Early Monoplanes

[ohogain]

During the interwar years (specifically, 1919-1930), the US, Italy and UK concentrated on biplanes for its fighters, while other countries, like France and Poland, either concentrated on monoplanes (Poland) or a mix of biplanes and monoplanes (France).

I have a multi-part question.

The tradeoff between the monoplanes and biplanes, as I understand it, was speed for the monoplanes vs maneuverability for the biplanes.

Why the difference in choices between the different countries? I read that the UK had a bias against monoplanes going back to 1912, but why did Poland and France emphasize monoplanes?

Why did France Poland concentrate on parasol-winged monoplanes rather than low-winged monoplanes?

 

[GrauGeist]

The interward period was much like the post WWII period in regards to the advancements in flight technology.

Biplane technology was reaching it's peak during the interwar period, where the technology was getting the best performance possible and yet, some nations were trying to advance one step further. You'll see the same thing in the last years of WWII and soon afterward, with piston technology being over-taken by Jet technology.

The U.S. was also working with monoplane aircraft, resulting in such designs as the Boeing P-26 and Martin B-10 by the early part of the 1930's.

 

[pbehn]

I think much of the development was governed by engine development and materials development. Bi planes and tri planes have more drag but are more manouverable and climb better. All nations eventually fixed on single engine low wing stressed skin monoplanes but for that you need engines approaching 1000HP. There was a debate between the wars between the mono and Bi plane, many still thought the manouverability of a Biplane was of paramount importance in air combat.

 

[Balljoint]

I suspect it had to do also with structural strength. While the biplane transferred the same lift for similar weight, the wings were attached to the fuselage at through two distinct structure and the wings mutually braced each other. The monoplane has only spars with little depth to transfer force from the cantilevered wing. It's a compromise between structure and drag. Of course the availability of higher power augured in favor of lower drag.

 

[Shortround6]

I think Balljoint has something. When dealing with low powered engines keeping the structural weight low was a prime consideration. So you had an argument/conflict between weight and drag. You also had evolving materials (see the thread on aluminium in airplanes) and it took until the late 20s for an all metal structure (not including covering) to become common.

The parasol fighter was thought to have advantages in pilot view, he could look over or under the swing with a tilt of the head, a broad wing several feet below the head was impossible to see around. They were also still working on stability in aircraft and stall/spin characteristics and the parasol wing was thought to have some advantages.

to understand a bit of the confusion going on at the time look at the commercial Lockheeds.

Low wing, high wing and parasol wing all using pretty much the same fuselage and wing depending on what the customer wanted/believed.

Retracting landing gear was a lot easier with the low wing

 

[bobbysocks]

i think a lot had to do with the glues for joints, material for covering, engine power ( including fuel octane), metallurgy and other technologies...the old engines were heavy for the hp they put out iirc....same with the old coverings. it is amazing what you can build now.

 

[ohogain]

Retracting landing gear was a lot easier with the low wing

That's a given. The only high/parasol winged fighters with retractable gear that I know of had the gear retract into the fuselage.