Aces High Bulletin Board

General Forums => Aircraft and Vehicles => Topic started by: lasersailor184 on March 24, 2004, 09:23:10 PM

Title: Shifting systems for airplanes?
Post by: lasersailor184 on March 24, 2004, 09:23:10 PM
I've been thinking about this recently.  Has anyone ever tried to put a gear system on an airplane?


Would it put out more power?
Title: Shifting systems for airplanes?
Post by: MrCoffee on March 24, 2004, 09:48:45 PM
Its automatic. Also refered to as the propeller reduction system normaly located at the bellhousing where the prop is.

http://www.powersportaviation.com/Home/Reduction%20drive/Reduction%20drive.htm

I believe that using gears to drive the prop to higher RPMs would create more torque/gyro affects. So the balance is found between RPM and prop design/angle.
Title: Re: Shifting systems for airplanes?
Post by: HoHun on March 24, 2004, 10:34:32 PM
Hi Lasersailor,

>I've been thinking about this recently.  Has anyone ever tried to put a gear system on an airplane?

Yes. The Dornier Do 14 flying boat built in 1933 had a large four-bladed pusher propeller on a pylon above the fuselage that was driven via shafts and gearing by two coupled engines in the fuselage.

When it was test-flown in 1936, it was found that the engines couldn't bring the fixed-pitch propeller up to speed at take-off. The solution was variable gearing with one speed for take-off and another one for cruise.

However, variable-pitch propellers made for a much quicker and better match between engine and propeller characteristics for any flight situation, and so the Do 14 was a technological dead end.

Regards,

Henning (HoHun)
Title: Shifting systems for airplanes?
Post by: Maverick on March 25, 2004, 12:41:57 PM
Even some "modern day" piston aircraft still use geared engines. They allow the engine to turn at higher RPM's and the gearing lowers prop speed to the most efficient range. These aircraft also have variable pitch (or constant speed) props on them as well. For any aircraft with a constant speed or variable prop,. RPM is not the direct  result of more or less power from the engine.
Title: Re: Shifting systems for airplanes?
Post by: _Schadenfreude_ on March 25, 2004, 12:48:40 PM
Quote
Originally posted by lasersailor184
I've been thinking about this recently.  Has anyone ever tried to put a gear system on an airplane?


Would it put out more power?


well in FB you have to change from stage 1 to stage 2 turbo charger as you go through 2500 meters...also can run your engine lean or rich, fiddle with the prop or leave it on auto.....

nice trick is to run yr engine on rich at alt if you attacked then spin down to the ground - your leave a trail of smoke and yr attacker thinks you're dead and doesn't follow you down...well sometimes he doesn't....

Complex engine management is way cool!!
Title: Shifting systems for airplanes?
Post by: lasersailor184 on March 25, 2004, 01:49:17 PM
So the RPM like the RPM in AH tell you which gear or power you're at?
Title: Re: Re: Shifting systems for airplanes?
Post by: Red Tail 444 on March 25, 2004, 02:31:52 PM
Quote
Originally posted by _Schadenfreude_
well in FB you have to change from stage 1 to stage 2 turbo charger as you go through 2500 meters...also can run your engine lean or rich, fiddle with the prop or leave it on auto.....

nice trick is to run yr engine on rich at alt if you attacked then spin down to the ground - your leave a trail of smoke and yr attacker thinks you're dead and doesn't follow you down...well sometimes he doesn't....

Complex engine management is way cool!!


There was a similar tactic in the LW rides...or correct me if I am wrong, but I heard from a 38 pilot..and also another buff gunner, that diesel engines smoke when inverted, and the LW guys would use that to escale, or to sucker the pilot / gunners into thinking the plane was damaged...

anyone else hear of this?