Lost Aircraft, Part 1

by Jim "Twitch" Tittle

Article Type: Military History
Article Date: November 20, 2002


Aichi S1A1 "Denkoh" Night Fighter
This twin engine night fighter was begun as an experiment in 1943. Specifications for long-range, high ceiling and ample weaponry were foremost. Early airborne radar was to be incorporated as well, though type is unknown.


The S1A1 had a 49.2-foot fuselage housing a crew of two. The pair of 1,990 HP Nakajima Homare 22 18-cylinder radials sat on the 57.4-foot wings. A top speed of 366 MPH was estimated while cruise was to be 276 MPH. It was realized that exhaust driven turbo chargers were needed to produce the needed altitude performance but like many other Japanese prototypes of the late war they were not forthcoming. If attached presumably the ceiling would have been 39,370 feet. A range of 994 miles was projected. Performance was on par with other big twin engine planes being worked on in Japan late in the war like the Mitsubishi KI 83. Weights were similar too with a 16,104 lb. empty and 22,396 lb. loaded weight.

Forward-firing armament was the same as the KI 83 with two 30 mm Ho-105 and two 20 mm Ho-5 cannon. But the difference was rear defensive weaponry. The S1A1 had a power turret with a pair of 20 mm Ho-5s as well. Provisions for a 550 lb. bomb load were made.

The prototype machine was nearly complete but was destroyed by fire from an air raid in June 1945.

Rikugun Kokukosho KI 93
Another lost number in the Japanese Air Force series of KIs is this twin engine ground attacker.

The 2-man crew rode forward in the 46.6-foot fuselage. The 62.3-foot wings mounted a pair of Mitsubishi Ha211M 18-cylinder radials of 1,970 HP each. Loaded weight was a bit heavier than similar designs of the time at 25,168 lbs. Empty it was 17,296 lbs.

KI 93

Maximum speed was high at 388 MPH with cruise at 217 MPH though range is unknown. Ceiling estimates were a high 39,534 feet. Two 20 mm Ho-5 cannon were supplemented by a 57 mm Ho-402 . One 12.7mm Ho-103 machine gun defended the rear and 551 lbs. of bombs could be carried.

No production was undertaken of this clean design reminiscent of the Me 210/410.

Kawasaki Ki-78
Known as the “Ken” in the Allied name designations of Japanese aircraft, this bird was an experimental exercise extension of the KI 61 Hein in the use of the Daimler-Benz DB 601A V-12 in a lighter package. Like the KI 61 “Tony” the Benz engine would have been a Kawasaki-built power plant with 1,550 HP. In many respects it was a cleaner design shape than the KI 61.

KI 78

Overall it was smaller and lighter than the KI 61 models with a length of 26.6 feet, a span of 26.2 feet, empty weight of 4,246 lbs. and a loaded weight of 5,060 lbs. (The KI 61 IIb’s span was 39.23 feet and it weighed 8,333 lbs loaded.)

A methanol/water injection boost system gave the interceptor a high 435 MPH top speed but a short range of just 373 miles. Ceiling was similar to the KI 61 at 36,274 feet. No armor or armament was attached during testing. Certainly this would have affected weight and performance.

By the end of 1944 the supplies of Kawasaki V-12s (called the Ha.40) were small due to factory damage from air raids and the KI 100 was made using the Mitsubishi Ha.112 radial that was abundant. Grafted onto KI 61 airframes and later on new ones, The KI 100 filled the niche precluding further work on the KI 78.

Mitsubishi G7M1 "Taizan" (Type16)
Beyond the excellent G8M1 “Rita” 4-engine bomber tested in the post-war US, the Type 16 project was drawn up for a high-speed bomber able to carry a lighter payload shorter distances. A crew of five rode in a comfortable 65.6-foot fuselage. Four Mitsubishi Ha.42 Model 31 18-cylinder radials of 2,400 HP each turned on the 82-foot wings. All up the compact bomber weighed 35,200 lbs.

Like the Rita this ship would be quite fast at 345 MPH but with a shorter range of 1,726 miles.

Defensive armament proposed was two 20 mm cannon and six 13 mm machine guns Bomb load variables could be a 1,760-lb. bomb or torpedo, two 1,100-lb. bombs or six 550-lb bombs.

This project was cancelled due to shortages and long lead time to completion.

Kawanishi K-100 (Type17)
Another contender for a high speed long-range bomber that was fulfilled by the G8M1 “Rita” was a Kawanishi proposal. This thing was small like the Mitsubishi Type 17 with a crew of four in a short 50-foot fuselage. Four Nakajima Mamoru-Kai 18-cylinder radials each with 2,300 HP mounted on the 75-foot wings. Weighing just 30,000 lbs. loaded this thing could scream at 376 MPH top speed and cruised at 230 MPH for 3,450 miles range. A ceiling of 30,732 feet was projected.

Armament was just three 20 mm cannon a 1,760-lb. torpedo or bomb of the same weight.

This one never proceeded beyond preliminary designs.

Kyushu Q1W1 "Tohkai" Model 11
Codenamed “Lorna” this anti-submarine aircraft was an old design from 1938. A crew of three resided in a 39.3-foot fuselage. The plane had a 52.5-foot wingspan mounting two 510 HP Hitachi Tenpu 31 9-cylinder radials.

Speed was not deemed a critical factor for anti-sub duties and the slow 206 MPH top and 138 cruise/loiter speeds were ample for the time. The plane weighed just 10,439 lbs. loaded and could travel 1,500 miles. Ceiling was not high nor did it need to be at 14,730 feet.


It carried 550-lbs of bombs and mounted a 20 mm firing forward and a 7.7 mm machine gun on a flexible mount in the lower glazed observation nose. A rudimentary Type3 Model 1 MAD (KMX) magnetic anomaly detector equipped the plane but very few were built or used.


Caproni Vizzola F.6Z
The Italians had a very short war, as it was, with their capitulation to the Allies in late 1943. But before they did two prototypes of a remarkable plane were done. The second example used a 15,000 HP Isotta-Fraschini R.C.25/60 Zeta 24-cylinder X-type engine in the 29.5-foot fuselage. It had elliptical wings spanning 38.8 feet.

The plane was relatively heavy at 9,021 lbs. loaded but fast with a 391 MPH top speed at 16,405 feet. Range was 850 miles.

Two 12.7 mm SAFAT machine guns were to be carried but all work was halted when the Armistice was signed.

Reggiane Re-2007
Early Italian jet experimentation with indigenous power plants, such as the Caproni-Campini N.1 that used a 900 HP Isotta-Fraschini piston engine and ducts to produce jet thrust, were lackluster but Italy almost had a potent jet. The 1943 Reggaine Re-2007 was to use the Junker Jumo 004B with 1,980 lbs. thrust.

The open exchange of ideas and material between Germany and Italy saw interesting applications in the aviation field such as using Daimler-Benz piston engines on Italian prototypes. When the Jumo was seen as a possible source of power Reggaine laid out a small fighter design. For the time, right before Italy’s capitulation, the craft looked quite a lot like contemporary Reggaine piston engine fighters which makes sense. Even the classic Reggaine tail was present on the oval-shaped 29.5-foot fuselage. Though the tail was non-swept the wings spanning 31.1 feet did have a slight sweep.

A certain Hauptmann Bohm, was the Luftwaffe's senior engineer at the Reggiane plant, but even he was unable to obtain a positive decision concerning the supply of the two Junkers Jumo 004B's which had been promised by Berlin. On January 7, 1944, Reggaine engineer Roberto Longhi wrote to Count Caproni, requesting that he intervene with the Germans as design work had diminished. Much of the rear fuselage, wing spars, ribs, undercarriage and the cockpit were already built but because of the inability to obtain adequately detailed dimensional specifications about the engine work once again halted.

In October 1944 the finished components were transported to the Caproni plant at Taliedo, where they remained until the end of the war. They were ultimately shipped to the US. The two Jumo 004B engines were sent to Italy, but were allegedly sold for scrap in Milan immediately after the withdrawal of German forces in Italy.

Re 2007

Keeping with the Italian lust for compact planes of high maneuverability the Re-2007 was that weighing just 7,788 lbs. loaded compared to around 14,000 lbs. for the Me 262. Its pair of 004Bs were buried in the fuselage for a very post-war look. The pilot’s bubble canopy sat adjacent to the leading edge of the wings.

Maximum speed was estimated to be about 630 MPH while a range of 931 miles was estimated. Four 20 mm MG 151 cannon was to be the armament.


Mikoyan I-250 (N)
Mixed power was not the exclusive property of Germany, which saw many combinations of motive thrust in its designs. In Russia some La-7s were produced with liquid fuel rockets in the rear fuselage for combat boost but the ramjet seemed to hold more promise.

In 1943 Artem Mikoyan began work on a fighter using a V-12 to pull it and a ramjet to push it. A Klimov VK-107A 0f 1,650 HP drove a 3-bladed prop and a compressor to boost airflow to a rear-mount ramjet. The pilot sat well back at the wing’s trailing edge of the 26.9-foot fuselage of the loaded 8,666-lb. plane. Wingspan was just 31.1 feet.

I-250 mixed power

The I-250 (N) flew in March 1945 and hit 497 MPH. The ramjet provided an additional 660 lbs. of thrust translating to 62 MPH for ten minutes. The ship could attain 385 MPH at sea level and 513 MPH at 22,965 feet. Time to 16,405 feet took 3.9 minutes and a ceiling of 39,240 feet was achieved with a range of 857 miles.

Three 20 mm G-20 cannon were used. One sat between the cylinder banks with the others alongside the engine.

With collapse of Germany and the wealth of technical data retrieved, designs of pure jet were emphasized and Mikoyan concentrated on the future MiG 9 jet design. The I-250 was designated MiG 13 and sixteen were produced but were retired by 1948.

Mikoyan-Gurevich I-270
Early in 1945 a target defense fighter design was handed down and the I-270 filled that role. Its design seems to borrow in the Me 263 but is less radical having straight wings measuring 29.5 feet in span. The pilot sat well forward of the 3,197 lb. thrust two chamber RD-2M-3V rocket motor in the 29.25-foot fuselage.

I-270 is Me 263 clone

The plane first flew in December 1946 and had a pressurized cabin. A second prototype flew in early 1947 but developing pure jet power eclipsed the rocket interceptor. The little planes weighed 9,083 lbs. loaded and could hit 621 MPH at sea level and 582 MPH at 49,215 feet. It could climb to 32,810 feet in 237 minutes but with both rocket chambers lit its endurance was just 4.25 minutes of power.

Two 23 mm cannon and eight RS-82 rockets were to arm the fighter.

Bisnovat SK-2
It is curious what the Russians were looking for in the way of performance when they didn’t pursue production of this all-metal fighter in 1939-40. A study of high speed wings resulted in this craft whose purpose was to make the smallest possible package housing a V-12 for power.

The SK-2 was 27.1 feet long and had only a 23.95- foot wingspan. It was light at only 5,070 lbs loaded. The pilot sat way back behind the trailing edge of the wing to balance out the 1,050 HP Klimov M-105 V-12 in front.

SK-2 was fast for 1940

It could do 410 MPH at 16,405 feet and 401 MPH at 8,860 feet and climb to 16,405 feet in 4.3 minutes. Endurance was forty-five minutes. But even this performance seemingly did not warrant interruption of production of established types in 1940.


Martin-Baker M.B.5
The M.B.3 had grown from 1939 design that used a 2,020 HP Napier Sabre 24-cylinder horizontal-H engine with six 20mm cannon for armament. The second prototype was designated M.B.5 and was powered by a 1,900 HP Rolls Royce Griffon 83 that drove contra-rotating, 3-bladed props. The M.B.5 had four 20 mms.

M.B.3- quite P-51-ish

The 37-foot fuselage looked much like that of a P-51 due to the under-belly air scoop. But it featured a clipped 35-foot wingspan. The plane weighed 11,010 lbs. loaded and had a 460 MPH speed at 20,000 feet. Climb rate was 3,800 FPM and range was 1,100 miles.

Directional stability was poor and the plane was abandoned for jet development in 1947.

Westland Wyvern
This fighter bears the distinction of being the only British turboprop fighter to be used in combat which was during the 1956 Suez campaign. Originally laid out to use a 3,500 HP Rolls Royce Eagle 24-cylinder H type engine in 1945 it was designed to swap up to a turboprop when they became available. The 4,110 HP Armstrong Siddeley Python A.S.P.1 and the 4,500 HP R-R Clyde R.C.3 powered prototypes flew in 1949 with 550 MPH reached. With the Clyde discontinued the 4,110 HP A.S.P.3 was installed for production and contra-rotating props remained standard.

Wyvern was a hot lost number

The fighter was of normal proportions with a 44-foot wingspan and 42.25-foot length weighing 24,500 lbs. fully loaded and 15,500 lbs. empty. Four 20 mm Hispano Mk V cannon mounted in the wings and external ordnance of a torpedo, three 1,000-lb. bombs or eight 60-lb. rockets.
The last model the S Mk 4 was delivered to squadron in 1953 with 87 completed. This model could reach 456 MPH at sea level and climbed at 3,350 FPM to a ceiling of 28,000 feet. Range was 910 miles. Wyverns flew in front line service until 1958.


Arsenal VB 10
The French government ordered this strange plane off the drawing board in 1940 and work continued under the Vichy government throughout the war and went on when things reverted back to normal after the capitol was liberated in 1944.

The final design used two 1,150 Hispano-Suiza HS 12Z12/13 V-12s—one in the nose and one behind the pilot coupled together driving contra-rotating props. It finally flew in July 1945.

VB 10- 2 engines 1 propshaft

The wings spanned 50.75 feet and it was 42.6 feet long. Originally the second prototype flew with four Hispano 20 mms and six 12.7 mm Brownings but the production was revised to use the cannon only.

435 MPH was seen at 24,605 feet and range was 1,056 miles. Initial climb for the 19,533-lb. plane was dismal at 2,008 FPM. The original 200 projected for production ended with just four in 1948.

United States

Lockheed XFV-1
Long before the Harrier and other successful directionally ducted VTOL fighters there was the XFV-1 using an 5,850 HP Allison XT40-A-6 turboprop. This engine was to be replaced with a forthcoming unit of 6,955 HP.

A permanent, fixed landing gear for traditional takeoffs/landings was affixed under the prototype’s 36.9-foot fuselage. The cruciform tail was tipped with four tiny wheels which bore the plane’s weight when in the VTO position. The stubby wings spanned 27.5 feet and had 48 2.75-inch rockets in wingtip pods attached. Four 20 mm cannon were alternate weapons.


In flight trials with the US Navy the plane flew in 1953-54 successfully transitioning from vertical to horizontal flight. A top speed of 580 MPH was seen at 15,000 feet endurance was 1.17 hours. Initial climb was 10,820 FPM from the 16,221-lb. ship.

With the upgraded power plant being delayed and general performance lacking the project was cancelled. Landing vertically with the pilot on his back would have been produced blind maneuvers at any rate.

Convair XFY-1
Convair’s concept of the VTOL took shape as the XFY-1. It had delta wings spanning 27.7 feet and a 35-foot fuselage. It rested on small wheels in the wing tips and its huge tail fins. It used the same 5,850 HP Allison XT40-A-6 turboprop the Lockheed plane did planning for the later 6,955 HP engine.

Convair's XFY VTOL concept

Weight was close to the XFV-1’s at 16,250 lbs. loaded but it could manage 610 MPH at 15,000 feet. Climb rate and armament specifications were identical to the XFV-1. This plane never saw complete testing and the whole VTOL concept was shelved by the Navy.

Douglas F3D Skyknight
A forgotten veteran of the Korean War era is the Skyknight. This all-weather 2-seater was powered by two 3,250 lb. thrust WestinghouseJ34-WE-34 jets. It was first flown in early 1950 armed with four 20 mm cannon. Seating was a side by side layout and the plane had escape slides that dumped the crew out of the bottom of the 45.5-foot fuselage in lieu of ejection seats. It straight wings measured 50.75 feet.


In 1951 engines were upgraded to J34-WE 36s of 3,400 lbs. thrust good for 490 MPH at15,000 feet and a ceiling above 40,000 feet. Initial climb was 2,970 FPM and the Navy/Marine fighter could go 1,146 miles. The bulky plane weighed 26,731 lbs. loaded. Some of the approximately 300 built were later modified to carry missiles.

In Part 2 of Lost Numbers we will look at some more unknown birds from the pages of history.


Focke-Wulf FW 187
The Focke-Wulf Ta 154 Mosquito was well enough known as the German counterpart of the British plane of the same name. But before FW made their wooden wonder the FW 187 came into being. It came a year after the Bf 110’s first flight in 1936 and that was probably why no production was undertaken.

This twin engine craft had a pencil-slim 36.5-foot fuselage with the pilot in the extreme nose. The V1 and V2 prototypes were single seat but the Air Ministry instructed Focke-Wulf to make provisions for a second seat on subsequent examples. The V3, V4 and V5 were 2-seaters. The V6 also had upgraded to a pair of DB 500A V-12 with 1,000 HP each from Junkers Jumo 210Gs of 730 HP. They mounted below the 50.1-foot span of the wings. This plane reached 394 MPH in 1939.

FW 187A-0 FW factory defence

Three pre-production FW 187A-0s were completed with the Jumos good for 329 MPH at 13,780 feet complete with armor and guns. Two 20 mm MG FF cannon and four 7.9 MM MG 17s were all in the slim fuselage alongside the cockpit and in the nose. The 11,023-lb. craft had an initial climb rate of 3,455 FPM.

No reason why production was not commenced is known but the three A-0s were used as FW factory defense fighters in 1940-41.


  • Beale, Nick
    Air War Italy 1944-45,
    Airlife Publishing Ltd, Shrewsbury, UK 1996

  • Colby, Maj. C.B.
    Wings of Our Navy
    Coward-McCann, Inc. NY 1952

  • Green, Wm
    Jet Aircraft of the World
    Macdonald & Co., GB 1955

  • Green, Wm.
    The Complete Book of Fighters
    Salamander Books Ltd., UK 1994

  • Green, Wm.
    Fighters Vol. 3
    Doubleday, NY 1962

  • Gunston, Bill
    The Osprey Encyclopedia of Russian Aircraft
    Osprey Publishing, UK 1996

 Printer Friendly

© 2014 COMBATSIM.COM - All Rights Reserved