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Kach22,

Pusher Prop Kyushu J7W1 Shinden

Interesting, but I can tell you at face value from an aircraft design perspective. Observe the photo of the Shinden..Notice anything..? Look and see that it has small wheels on the vertical stabilizers. This was an afterthought because of uncontrolled pitch nuances with the canard configuration. I say this because how high they are placed. This location and need tell me there are formidable pitch accelerations and habits with the controls 45 degree or so. The geometry and fitment of the wheels tells me as a designer it has a tendency to pitch wildly (up or down)! (reasonably educated guess) The canard is very small and placed forward farther than I would place it, just stating a "Moment" observation. I bet that bird was very frisky and not necessarily maneuverable. The pusher engine configuration really has no benefits other that the physical counterbalance for the cannard/CG. It looks revolutionary and probably better suited as a long range something..It could never fight anything we had after 1944. The test flight data revealed no great attributes..Thats why we didn't see more on the Battle field.

Aircraft in WWII had a common configuration that took 40 years to develop, even the ME-262 follow the same design parameters. Like the man said "Keep It Simple Stupid" (KISS) There is no better reflection of this than in nature.

Just my annoying .02 cents

Bob

Les,

Nice old photos! Did you work at the CAF?

Ever run into one of the founders, Lefty Gardner the P-38 owner? His stepson is a very good friend of mine and living in the Austin area flying for SWA.

How about this one?

Kawasaki Ki-61 Hien'Tony'
http://www.angelfire.com/fm/compass/K61.htm

Quote:

In early 1945 one of 275 engineless airframes was fitted with the Ha-112 radial engine. Although a sudden lash-up conversion this produced a staggeringly fine fighter, by far the best ever produced in Japan. This aircraft, designated the Ki-100, was put into production with desperate haste. One of the first Ki-100 units destroyed 14 F6F Hellcats over Okinawa in their first major encounter - without loss to themselves. The easily-flown and serviced Ki-100 fought supremely well against Allied fighters and B-29 bombers to the very end of hostilities in the Pacific.

http://www.vectorsite.net/avhien.html
http://www.vectorsite.net/avhien_1.jpg

Quote:

The Hien proved initially successful in combat against American fighters. As the war in the Pacific ground on, however, the Ki-61 found itself increasingly outclassed, but it soldiered on until the end of hostilities. This document provides a history and description of the Ki-61 and its radial-engine derivative, the Ki-100..............................By this time, the Hien was outclassed by American Mustangs and other late-model US fighters. In fact, when attacking B-29s Hiens often had to be protected by Ki-100s. Operations faded away as planes and pilots continued to fall in combat and fuel and spare parts dried up. By the end, the home defense units were no longer capable of posing a real threat to the Americans.

http://www.vectorsite.net/avhien_6.jpg

Guess not.........................................?

Quote:

Originally Posted by robert_snyder (Post 3439095)

The pusher engine configuration really has no benefits

Am I way off base to think of jet aircraft as "pusher"?

I mean the thrust is come off the rear in both cases.

The pushers eventually ruled the skys, we just don't recognise it.;)

Jet are 'pullers'.......at least that what the piston guys say...;)

Beyond that the real issue with pusher props is that they are less efficient... the prop has to deal with a disturbed airflow.. one that has already been 'used' by the wing....

'Tractor' props get clean air so the entire disc is working harder, hence its area can be reduced and the prop can have bigger blades with more bite( coarser pitch) ..none of these alone makes a big difference but together they add up..

In addition the basic configuration of the a/c to have a pusher prop was aerodynamically too advance for the technology of the time. It is basically an unstable airframe, made stable by oversizing the front surfaces to provide balance and control authority. However th is is only needed as the control systems of the time were unable to deal with an unstable aircraft, it had to be inherently stable to fly successfully. An unstable version would have add weight advantages with the accompanying performance benefits. Again incremental improvements that would have yielded better performance.

However the advent of the jet engine made efficiency improvements in aerodynamics slip down the list of priorities as speed improvements were needed to deal with all this new found power.

I think the best example of this is the Mustang and the Sea Fury. They both had highly efficient wings, which gave them such performance (and some speed reserves as witnessed by Reno Racers). Yet the efficiency of these aerofoils was not match until well into the third generation of jets.. we are looking to the century series. All because power was so plentiful and accessible.

I'm still searching for an answer to the 'best fighter (interceptor) question...The Bearcat does seems to be the winner, but the unknowns of the Yak 9 are bothering me....I wish they had flown together at Duxford or that somebody (Ray Hanna perhaps) had been able to fly both.. that insight would have been good.