Re: planes and stuff

Guy Fawcett (
Mon, 05 Dec 1994 09:47:30 -0600 (MDT)

>As for stability of WW I type airplanes, Yes some were very
>stable while some were not. I am not an expert on the subject but I >do
recall in my reading that some like the sopwith camel were a real
>handful. These airplanes that were rotary engine powered had very >short nose
moments due the heavy weight of the engines plus that >heavy weight rotating at
2000 rpm or so certainly had a tremendous >gyroscopic effect as well.

The gyroscopic force of the rotary engine tended to make the nose rise during a
right hand turn and fall during a left hand. (somebody correct me if I got
this backwards). The Camel because of its particular moments was particularly
effected by this problem and a lot of low time time pilots spun their aircraft
in at low speed during landing and takeoff with sudden bursts of power that
caught them unawares and brougt the nose up. But not all rotary powered
aircraft were as badly effected due to their design and alot of pilots consider
the Sopwith Pup to be one of the best handling aircraft to come out of WWI.

>You also have to remember that in the sopwith camel there was
>no throttle control, it was either running full or not at all. You may
>recall hearing in some movies that feature WW I aircraft the sound of
>the engines, the brrrpp brrrpp sound. Apparently the pilot had to
>switch the ignition switch on and off in order to get a somewhat
>controlled application of power for taxi, takeoff and landing.

What the planes had was a power on setting with a mixture control which
provided some semblance of throttle but the idle setting on the mixture control
was such that the aircraft could not decend quickly enough for proper landing
so the pilot was provided with an ignition kill switch which allowed him to
blip the electrical power to the spark plugs and in effect shut down the
engine. By utililize the rotating mass of the engine as a fly wheel as soon as
power was restored the engine came to life again. Disadvantages to this system
where legion. If the blip was held down to long starting the engine again
could result in fire (the motor still was drawing fuel and expelling raw fuel
out the exhausts) or the engine may not start up (flooded) or the engine would
start up with a huge burst of power capable of turning the plane up side down
(torque roll). As you can see all of this would be hard to cope with if you
had just arrived at the front with less then 20 hours flight time most of that
spent in an Avro 504 with long wings and more inherent stability.

> I would guess that a R/C scale version of some of the WW I >airplanes would
tend to be as somewhat unstable as their full size >counterparts, not
impossible to fly but certainly requiring extra care.

Having flown a 1/5 scale Bristol (96") a 1/6 Scale Jenny a 1/4 Scale Nueiport
17 and a 1/4 Scale Fokker D VIII, I find the models of the rotary powered
aircraft to be the most interesting to fly and the hardest to takeoff and land

>Interesting what you say about the Sopwith Camels, and their whirling
engines. Has anyone tried building a rotary for a model, and then flying

Several working rotaries have been made by dedicated modellers but I haven't
heard of them being flown in a model but that's bound to happen if I get a
flight report on one I'll pass it on :-).

>And yes I did notice the brrrpp brrrpp sound. In fact I have just now
>been watching the old classic "Dawn Patrol" with Erroll Flynn and >John Niven
and was wondering about that very brrrpp brrrpp sound. >The planes did look
like camels, dispite the fact that the story was >set in 1915, before the
camels came on the scene.

Never trust movies for historical accuracy. In the movie "Richthofen and
Brown" they would have you believe that the Fokker DVII came before the Fokker

Sorry if my answer is a little long winded and hope it was of some interest.

Tally Ho