Aces High Bulletin Board

General Forums => Aircraft and Vehicles => Topic started by: agent 009 on April 30, 2005, 11:22:17 PM

Title: Tail trimming
Post by: agent 009 on April 30, 2005, 11:22:17 PM
Tail trimming devices, can someone elaborate on different versions of these? 190 had a tail trimming device to tighten turn. Also how does bike chain work in 109 & 190?

What did allied planes have in this regard?
Title: Tail trimming
Post by: Tails on May 01, 2005, 12:11:42 AM
If your talking about your average trim device, they came in three flavors.

One variety uses a smaller movable surface attached to the main control surface, that used aerodynamic forces to move the control surface. Trim tabs are the most common form, although some aircraft (Piper products for example) use a moving surface that lines the rear of the main control surface.

The next version is what most airliners, and the Bf-109, had, and that is a full moving stabilizer. When you trim the aircraft, the whole stabilizer moves, simple enough really.

The least common actuates the control surfaces themselves. I cant off the top of my head give you an example of an aircraft that uses it, but when I took my airframes written test, that was a question.
Title: Tail trimming
Post by: agent 009 on May 01, 2005, 12:22:00 AM
Cool, here's quote bout 190 device.


'During dogfights between Fw 190s and RAF fighters it was not uncommon for the Luftwaffe aircraft to flick on their backs from a very tight turn and crash at full throttle. The cause of this disastrous behaviour was the pilot making excessive use of the electric tail-trimmer, an ingenious invention of Focke-Wulf, in an attempt to tighten an already very high 'g' turn, the aircraft eventually entering a high-speed stall from which there was no recovery.' German Aircraft of the Second World War - J. R. Smith and Antony Kay. Putnam, London 1972

& a neat site

Horizontal Stabilizer - Elevator  
At the rear of the fuselage of most aircraft one finds a horizontal stabilizer and an elevator. The stabilizer is a fixed wing section whose job is to provide stability for the aircraft, to keep it flying straight.http://www.lerc.nasa.gov/WWW/K-12/airplane/elv.html - 9k - Cached - More from this site
Title: Tail trimming
Post by: Simaril on May 01, 2005, 09:37:30 AM
Foxy, love your sig!!

:aok
Title: Tail trimming
Post by: Tails on May 01, 2005, 04:58:55 PM
Thanks Simaril :D

And to 009:

That sounds like pilots using the trim system to get a few more degrees of deflection out of the elevators. And the behaviour from that quote, sounds like a snap-roll resulting from too much deflection of said elevators.
Title: Tail trimming
Post by: Casca on May 01, 2005, 06:24:58 PM
Quote
Originally posted by Tails

The least common actuates the control surfaces themselves. I cant off the top of my head give you an example of an aircraft that uses it, but when I took my airframes written test, that was a question.


Prewar Luscombe 8A, Schweizer 232 or 233 gliders.  A spring or bungee assists in holding the control surface where you want it.
Title: Tail trimming
Post by: Tails on May 01, 2005, 11:07:30 PM
I was thinking about gliders when I typed that, but likes I said, specific examples escaped me. Thanks Casca!
Title: Tail trimming
Post by: Naudet on May 02, 2005, 04:44:06 AM
Quote
The next version is what most airliners, and the Bf-109, had, and that is a full moving stabilizer. When you trim the aircraft, the whole stabilizer moves, simple enough really.


Not only Bf109, FW190 had it also.
Title: Tail trimming
Post by: Tails on May 02, 2005, 11:20:49 AM
This just goes to show I am not as familiar with Tank's creations as I should be :D

This also explains why they were using the trim system to aid in elevator control.