144 post war. The second unfinished prototype was also completed by the French post war, but it is unknown whether or not this prototype flew before the termination of the BV 144 project once and for all. Both prototypes were scrapped.

Design

BV.144 seen with French markings

The BV 144 was an all metal monoplane with a distinguishing high wing design and a tricycle landing gear configuration. It would have been powered by two BMW 801 MA 18-cylinder engines generating 1600 horsepower. The wings were located at the shoulder position of the fuselage, giving the engines a large ground clearance. Combined with the relatively short tricycle landing gear, the design would be advantageous to passengers as the fuselage would be close to the ground, allowing much easier boarding and disembarking.

The cockpit consisted of a pilot and a co-pilot in a stepped cabin, as well as a compartment for a radio operator. Following this compartment, there would have been a cargo storage, a passenger compartment, a toilet and another cargo storage.  At the cost of some cargo and a less spacious passenger compartment, the passenger count could have been raised to 23 from the original 18.

BV.144-1
Forward view of the BV.144

Foreseeing problems with takeoff and landing, Blohm & Voss designed the plane with variable incidence wings, which meant there were electric-mechanical systems fitted into the BV 144 that allowed the wing to rotate 9 degrees around its tubular main spar within the plane. Such a system was previously tested in 1940 on the Blohm & Voss Ha 140V-3 hydroplane with success. This interesting system would have allowed the pilot to change the sweep angle of the wings during low speed landing and takeoffs without having to shift altitudes. It would also allow the pilot to have a slightly better view during landing. Along with that, long slotted flaps were also provided to aid in landing.

Side view of the BV.144 with French markings

Another interesting feature of the BV 144 was the aforementioned tubular main spar, which was patented by Richard Vogt, the chief designer for Blohm & Voss. Although quite light in terms of weight, the spar would have been able to provide excellent load carrying characteristics. On top of this, as a surprising feature, the spar could also have been used to carry extra fuel. The last notable feature of the BV 144 was the defrosting system located at both wingtips and the tail section. The system would have allowed the tips and tail to stay warm using heated air provided through an oil burner.

Operators

  • Nazi Germany – The BV 144 was intended to be used by the Deutsche Lufthansa, and possibly even the Luftwaffe as an advanced airliner meant for short-medium distance routes.
  • France – The French took over both prototypes of the BV 144 once the Germans retreated out of France and continue development of the plane postwar for a while before ultimately scrapping the project in the end.

Blohm & Voss BV 144

Wingspan 88 ft 7 in / 27 m
Length 71 ft 6 ¼ in / 21.8 m
Height 16 ft 5 ¼ in / 5.01 m
Wing Area 947 ft² / 88 m²
Engine 2x BMW 801 MA (1600 hp)
Fuel Load 1900 L (Gasoline)
Minimum Weight 17416 lb / 7900 kg
Maximum Weight 28660 lb / 13000 kg
Cruising Speed 255 mph / 410 kmh at 13123 ft / 4000 m
Maximum Speed 292 mph / 470 kmh
Service Ceiling 29848 ft / 9100 m
Range 963 mi / 1550 km
Crew 1x Pilot

1x Co-Pilot

1x Radio Operator

Payload Regular:

18x Passengers

Maximum:

23x Passengers

Gallery

The prototype BV 144 seen in a side profile illustration
A “What-if” paint scheme depicting the prototype BV 144 if it had seen service with Lufthansa during the mid forties.

Sources

Gunston, B. (1980). The illustrated encyclopedia of propeller airliners. New York: Exeter Books. , Kay, A. L., & Smith, J. R. (2002). German aircraft of the Second World War: Including helicopters and missiles. London: Putnam. , Lepage, J. (2009). Aircraft of the Luftwaffe: 1939-1945: An illustrated guide. Jefferson, NC: McFarland. , Images: Side Profile Views by Ed Jackson – Artbyedo.com

 

Republic of China XP-0

republic of china flag Republic of China (1942)
Prototype Fighter Plane – 10 Built

The 1st AFAMF XP-0 was a prototype fighter designed by China during the early stages of World War 2. Based off of the American Curtiss Hawk-75’s (P-36 Hawk) design, the XP-0 was essentially an improvement with performance increases. Relatively obscure to the Western world, the XP-0 is a unique plane to study as it came from the Republic of China, a nation with relatively poor industrial capabilities and a heavy reliance on aid from other countries such as the USA and USSR.

XP-0 colorized by Michael J.

History

Prior to the start of the Second Sino-Japanese War, the ROCAF (Republic of China Air Force) was looking to modernize their equipment. Seeing an opportunity for economic gain, many American aviation companies such as Beechcraft, Consolidated, Ford, and Curtiss began to send out demonstration aircrafts and salesmen. On June 8th 1937, the first Curtiss H-75H (serial number 12327) made its way to Nanjing (Nanking) for demonstration flights. Flown by Curtiss representative pilot, Peter Brewster, in August,  Chinese air force officials were very impressed with the characteristics of the H-75H and immediately bought the demonstrator aircraft. After more test flights, the decision to import more H-75s was approved, and as such, thirty models of the H-75M (serial numbers 12625-12654) with non-retractable landing gears were bought and imported some time between May and August, 1938. The final H-75 to be bought by the ROCAF is a H-75Q (serial number 12898), which arrived in Rangoon (nowadays Yangon) in December, 1938, where it was test flown against various other aircrafts in service with the ROCAF such as the Soviet Polikarpov I-15 and I-16 and proved superior to them.

When the Second Sino-Japanese war began on July 7th, 1937, there became an obvious increase in demand for combat aircraft. In 1940, wanting to take advantage of the H-75’s advanced design, the executive of the 1st AFAMF (Air Force Aircraft Manufacturing Factory) Zhu Jia Ren (朱家仁) proposed the idea to design a fighter plane based on the H-75 – the H-75 itself was no longer provided to China as the US could no longer supply China with weapons without ruining their diplomatic relationship with Japan. Once Zhu was given the go-ahead by the Chinese government, work immediately began on designing a fighter based on the H-75. After a very lengthy design stage, the final draft of the design was completed, allowing for a prototype to be built in 1942. After the prototype was manufactured, it was ready for flight evaluations. As such, the prototype was transferred to Yanglin (杨林) Airfield located near Kunming (昆明). The test pilot chosen was Lieutenant Wang Zhong Xiao (王中校), an experienced pilot who had considerable flight time in H-75 Hawks. Xiao was able to take off successfully without any problems, and flew around the airfield before coming down to land. During the landing, Xiao noticed that the XP-0’s landing speed was considerably higher than the H-75’s, and this threw him off. The left gear leg of the XP-0 hit the ground first, and caused the plane to tumble and crash into the ground. The wings, rear fuselage and landing gear were all torn off, with the cockpit area smashing onto the ground and leaving the plane belly up. Miraculously, Xiao was able to climb out of the cockpit unharmed. The conclusion of this mishap was that it was caused by pilot error. Xiao, however, was not punished or berated for this. Instead, the design team was even more determined and encouraged to keep on improving and polishing the design seeing as according to Xiao, the XP-0 performed similar to the H-75 in some aspects, but superior in other aspects such as speed.

After further adjustments and improvements to the XP-0 design, two examples were produced some time in 1944, with two more following in early-mid 1945. There are many indications that more test flights were made which were met with no mishaps and positive results, but the details of these alleged flights is unknown. After the victory against Japan, the ROCAF began to demobilize in 1946. Due to this, the XP-0 was no longer seen as a top priority, and new materials were not supplied to the 1st AFAMF for production of more examples. However, the 1st AFAMF used materials in storage to produce five more XP-0 fighters before stopping production once and for all. In total, ten XP-0 fighters were produced including the first one from 1942 to 1946. Unfortunately, the fate of these other nine fighters produced is not known, much like many other indigenous Chinese planes designed during the war. It would be reasonable to assume that these were probably destroyed or scrapped by the Nationalists to prevent them from being captured by the Communists, or the Communists captured the prototypes but destroyed them soon afterwards.

Design 

As mentioned earlier, the XP-0’s design was based off of the Curtiss H-75’s design. It is not a direct copy of it, although they share many aesthetic characteristics. The first XP-0 prototype was constructed using parts from crashed H-75s, namely the landing gears, the cockpit’s instrumental gauges (airspeed, oil pressure, fuel load, etc.), and perhaps spars. It is unknown to what extent the XP-0 used recycled or salvaged parts from the crashed H-75s. The fuselage itself is indigenously made using a combination of metal and wood taken from the Outer Mongolia region of China. With regards to armament , many sources stated the armament would consist of a single .50 calibre (12.7x99mm) M2 Browning and a single .30 calibre (7.62x63mm) M1919 Browning. However, this is debated. (See the Common Misconceptions section below) The first XP-0 prototype was unarmed and it is unknown whether or not the other nine machines were armed. Unfortunately due to relatively scarce reliable sources available publicly, the finer details of the XP-0 are unknown. As for the other nine examples produced between 1944 and 1946, it is unknown whether or not they continued using salvaged H-75 parts or indigenously produced parts. Seeing as the war situation gradually improved in China’s favor, it is not unreasonable to assume that the quality of the other machines went up too.

Common Misconceptions

One of the most common mistakes people make is calling the XP-0 either the “Chu X-PO”, “X-PO” or anything similar. The official designation is “XP-0”, as the ROCAF structured their designation system similar to how the USAAF structured theirs. It would be illogical to have a such a name deviation for this project.

Another misconception is that the XP-0 was a stepping block to develop the XP-1, meaning that the XP-0 was some sort of a “prototype” to the XP-1. However, these two machines are not related in any way except for the fact that it is being manufactured by the same factory and both share the common “XP” (研驱) designation, which refers to a prototype plane.

The last notable dilemma to discuss is the armament of the XP-0. Many sources state that the XP-0 was to be armed with two or four 20mm Madsen cannons or Hispano-Suiza cannons while many other sources states that the intended armament was one 12.7mm M2 Browning and one 7.62mm M1919 Browning machine gun. While it is not impossible that  cannons were to be used, it is very unlikely, as the airframe of the XP-0 was based off of the H-75A, and the H-75A was designed and armed with machine guns. The most probable and reasonable armament would therefore be the single M2 Browning and M1919 Browning setup. With the deviation of these armament setups, it is possible that the nine machines produced from 1944 to 1946 may have been armed with different guns.

Operators

  • Republic of China – The XP-0 was going to be solely operated by the Republic of China Air Force.

1st AFAMF XP-0*

* – Estimated Dimensions and Statistics

Wingspan 37 ft 4.8 in / 11.4 m
Length 28 ft 8.1 in / 8.74 m
Height 9 ft 3.0 in / 2.82 m
Engine 1x Pratt & Whitney R-1830-S1C-G (1200 hp)
Empty Weight 4409 lb / 2000 kg
Maximum Weight 6283 lb / 2850 kg
Cruising Speed 280 mph / 450 kmh
Range 1143 mi / 1840 km
Maximum Service Ceiling 29527 ft / 9000 m
Crew 1x Pilot
Armament 1x 12.7x99mm Browning M2

1x 7.62x63mm Browning M1919

Sources

中國飛機和直升機製造家 – 朱家仁及他所研製的飛機和直升機. (n.d.). Retrieved April 07, 2018研驱-0/1/2. (n.d.). Retrieved April 07, 2018研驱零. (n.d.). Retrieved April 07, 2018Green, W., & Swanborough, G. (2004). The Complete Book of Fighters: An Illustrated Encyclopedia of Every Fighter Aircraft Built and Flown. London: Greenwich Editions.Gang, W., Ming, C. Y., & Wei, Z. (2011). Zhong Guo Fei Ji Quan Shu /中国飞机全书 / [Encyclopedia of Chinese Aircrafts] (Vol. I). 北京: Hang kong gong ye chu ban she.,Colorized Images by Michael J.

 

Project 337

Soviet Union (1941)
Biological Weapon – 1 Built

With recent study trips to Russia, the Plane Encyclopedia team has been working closely with the Russian Archives to record and scan aircraft performance data and various other aviation related documents. While doing this, the team has accidentally rediscovered a series of then-classified documents regarding a secret biological weapon designed in 1941 intended to be used on Berlin in an attempt to stop or at least delay the German advance on Moscow. Classified “Project 337” by the Soviets, the weapon would have been able to bring havoc on any city it was deployed on. Come read the story of the newly discovered Project 337!

History

In the early stage of Operation Barbarossa during the shift of fall to winter, the Soviet high command became increasingly worried and desperate for a way to halt or at least delay the seemingly unstoppable German advance. On September 29th of 1941, a top secret meeting was held at the Kremlin to discuss the current losses of the Soviet Union, and how to replace the lost equipment. With mostly desperate ideas such as using outdated equipment such as 19th century rifles and cannons taken from stockpiles. Finally, a serious and feasible idea was brought up, which was to bomb Berlin with biological weapons, causing the city to plunge into chaos, and to warrant the retreat of the Germans. With Stalin liking the idea, he immediately agreed and ordered the project to be finished no later than November 29th.

Unfortunately, the dimensions, location, team and materials used to develop Project 337 is unknown as the documents that specifies these are still classified and withheld by the Russian government. What is known however, is that the disease which would be used in Project 337 was tularemia.

This rather unclear photo shows what appears to be the finished Project 337 prototype, resembling a huge metallic peanut with the black canopy.

With extensive research in the Russian archives, two photos of Project 337 were able to be obtained. The first photo shows the roof of the weapon, which consisted of a bowl shaped canopy with more than a dozen holes. This would have been how the tularemia bacteria would be released. The second photo shows what seems to be the finished Project 337 prototype, which looked like a huge metallic peanut with the black canopy.

The upper section of the weapon, which consisted of a bowl shaped canopy with more than a dozen openings. This would have been how the tularemia bacteria would have been released.

On December 1st of 1941, Project 337 was completed and was now ready to be tested on Berlin. To carry such a weapon, the Soviet Air Force began looking for a capable heavy bomber which would be able to fly at tall heights. Although scarce, the bomber chosen was the Petlyakov Pe-8 bomber. A single Pe-8 was transferred from the Far East Regiments and modified to carry Project 337. As for personnel, experienced pilots Lieutenant Igor N. Timoshenko, Junior Lieutenant Dima I. Pokryshkin and Lieutenant Mikhail Gorkin were chosen to complete the task of dropping the prototype biological weapon on Berlin. These pilots were not told of the contents they were carrying, and was only instructed to fly to Berlin, drop the payload and return to base as the Soviets still wished to maintain the secrecy of the project.

On December 5th, Lieutenant Igor N. Timoshenko, Junior Lieutenant Dima I. Pokryshkin and Lieutenant Mikhail G. Gorkin took off in the Pe-8 carrying Project 337 at 8:31 PM from an undisclosed secret airfield. With the intent of maintaining stealth, the Pe-8 crew would have maintained radio silence in order to not get detected. Approximately 1 hour and 14 minutes into the flight, the Soviet ground crew were surprised to receive an emergency radio call from the aircrew. According to the recently declassified Soviet documents, the ground crew reported that Lieutenant Gorkin shout in the radio in panic that the Pe-8’s inner starboard engine caught fire, and that the plane was rapidly losing altitude. Lieutenant Gorkin decided the best thing to do was to perform an emergency landing, and he made this decision known to the ground crew. Unfortunately, the documents stated that contact was lost with the crew during the botched emergency landing. One of the documents dated April 1st of 1944 stated that efforts to locate the Pe-8 has failed, and that the plane likely crashed into a body of water. Due to the loss of the sole bomb, tests were unable to be completed and the project was set back. This led to the eventual abandonment of the project as the Soviets couldn’t afford to spend more time development such a weapon.

The final document which referenced Project 337 dated April 20th of 1948 mentioned that the incident which caused the destruction of the Pe-8 was improper maintenance. It is said that the mechanics responsible for the maintenance were executed, while the radio crew were sent to the gulag. Timoshenko, Pokryshkin and Gorkin’s families were all sent a letter stating that they died in combat as heroes. In conclusion, Project 337 can be considered a failure. With the current evidence that the Plane Encyclopedia team has, it is reasonable to assume that the Pe-8 carrying Project 337 is perhaps still out there buried beneath layers of mud, sand, or water, never to be seen by mankind again.

Sources

Rep. No. Поддельный источник, используемый для апрельских дураков (04.01.1944) (1944).

Rep. No. Полностью реальный источник, а не подделка (04.20.1948) (1948).

Doc. No. Я люблю Энциклопедию (01.14.1943).

 

Kawasaki Ki-88

 Empire of Japan (1943)
Prototype Fighter Interceptor – 1 Built

The Kawasaki Ki-88 was a fighter interceptor designed in 1942 with the intent of intercepting enemy aircraft heading towards vital military locations. The Ki-88 would never see service, as it was cancelled in 1943 after a mockup and partial prototype were constructed. Although considered by many to be the Japanese copy of the American Bell P-39 Airacobra due to the exterior aesthetic similarities, this is only speculation.

History

The origins of the Kawasaki Ki-88 began in August of 1942 when Tsuchii Takeo, a designer for Kawasaki, responded to a design specification put forward by the Imperial Japanese Army Air Service (IJAAS). The IJAAS determined that they needed an interceptor aircraft that would defend important military assets like airfields, gun emplacements, and others. The specification also stated that the aircraft had to be heavily armed, provide a stable gun platform and be easily flyable by new pilots.

Takeo began work on the Ki-88 and chose to use a 37mm Ho-203 cannon as the plane’s primary armament, with two 20mm Ho-5 cannons to complement the Ho-203. The placement of the guns prompted Takeo to place the engine behind the cockpit. Many sources state that this was done to copy the American Bell P-39 Airacobra, but that claim is debated. The P-39 Airacobra was in service at the time the Ki-88 was developed, but saw limited service with the United States. It did however, see service during the Battle of Guadalcanal. The Japanese were certainly aware of its existence and possibly captured an example of the P-39. If they did indeed capture an example, Takeo could have simply copied the gun and engine placement. It is important to note that such a “rear-engine” fighter configuration was a rarity in plane design at the time. Another common theory is that Takeo came to the same conclusion as H.M Poyer (designer of the P-39) did during the planning phase and designed the plane without copying the P-39. Other than the engine and gun placement, the two planes are quite dissimilar.

Takeo completed the Ki-88’s design in June of 1943. A full scale mockup and prototype were in the works in mid/late 1943, and estimated that the prototype would be completed in October of 1943. However, after the mockup and plans were inspected by representatives of the IJAAS, it was concluded that the Ki-88 had no real improvements over other designs of the time, and the top speed was only slightly better than the Kawasaki Ki-61 after calculations. The IJAAS immediately lost interest and ordered Kawasaki to cease all work on it.

Design

The Ki-88 was a single seater, single engine fighter powered by a Kawasaki Ha-140 engine producing 1,500hp while driving a propeller using an extension shaft. The radiator was placed under the cockpit at the bottom of the fuselage. There was an air intake placed beneath the fuselage on the left to provide cooling for the supercharger in the Ha-140.

The Ki-88 used a conventional landing gear, in which the main wheels could be retracted into the wings while the tail wheel stayed fixed. There was a fuel tank in each of the wings, beside the landing gear wells.

The size of the Ho-203 canon prevented Takeo from placing the engine into the nose which led him to place it behind the pilot’s cockpit, much like the American P-39 Airacobra. Moving the engine to the back of the cockpit was a smart move, as it theoretically would have made the plane a more stable gun platform. Under the Ho 203, on both sides of the nose, there were two 20mm Ho-5 cannons.

Operator(s)

  • Empire of Japan – The Ki-88 was supposed to have been operated by the Imperial Japanese Army Air Service, but never did so due to the design being deemed as inferior to the Ki-61 and was thus cancelled.

Kawasaki Ki-88*

*Estimated Performance

Wingspan 40.6 ft / 12.37 m
Length 33.4 ft / 10.18 m
Height 13.6 ft / 4.14 m
Wing Area 8,598 ft² / 27.49 m²
Engine 1x Kawasaki Ha-140 (1,500hp)
Empty Weight 6,503 lbs / 2,949 kg
Loaded Weight 8,598 lbs / 3,899 kg
Climb Rate 6 minutes & 30 seconds to 16,404ft (5,000m)
Maximum Speed 373 mph / 600 kph at 19,685ft (6,000m)
Range 745 mi / 1,198 km
Maximum Service Ceiling 36,089 ft / 11,000 m
Crew 1x Pilot
Armament 1x 37mm Ho-203

2x 20mm Ho-5

Gallery

 

Sources

Performance. Report No. 19b(4), USSBS Index Section 2 (Tech. No. 19b(4)). (n.d.)., Pacific Survey Reports and Supporting Records 1928-1947 Kawasaki Aircraft Industries Company, Ltd. (Kagamigahara, Gifu plant), Dyer, Edwin M. Japanese Secret Projects: Experimental Aircraft of the IJA and IJN 1939-1945. Classic, 2013.Francillon. (1987). Japanese aircraft of the Pacific war. Annapolis, Md: Naval Institute Press., Images: Side Profile Views by Ed Jackson – Artbyedo.com

 

Beechcraft XA-38 Grizzly

usa flag USA (1944)
Prototype Attack Plane – 2 Built

Colorized photos by Michael J.

The Beechcraft XA-38 Grizzly was an experimental attack aircraft stemming from a USAAF requirement for a two seated attack bomber. Two prototypes were constructed between 1944 and 1945, and saw extensive testing within the US. The Grizzly showed promising performance, but was ultimately cancelled due to the engines intended for use was given priority to the Boeing B-29 Superfortress and the inevitable victory of the Allies.

History

Bottom view of Beechcraft XA-38 (S/N 43-14407) in flight. (U.S. Air Force photo)

In 1942, the United States Army Air Force (USAAF) issued a requirement for a two seater attack bomber. Beechcraft was quick to respond, and proposed their design to the USAAF. The USAAF was very interested in the design, and ordered two prototypes to be constructed in December of the same year after granting the contract to Beechcraft. In anticipation of the two prototypes, the USAAF assigned serial numbers to them, being “43-14406” and “43-14407”.

 

Beechcraft specifically designed the Model 28 to be able to destroy gun emplacements, ships, armored vehicles and bunkers while keeping great maneuverability and able to remain airborne after being damaged. All of this would be done by the addition of a powerful 75mm T15E1. The task of developing the Grizzly was given to a team led by Bill Cassidy with Jess Vint and Alex Odevseff in charge of designing the armaments, Bill Irig in charge of the control surfaces, Gus Ericson in charge of the design of wings, Mervin Meyers in charge of hydraulics, Ralph Harmon in charge of the landing gear structure and Noel Naidenoff in charge of the engine compartment. The Grizzly is common thought to be a modified Model 18 design, but this is untrue. The Grizzly did take inspirations from the Model 18, though.

Beechcraft XA-38 during ground vibration tests. Tests were set-up to determine natural frequencies excited during engine operation. (U.S. Air Force photo)

The first Grizzly (43-14406) was delivered to the Army Air Force and flown on May 7th of 1944 by test pilot Vern L. Carstens. The first test flight went relatively well except for an unplanned touch-and-go during landing. This was due to Carsten’s inexperience with landing such a large plane. The first prototype had no armaments installed, but had a wooden mockup of the 75mm T15E1 cannon. In the next few test flights, the Grizzly proved itself to be very aerodynamically stable, and made a good impression with the designers. A memorable flight test includes a performance comparison between the Grizzly and a recently manufactured North American P-51B. The Grizzly and P-51B were put in a mock pursuit, and the P-51B was reported to have been unable to keep up. Afterwards on July 7th of 1945, the first Grizzly was transferred to Wright Field to be used by the USAAF. It then participated in 38 test flights from between October 13 and October 24 of 1944 flown by Captain Jack W. Williams. Williams affectionately noted that the Grizzly was a great aircraft and “very maneuverable” for an aircraft of its size. It is also interesting to note that the turrets on the first Grizzly were dummies.

Front view of Beechcraft XA-38 (S/N 43-14407) in flight. (U.S. Air Force photo)

The second Grizzly (43-14407) had its maiden flight on September 22nd of 1945, once again piloted by Carstens. The second prototype was intended for armament testing, so it had all weapons fitted. The 75mm T15E1 prototype cannon was already successfully tested the year before on July 1st. The second Grizzly flew a total of 38 hours afterwards in tests at Eglin Field in Florida.

As successful as the Grizzly was, it would never reach mass production status because of two reasons. The first reason was that the R-3350 engines were in short supply, as the Boeing B-29 Superfortress had top priority for the engines. Second, the war situation was already in America’s favor, thus cancelling out the need for such an aircraft. As a result, both of the Grizzlies were retired from active service. One was scrapped while the other one was transferred to the Davis-Monthan Airfield in Arizona, meeting an unknown fate.

Design

The XA-38 Grizzly was an all metal, two seat, twin engined semi-monocoque plane with cantilever wings, conventional landing gears, oleo-pneumatic shock absorbers and hydraulic brakes. It was powered by two Wright R-3350-43 Duplex Cyclone engines, the same engine that powered the Boeing B-29 Superfortress. The propellers measured at 4.32m (170in) each in diameter.

The plane used flush riveting and butted skin joints to give the plane its pristine, shiny look. The foil used to construct the wings were derived from the NACA 23000 series which was good for high and low speeds. The engine hub was made from stainless steel and aluminum alloy. The oil coolers were placed in the wings. Four fuel tanks were installed in the wings with a capacity of 2,422 litres (640 US Gallons). Two self-sealing fuel tanks were also placed behind the cockpit which can carry 681 litres (185 US Gallons) if needed to. There were pumps and connectors installed onto the tanks, which would stop fuel flow if the tanks took damage.

Beechcraft XA-38 (S/N 43-14407, the second and last XA-38 built). (U.S. Air Force photo)

As for armaments, the XA-38’s 75mm T15E1 was the defining feature. Could carry 20 rounds fed by a Type T-13 feeding system. There would be a Type N-6 reflector sight to help the pilot aim. The cannon would fire every 1.2 seconds if the pilot pressed the trigger button. Two .50cal (12.7mm) M2 Browning machine guns were installed under the cannon with 500 rounds each. The entire nose section of the XA-38 could be unhinged, where mechanics can easily access the guns for maintenance.

The Grizzly had two turrets, one located on the top of the fuselage and one on the bottom. The turrets were manufactured by General Electric and had two M2 Brownings each with 500 rounds. These two turrets were controlled by a single gunner seated in the rear fuselage. He would aim the guns with a periscope to control the turrets. Interestingly enough, the turrets can also be fixed to fire forward to accompany the T15E1. Ordinance wise, the XA-38 was designed to carry a wide range of things. It could have carried bombs, napalm, torpedoes, fuel tanks, smoke tanks and depth charges.

Operators

  • United States of America – The USAAF was the sole operator of the XA-38. The USAAF extensively tested the XA-38, and concluded it was a success. However, the XA-38 never reached mass production status.

Beechcraft XA-38 Grizzly

Wingspan 64 ft 4 in / 20.52 m
Length 51 ft 9 in / 15.77 m
Height 15 ft 6 in / 4.72 m
Wing Area 626 ft² / 58.15 m²
Engine 2x Wright R-3350-43 Duplex Cyclone (2,300hp)
Fuel Capacity 640 US Gallons / 2,422 L

Additional Tanks: 185 US Gallons / 681 L

Maximum Takeoff Weight 35,265 lbs / 15,996 kg
Empty Weight 22,480lbs / 10,197 kg
Wing Loading 56.3 lb/ft² / 275.1 kg/m²
Power Loading 7.67 lb/hp / 3.48 kg/hp
Climb Rate 2,600 ft/min / 792 m/min
Maximum Speed 330 mph / 531 km/h at Sea Level

348 mph / 560 km/h – at 5,000 ft / 1,525 m

370 mph / 595 km/h – at 17,000ft / 5,180m

Cruising Speed (75% Throttle)

289 mph / 465 km/h – at Sea Level

350 mph / 563 km/h – at 16,000 ft / 4,875 m

Range 1,625 mi / 2,615 km – at 225 mph / 362km/h

745 mi / 1,200 km – at 289 mph / 465 km/h

Service Ceiling 29,000 ft / 8,840 m
Crew 1x Pilot

1x Gunner/Observer

Forward Firing Armaments 1x 75mm T15E1 (20 rounds)

2x 12.7mm M2 Browning (500 rpg)

Defensive Armaments 2x 12.7mm M2 Browning (Upper Turret) (500 rpg)

2x 12.7mm M2 Browning (Belly Turret) (500 rpg)

Ordinance Planned Options:

  • Bombs
  • Fuel tanks
  • Napalm
  • Torpedoes
  • Depth Charges
  • Smoke Tanks

Gallery

Grizzly Prototype 314407 – armed with two 500 lb bombs

Sources

Beechcraft XA-38. (2008). National Museum of the US Air ForcePearce, W. (2013). Beech Aircraft Company XA-38 Grizzly. Old Machine Press.Pelletier, Alain J. (2005). Beech aircraft and their predecessors. Putnam, Images:  Side Profile Views by Ed Jackson – Artbyedo.comColorized Images by Michael J.