Author Topic: Combat trim  (Read 449 times)

Offline jhookt

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Combat trim
« on: March 02, 2007, 09:17:15 AM »
i have always assumed the intent of combat trim is used to mantain level flight. is this true? would using manual trim in a dog fight give me a slightly better edge over the opposing aircraft? typically i only use manual trim to pull out of a compressed dive, but are there other advantages?

Offline bozon

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Combat trim
« Reply #1 on: March 02, 2007, 10:16:52 AM »
Technically CT doesn't give you any advantage. In practice it makes a difference in how YOU handle the plane. In some particular planes (P38, mossie) CT can put you in trouble.

What you have to realize is that CT constantly adjusts your trim to a theoretical level flight at your given speed. If you are in a turn fight and loose speed the CT will continue to trim nose-up thus causing the same effect as you pulling harder on the stick - even though you hold it still. I find it makes me blow away more energy than I want to.

If you stall out the plane, due to the loss of speed, CT will trim you full-up making it harder to regain control, especially if you start to spin. In the Mosquito, due to what appears to be a bug in center of gravity, it is almost impossible you get out of a spin or deep stall when the CT is on - you just can't get the nose down and gain forward speed.

The other problem is high speed dive. CT will continually trim you nose-down making it harder to pull out of the dive.

Some people leave it on and are aware of when to turn it off and correct manually. I leave it default off, and turn it on for a few seconds to get close to trim, then turn it back off. Fine time I do manually.
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the almost incomplete and not entirely inaccurate guide to the AH Mosquito.
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Offline Bronk

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Combat trim
« Reply #2 on: March 02, 2007, 11:48:16 AM »
Note on combat trim in the 38.
When  it's off, I have yet to enter an uncontrolled compression state.

Only time it happens now is when I forget to turn it off before an extended dive.

Bronk
« Last Edit: March 02, 2007, 12:19:39 PM by Bronk »
See Rule #4

Offline uberhun

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Combat trim
« Reply #3 on: March 02, 2007, 12:11:26 PM »
I use it sparingly to trim out plane just before I shoot. It seems to give me less nose bounce.

Offline Murdr

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Re: Combat trim
« Reply #4 on: March 02, 2007, 03:35:37 PM »
Quote
Originally posted by jhookt
i have always assumed the intent of combat trim is used to mantain level flight. is this true?
More accurately you likely mean to say"to have a neutral nose (no pitch, roll, or yaw) in the absence of stick pressure."

As to the rest of the question, bozon already answered with the same points I would make.

Offline mecrazy

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Combat trim
« Reply #5 on: March 02, 2007, 04:48:23 PM »
hey umm my stick will not work wit rudders:furious