Japanese piston aeroplane of long range

I agree long range of Japanese a/c, especially the shocking (to the Allies) reach of landbased A6M’s early in the war, was mainly a matter of the relative weighting of design characteristics with approx the same technologies used in the West. Nothing was particularly revolutionary technically about the planes or technology in them, although the West had assumed it would be inferior and it wasn’t. Also the sort of long range flying techniques experimentation and training done in the USAAF in mid war, as mentioned for P-38’s, was done in the Japanese Naval Air Force *before* the war.

Before the Pacific War that is. One big institutional impetus toward long range design requirements and training in the JNAF was their experience in China. They, rather than the Japanese Army, had the main force of “heavy” (would later be considered mediums by WWII stds, Type 96 Land Attack Plane, ‘Nell’) bombers. They did well when escorted by their own fighters, which could dominate the intercepting Chinese (sometimes Soviet piloted) fighter opposition in general. But when unescorted raids were tried early on, or when the key Chinese political/strategic targets were withdrawn into the hinterlands outside the range of Japanese fighters from coastal Chinese airfields, those ops often proved costly. Drop tanks on their A5M’s (Type 96 Fighter, ‘Claude’ in WWII) were a partial solution, but even a small number of A6M1’s sent there for operational evaluation, in 1940, turned the whole situation around (in raids against Chongqing where the Nationalists had move their capital). IOW the Japanese Navy had already gone through some of the lessons the USAAF learned in Europe and Pacific about the key value of long range fighters in supporting bomber operations, prior to 1941.

Joe

Lean Burn

Years ago I read an excellent book called ZERO – worth a read as it was written by a Japanese Navy staff officer and gave a lot of insight into their thinking and operations.

No doubt there were brave pilots – one had two shells in his head and kept poking them to keep awake until he got back to base! Then he was back in the air a few weeks later…

Anyway, in the book there is constant reference to leaning off the mixture to get longer range. Doesn’t say how, but they must have had a cockpit control of some sort.

Bri:)

Expert:

Almost all of fighter aeroplne, which built aft Zero, such as Shiden Raiden etc also has long range with reasonable arm. and weapon. So I think there is some partial emphasis of their engine design, but I don’t know what…..

Engine design is an important factor – the Japanese by and large used radials, which like their American counterparts were very efficient at nominal cruising rates. These engines were designed for relatively slow cruising speeds with excellent fuel consumption and for short periods when actual combat required high power and high fuel consumption.

I recall reading some years ago that the American aviation engine manufacturers were concerned as much with designing engines for longer term economical civil use more than combat use. This was one of the philosophies that enabled them to corner civil airliner production at the expense of the European countries. I suspect also that greater internal civil domestic air route distances in continental America encouraged this practice, and this led to the development of excellent engines with excellent cruising potential.

Japanese engine design was influenced greatly by American practice and the potential for long civil passenger routes in Asia probably created a similar effect to that of American domestic airline practice. European air routes were relatively speaking much shorter, while only the British with their Imperial connections had a similar outlook and also developed very efficient radial engines. Unfortunately they rather lagged in airliner development.

But regardless of that, I think that despite, an apparent Japanese superiority in this area of long range economical usage of radials, the American radial engine designs were just as efficient. There were more factors at play than just engine range etc. Aircraft manoeverability in combat, weight of numbers and pilot experience were just as important in the first year of the Pacific War. Japanese superiority eroded swiftly once the more heavily armed American aircraft came to be flown by pilots who understood how to take advantage of their aircraft’s strengths.

To follow on to the subject, engine settings can make quite a difference in fuel usage.

A beutiful example of this is the P-38 in the Pacific theatre and Charles Lindbergh.

He visited the 475th Fighter Group as a technical advisor, and showed the Lightning pilots the low-RPM, lean fuel mixture technique he had used on his trans-atlantic flight. Despite the engine manufacturer’s “minimum cruising RPM” of 2,000 RPM, and the warnings that cruising at lower RPMs would damage the engines, he taught them to fly at 1,600 RPM… by adjusting the fuel mix & propellor blade angle settings and raising manifold pressure… and still prevent premature fuel detonation while maintaining airspeed.

This increased the range of the P-38 by over 20% without any physical modifications.

Apart from extra tankage – some Japanese long range aircraft for example the Mitsubishi A6M was of very light construction with minimal pilot protection and had a reasonably efficient and powerful engine, with low wing loading.

Those factors plus good aerodynamics enabled them to fly long range and fight when they reached the objective. Later aircraft which were built when the Japanese went on the defensive lost those capabilities as their role was changed, and increased armament and pilot protection became the chief priority.

That is a very short answer but it captures the basics. Others will probably expand on this.

Expert:

Almost all of fighter aeroplne, which built aft Zero, such as Shiden Raiden etc also has long range with reasonable arm. and weapon. So I think there is some partial emphasis of their engine design, but I don’t know what…..

Sakai 21…I think

Plus they had found a way of being able to cruise the aircraft at a very fuel effecient speed.Think it was high boost and low revolutions(rpm) but this is based on memory.It gave the allies a huge shock finding bombers being escorted by fighters hundreds of miles outside of known range.
Have heard a story,can,t comfirm it did or didn,t happen but a Japanese plane took off from East Timor,flew to Darwin,across to Sydney,up to Brisbane and back home without being intercepted sometime in 1943.One time being passed by Boomerangs without being touched…Anyone know the story???There is a photo of the Sydney Harbour Bridge taken from the air with a Hinaramu on the wing…apparently…..

Apart from extra tankage – some Japanese long range aircraft for example the Mitsubishi A6M was of very light construction with minimal pilot protection and had a reasonably efficient and powerful engine, with low wing loading.

Those factors plus good aerodynamics enabled them to fly long range and fight when they reached the objective. Later aircraft which were built when the Japanese went on the defensive lost those capabilities as their role was changed, and increased armament and pilot protection became the chief priority.

That is a very short answer but it captures the basics. Others will probably expand on this.