Remember when we used to fight Fascism? In memory of that time, let’s take a look at some of the stranger aircraft designs to come out of World War II.
There is no way I could fit every weird aircraft into a single diary. Just the Germans alone could fill two or three. I used three criteria for this list:
1. It had to have actually flown, at least as a prototype. That ruled out some of the really strange German designs like the Focke-Wulf Triebflügel.
2. It had to have flown operationally, been tested, or at least designed during the war. That gave me a lot to choose from.
3. I wanted to put it in here. I had to draw the line somewhere.
Boulton Paul Defiant
The Brits have built more than their share of oddball aircraft and the Defiant certainly meets that description.
In the years between the wars, it was believed that enemy bombers would likely arrive over England without fighter support. This makes some sense when you consider the relatively short range of fighter aircraft in those days.
Turreted fighters like the Defiant were meant to be interceptors of sorts. It was envisioned that they would fly alongside or underneath enemy bomber formations and duke it out like 18th Century ships of the line. I guess they never really got over Lord Nelson.
In practice this didn’t work out quite as planned. When war came, the German bombers usually had fighter escorts with them. The lack of any forward firing guns proved to be a bit of a problem for the Defiant. All that extra weight of the gunner and turret made for less than stellar performance.
A few Messerschmidt pilots did get a nasty surprise when they slid in behind a formation of what they thought were Hawker Hurricanes, which the Defiant bore a resemblance to.
The Defiant went on to serve as a night fighter, a role which it was better suited to.
Blackburn Roc
The Roc was like a crappier version of the Defiant for the Royal Navy. It had all the disadvantages of the Defiant plus it was slower by about 70 knots.
The Roc achieved exactly one kill versus a German JU-88 in its mercifully short operational career. It was then relegated to towing aerial gunnery targets. A few were even parked on airfields to serve as anti-aircraft guns.
Bell YFM-1 Airacuda
The US produced its share of odd designs and the Airacuda certainly fits the description.
Designed as a “heavy fighter” meant to attack enemy bombers, the YFM-1 Airacuda had two engines mounted in a pusher configuration.
A gunner sat in front of each engine, operating a 37-mm cannon. Oddly enough the cannons were actually aimed remotely by the copilot/navigator through an advanced (for the time) Sperry fire-control system. The gunner mostly got to keep the guns loaded and hope he never had to bail out because there was a propeller right behind him.
For self defense the YFM-1 had a pair of waist-mounted machine guns.
While in some ways ahead of its time, the Airacuda would have fared poorly in actual combat. It never came close to its design airspeed and would have been unable to catch most bombers of the day. The entire concept of a “heavy fighter”, at least in daytime, proved questionable at best. In practice they were usually easy prey for lightweight fighters.
Like many pusher designs the Airacuda’s engines suffered from overheating.
Finally, the YFM-1 had a fatal flaw in its electrical system. The entire system was powered by a single auxiliary power unit. If the APU failed (and it did) you lost the electric fuel pumps which kept the engines running (minor problem). You also lost your flaps, landing gear and hydraulics. Basically you were screwed.
A single Airacuda squadron actually saw brief operational service but the type was retired in 1940.
Ryan FR-1 Fireball
The Fireball was a pretty conventional looking carrier-based fighter but it was powered by both a piston engine and a jet engine. The piston engine was its primary source of power, being augmented by the jet when extra performance was required. A few other late 40s aircraft like the B-36 and P-2 Neptune also used mixed power.
The Fireball entered service with the US Navy in 1945 but never saw combat. While the idea was sound, the FR-1 proved not to be sturdy enough for the rigors of carrier operation. Only 66 were built and the type was retired in 1947.
Curtiss-Wright XP-55 Ascender
The “Ass-ender” was another attempt at building a “pusher” configuration fighter. This one was unique in that it also had a swept wing and a canard (elevator in front). Pretty advanced stuff for 1943.
Unfortunately the XP-55 suffered from poor handling and two of the three prototypes were lost to accidents. Like many of these oddball designs, it looked good on paper but never really performed as well as expected. In fact, more conventional fighters were able to outperform the XP-55.
By 1945 jets were on their way and the Army saw no reason to press on with the XP-55.
Northrop XP-56 Black Bullet
Another of Jack Northrop’s wonderful tailless designs, the Black Bullet (great name!) was probably too far ahead of its time.
Like his other flying wings, the XP-56 suffered from stability problems. Today a computerized flight controls could make it fly straight but that wasn’t an option in the 1940s.
Like the XP-55, it was never ready in time before jets came along and made it pointless.
Vultee XP-54 Swoose Goose
Swoose Goose? Who named these things? I guess it does kind of look like a goose.
I really like the looks of this plane. It was quite advanced for the time, featuring a pressurized cockpit and a downward ejection seat, which I suppose was better than trying to bail out into a spinning prop.
The nose section could also pivot up or down (+3/-6 degrees) to assist in aiming the guns.
The XP-54 ultimately never flew as good as it looked, partly due to being much heavier than initially designed. They never could find the right engine for it either. The project was cancelled after only two prototypes were built.
Douglas XB-42 Mixmaster
I love this plane both for the name and the sheer weirdness of it. Sometimes weird actually does work. That was the case with the XB-42.
Two Allison V-12 engines drove a pair of contra-rotating propellors mounted in the back. This actually gave it better performance than the de Havilland Mosquito with twice the bomb load (sorry Brits). Plus it would have carried defensive armament that the Mosquito never had.
I also like the twin cockpits for the pilot and copilot. “OK pal, just stay over on your side and we’ll get along fine.”
While promising, by the time the XB-42 was in testing, jets were already on their way. There was no reason to continue development of a piston engine bomber.
Fisher P-75 Eagle
Just the fact that it was designed by General Motors (Fisher Body Division) would be enough to make the P-75 unique. It didn’t stop there, however. It was designed around the most powerful engine we had at the time. Two Allison V-12 engines were joined at the hip in a “W” configuration to make a 24 cylinder engine with 2,600 horsepower.
That was quite a lot of power for the day. For perspective: the legendary Rolls Royce Merlin, which powered the Mustang and Spitfire, “only” had 1,500 or so horsepower.
The engine was mounted behind the pilot, similar to the P-39 Airacobra, and drove a pair of contra-rotating propeller through a driveshaft.
Since GM didn’t have much experience designing aircraft, the P-75 was cobbled together from an SBD Dauntless tail, a P-40’s outer wings, and F4U Corsair landing gear. Surprising it flew at all, but it actually flew pretty well.
So why wasn’t it ever produced? This was yet another case of an aircraft no longer being needed by the time it reached production.
The initial requirement was for an interceptor with tremendous rate of climb. By the time the first prototype flew in 1943, the Army needed a long range fighter more than it needed an interceptor.
By the time the P-75 could be converted to a long-range fighter, it was 1944 and we already had long-range fighters like the P-51 Mustang. The P-75 wasn’t much of an improvement over the P-51 or P-38 and it was decided to concentrate on building the designs we already had.
With a total of thirteen built, the P-75 entered the ranks of great aviation might-have-beens.
Mikoyan-Gurevich I-250 and Sukhoi SU-5
The Russians did not have a practical jet engine in the mid 1940s but they needed something to counter the German jet aircraft that were on their way. One attempt to solve this problem was through the use of “mixed propulsion”.
Both Sukhoi and Mikoyan-Gurevich developed similar fighters using an odd engine called a “motorjet”. Think of it has a standard piston-engine WWII fighter with half of a jet engine stuck in the tail. Unlike a normal turbojet, the compressor of the motorjet was driven by the piston engine via a driveshaft and clutch arrangement. It was almost like having an afterburner of sorts.
The setup worked, to a point. When engaged, the motorjet gave 50 knots of extra speed, but could only be run for 5-10 minutes due to overheating. The rest of the time it had to be carried around as dead weight.
Keep in mind that no matter how much thrust you put behind a WWII fighter, it’s only going to go so fast due to the limits of its aerodynamics. You’ll either be limited by drag or you’ll start ripping parts off (bad).
Like many of these interim designs, by the time they got the bugs worked out of it the problems with jet propulsion had been solved. Both designs were discontinued in favor of pure jet aircraft.
Bereznyak-Isayev BI-1
While behind the West in the development of jet engines, the Russians were leaders in the field of rocketry. It makes perfect sense that they would try to build a rocket powered fighter.
The “Devil’s Broomstick” as it was sometimes called flew 12 times on rocket power.
A version was built with a ramjet engine mounted on each wingtip in addition to the rocket. A ramjet is a simplistic jet engine that requires a certain amount of forward speed before it will even run. As such they’re mostly used on missiles. This could have been an attempt to solve the very short endurance of the rocket engine. To my knowledge this version was tested in the wind tunnel but never flew.
The BI-1 performed beautifully but was marred by problems. The highly acidic fuel was dangerous both to the pilot and to the aircraft itself. The effects of transonic flight were not fully understood at this time and one prototype crashed at high speed. This was most likely due to shock waves forming on the control surfaces.
Once again, no matter how much thrust you have, your top speed is limited by aerodynamics. Even with rocket power the straight-winged BI-1 would only go so fast.
Since rocket powered aircraft have always suffered from very limited endurance, the BI-1 was discontinued as soon as jet aircraft became feasible.
Messerschmitt Me 163 Komet
Tricky to fly? Check.
Only seven minutes of fuel? Check.
No landing gear to speak of? Check.
Dangerous to land? Check.
Highly corrosive fuel? Check.
Likes to explode? Check.
The rocket-powered Komet had incredible performance for its day. Its speed and rate of climb were unmatched until the Bell X-1 flew in 1947.
The Komet took off on a wheeled dolly, which was dropped as soon as it became airborne. It then climbed very quickly to around 39,000 feet. A typical attack profile was to climb through an Allied bomber formation and then dive back through it before gliding back to land. It would then attempt to land on wooden skid under the belly.
The Komet proved a difficult target for Allied fighter pilots. It was too fast to catch when under rocket and also highly agile even when gliding.
Fortunately for the Allies it was just as dangerous to the Germans. For every Allied bomber shot down by a Komet, roughly one Komet was lost to an accident.
Legendary test pilot Eric Brown made an unauthorized powered flight in one after the war and described the experience:
The noise it made was absolutely thunderous, and it was like being in charge of a runaway train; everything changed so rapidly and I really had to have my wits about me. I had been used to the top fighters in the game with rates of climb of about 3,000 feet per minute, but this thing climbed at 16,000 feet per minute.
The angle of climb was about 45 degrees and I couldn’t see the horizon. It was an incredibly volatile aircraft, and its operational record – just 16* kills and 10 aircraft lost in combat – made it, in my opinion, a tool of desperation.
*The Germans claimed 16 kills, the Allies only confirmed 9. This sort of thing was (and still is) common in air combat.
Dornier Do 335 Pfeil
Another late-war German “wonder weapon”, the Do 335 had two engines in a unique push-pull or “suck and blow” configuration.
Getting out one would have been tricky with that Quisinart blade spinning back there. Fortunately it had one of the first ejection seats plus a system to jettison the rear propeller and vertical fin prior to ejecting.
The Pfeil or "Arrow" was quite fast for a piston engine aircraft and reportedly flew quite well. It just came too late in the war to do anything. One managed to outrun a flight a Hawker Tempests at low altitude. Quite impressive since the Tempest was one of the faster Allied fighters of the war.
Only a handful of these were built before the US Army overran the factory in 1945. The ultimate air-superiority weapon being an enemy tank parked in front of your hangar.
Today only one exists. You can see it at the National Air and Space Museum at Dulles Airport.
Heinkel He 177
You may not realize it but the Luftwaffe did have a 4-engine heavy bomber in World War II. This was the highly advanced, perhaps too advanced, Heinkel He 177.
I think this aircraft was a case of German designers being just a little too clever for their own good. In order to reduce drag, the He 177 was a 4-engine bomber with only two propellers. Each nacelle contained two Daimler V12 engines “joined at the hip” and driving a single large propeller through a shared gearbox.
Sounds simple enough but the devil is in the details. The Daimler “power system”, as it was called, was both difficult to work on and prone to overheating and fires. Fires were so command that the plane was nicknamed the “Luftwaffe’s Lighter” or the “Flaming Coffin”.
In the words of the commander of the Luftwaffe’s test facilities:
“Why has this silly engine suddenly turned up, which is so idiotically welded together? They told me then, there would be two engines connected behind each other, and suddenly there appears this misbegotten monster of welded-together engines one cannot get at!"
The He 177 had excellent performance, when it worked, and roughly 1,600 of them saw operational service. Control forces were reportedly very light for such a large aircraft. When Eric Brown tested a captured He 177 he found the elevator forces in fact to be much too light. This may have been what caused several He 177s to break up in flight. He summed the aircraft up in one sentence:
"one of the very few German aircraft of the period that I tested that I did not enjoy flying"
Mistel
Mistel (Missletoe) was a German “Frankenplane” used late in the war. It consisted of a fighter, usually an FW-190, mated to an unmanned bomber that had been converted to a giant bomb. The single pilot would aim this whole contraption at the intended target and then send the flying bomb on its merry way. Usually the target was something big, like a bridge or dam, because the bomb had no guidance.
Roughly 250 of these were used during the war with limited success. While a very interesting idea it had little impact on the war.
He-111Z Zwilling
What do you do when your massive cargo glider is too big for any single plane to tow it? If you’re the Germans you join two of your He-111 bombers together and then slap an extra engine on for good measure.
When the massive Me-321 cargo glider was built, it was towed by no less than three Bf-110 fighters. This proved dangerous to say the least.
Since no existing plane in the Luftwaffe inventory could tow the “Gigant” (Giant) the He-111Z was created. It looked plenty weird but it apparently worked well enough.
There were plans for a long-range bomber version, but Germany was on the defensive by then and bombers weren’t a high priority.
A total of 19 were constructed. Most were shot down or destroyed on the ground. The four survivors were unfortunately scrapped. I would have loved to have seen one of these in a museum.
Bachem Ba 349 Natter
The Natter (Adder or Viper) was essentially a manned surface-to-air missile.
The rocket powered craft would be guided by its autopilot to intercept a bomber formation. The pilot would take over for the final intercept and fire a salvo of 28 nose-mounted rockets into the Allied bombers.
There was no way to land the Natter. It was a one-time good deal.
It was not, however, a suicide craft as has sometimes been suggested.
After completing his mission, the pilot would then separate the nose section and cockpit from the rest of the aircraft. Once the cockpit was slowed down to a safe speed, he would then bail out.
Like the ME-163, the Natter would take off on a wheeled dolly, which was cut loose as soon as it became airborne. Launching the Natter vertically from a launch pad like a rocket was even tested. This would have eliminated the need for airfields, which were under heavy Allied attack by this time.
Unlike a lot crazy German late-war designs, I think this one might have actually worked. The war ended before it could be put to operational use. Once again it would have been too little too late, but might have given us a nasty surprise.
Kyūshū J7W1 Shinden
The Japanese produced some interesting designs at the very end of WWII. The Shinden (Lightning) was meant as an interceptor to counter the B-29 raids.
Similar in configuration to the XP-55 Ascender, the Shinden was set up in a pusher configuration with a swept wing and canard. Getting enough airflow to cool the rear-mounted radial engine proved to be a problem but probably could have been solved given time.
Two prototypes flew before the end of the war. Some very grainy flight test footage exists on youtube.
Another example of “too little too late”. It’s doubtful the Japanese could have produced enough of these to change the outcome of the war.
Yokosuka MXY-7 Ohka
Let’s suppose you’ve developed a rocket powered anti-ship missile but you have no way of building a guidance system for it. What do you do?
Well, if you’re Japan in 1945 you just find some brave soul idiot who wants to die for the emperor and have him fly it to its target.
The Ohka (Cherry Blossom) was air launched from a G4M “Betty” bomber and damaged or sank seven American ships. The best defense against this weapon proved to be shooting down the bomber before it could get within the relatively short (23 mile) range of the Ohka. Easy enough since the Betty had a tendency to burn and was called the "type one lighter" by its crews.
There was a certain grim logic to this weapon. If a single person could take out an enemy ship, that’s a pretty good trade off. At the Battle of Midway we lost an entire torpedo squadron (VT-8) without them getting a single hit on a Japanese ship. It’s just that there’s a big difference between knowing you might die and knowing you will die.
The Germans looked at a similar weapon, using a converted V-1 ”buzz bomb” but they at least gave the pilot a parachute (even though using it would have been iffy). It’s easier to get someone to sign on if they think they at least have a chance of survival.