Combat Trim & Dogfighting

[Someguy63]

I've heard that having auto combat trim enabled during a fight, can end up mis-positioning you, and can also mess up a shot that you have during that fight.

I've seen people mention that they have it off when in a fight, and I'm wondering what exactly this auto combat trim does and why people suggest turning it off while fighting?

 

[Wiley]

Combat trim sets your trims to keep you fairly close to in trim depending on the speed of your aircraft.  It assumes a clean airframe, no flaps or gear out, 100% throttle.  Varying any of those things will mean you will be further from trim.

I keep combat trim on most of the time when I'm cruising or BnZing.  When I remember to, I turn it off if I start getting into a turnfight, particularly if I've deployed flaps.  Having combat trim on with full flaps gives you a lot of nose high trim.  My basic rule of thumb is to turn it off when I drop below 180-200mph.

Wiley.

[Someguy63]

Combat trim sets your trims to keep you fairly close to in trim depending on the speed of your aircraft.  It assumes a clean airframe, no flaps or gear out, 100% throttle.  Varying any of those things will mean you will be further from trim.

I keep combat trim on most of the time when I'm cruising or BnZing.  When I remember to, I turn it off if I start getting into a turnfight, particularly if I've deployed flaps.  Having combat trim on with full flaps gives you a lot of nose high trim.  My basic rule of thumb is to turn it off when I drop below 180-200mph.

Wiley.

I've got it, thanks!

[deadstikmac]

This is a topic I am interested in as in my whole aces high career I have never turned combat trim off.

[Randy1]

Manual trim takes a bit of getting use too.  You have to find your trim set buttons or slider pretty quick sometimes if you get caught slow and need to pickup speed.  Sometimes I think combat trim has a bit of a damping effect.  Landing is sure easier with manual.

Delirium made note in his P-38 training class that in his opinion combat trim offered a more stable gun platform.

Bozon and I spoke of combat trim in a dive bomb attack.  He preferred manual an I CT.  I should not though CT can make it a little harder to make small adjustments in your attack.
At Bozon's suggestion I will switch back to manual trim dive bomb attacks.

I easiest plane to run manual trim on is the mustang.  I am sure there are others but the 51 comes to mind.

Interesting the P47 in WW2 testing was always noted as a hard plane to trim if I remember right.  IN AH it is no worse or better than the P-38.

My biggest problem with manual trim using a slider is resetting it for takeoff.

[Wiley]

This is a topic I am interested in as in my whole aces high career I have never turned combat trim off.

It doesn't make you fall out of the sky, and depending on your fighting style/plane choice it will have more or less of an effect on you.  I only started fiddling with turning it off the last few months as I noticed in the situations I described above it can affect how smooth a maneuver is.  It seems to me if I am making a hard turn with CT on, riding the blackout tunnel with the stick motionless, as I slow down it feels like the amount I'm pulling on the stick hitches slightly as the CT adjusts for the decreasing airspeed.  I can see the blackout tunnel hitch slightly without moving the stick.  Without CT on, that hitching goes away, and the pull is smoother. In the 'game of inches' of turnfighting, I find it helps a little bit, or it could all be in my head.

Best example of a plane that benefits from it is an F4U with flaps out.  With full flaps out, you've got to put in a buttload of forward stick to keep the nose level.  If you manually trim your nose down a few clicks to turn off CT, it's a lot easier to handle in the stall-150mph range.

If I'm doing anything other than stallfighting or landing, I keep my CT on.  If I'm landing, I get all my flaps out and gear down, kill the throttle, and autopilot on angle to get the plane flying true for whatever condition I'm intending on setting down in, and then move the stick to turn it off and land.

Wiley.

[bozon]

CT constantly trims your plane for level flight at full throttle regardless of what you are currently doing. Its only input is your current IAS.

In a dog fight the problem with CT is that it tends to make me bleed too much energy in a turn - If you hold the stick at a constant deflection, as your plane loses speed in the turn it keeps triming you nose-up, i.e. increase your angle of attack for the stick deflection that you are holding. For this reason I tend to keep it off most of the time.

In a dive, CT will keep triming you nose-down as speed builds up, making pull out ever more difficult. On planes like the 109, P-38, mosquito and some others it is almost a suicide device.

On the other hand, you generally do not want to be far off the "neutral" (i.e. level flight) trim. The compromise I adopted is to use the CT as a quick rough trimmer. When trim starts to bother me and I do not want to mess with the manual trims I turn it on for a second and immediately off again. I have it mapped to a button on my stick and go click-click when my speed changes and I feel "out of trim". In some planes the rudder needs a lot of trim input as speed varies (F6F for example, mosquito to a lesser degree). It is important to keep the slip/skid ball centered to conserved energy. Click-click, problem solved. I pulled some hard break turn and lost lots of speed, I find I keep constant back pressure on the stick - click-click, done. I am as close to trimmed as I need. For non-maneuvering flight, you have the auto-level, auto-angle and auto-speed (aka auto climb) trims.

One warning about turning CT on & off - do not do it while you are pulling Gs and in particular when the stall buzzer is buzzing. It will "jump" your trim instantaneously and you risk it pushing you beyond the stall and snapping the plane into a spin.

[Randy1]

I have had manual trim dump me into the water on a NOE below 50 feet when switching to and from auto level flight.  Not sure exactly sure how it happens but seems to happen when there is a large discrepancy between manual trim and auto level trim.

[Rich46yo]

I turn CT off when climb turning in a fight and manually trim up instead. I feel like this I fight the stick less, this is mostly with spits, K4s, KIs, LAs, P38s...ect All the fighters where it is in your interest to slow down and try to force your enemy to bleed off his energy in a climb fight. When I have him flattened out however, and have the advantage, I CT to shoot.

For some odd reason CT hurts my dive bombing. I will trim manual before starting the attack.

[ink]

I have always left CT on...

it does not make that big a difference.

stall limiter....YES turn that off.

[Scca]

I have always left CT on...

it does not make that big a difference.

stall limiter....YES turn that off.

I disagree...  CT makes a HUGE difference the slower you get. 

Try this one time, and get back to me.  Set a button to turn it on and off.  To do this you won't need to manually trim anything, just get an on off button set up. 

When you get into a combat situation, at 200, turn it off.  When you are turning and burning, especially when you nose up for a shot, you will find that with CT off, you will not be fighting so hard to get a shot.  The instability is worse when you add in flaps. 

I use to have the worst time in a hog, low slow, with flaps out trying to get guns on target.  I found out that CT was adjusting the trim, and my nose was going all over the place.  Now when I fly the hog, all I do is click off CT at 200, and don't turn it back on till I am out of a fight.

Try it, you may see a difference. 

[The Fugitive]

38s are great in the zoom. You can get under 100 coming over the top easily with control unless you have CT on. With it on and that slow the 38 almost gets stuck in the air. With it off I have no trouble kicking rudder and coming around on a guy.  Hit him with rounds as I dive back down,  or so much.

[TequilaChaser]

Hey Scca,
Some planes in AH having CT turned on and dogfighting and angles/turn fighting when slow under 200 ias or slower, it will not be as pronounced as it is in the F4U series ....

Some of the more forgiving aircraft in AH are the Zekes, most of the spitfires just to name some...

As you already are aware, using CT in the F4U series and flying slower than say 250~240 ias and you'll start experiencing stuff like nose bounce and nose popping upwards, each time you drop another notch of flaps.... Damn battery is dieing... Got to find my charger...

I'll come back to finish my post....

A quick note: I Seldomly if ever use CT ( combat trim ), I normally will get whatever plane I am in to regular straight level cruise speed flight ( usually somewhere from 270 ias thru 325/335 ias , depending on aircraft type ) then, I'll turn CT off ... Before I enter a dogfight...
This way, I help my self with more than just the nose bounce and flaps problems....

Will come back later, phone dieing...

<§>

TC

[morfiend]

 IMHO most newer players are best served with leaving CT on,it reduses pilot load and lets the player consentrate on the fight. Stall limiter should be turned off asap.

  While CT does have some issues,as it doesnt take flaps into account and tends to dial in full up elevator which can cause you to fight the nose up attitude,I still think most new players should leave it on until they are familar and comfortable enough to turn it off.

  I use CT about 90% of the time,there are only a few planes I turn it off for as a rule,38 comes to mind but I also have trim mapped to a couple of hatswitches which makes adjusting trim easy and I can override CT with a simple tap of a button,likewise I can turn it back on with another button.

  Most new players tend to fly either the spits or 51,while the 51 might benefit from using manual trim the spits will be even easier to fly if you leave CT on.


  It's pretty easy to tell players to turn it off,you dont need it but you must remember when you first started and how difficult it was to just keep your plane in the air once you learned to turn off stall limiter! Most players would be better off learning BFM long before turning off CT.


  YMMV.


   

[FLS]

Morf I'm sure you mean to say that combat trim dials in full up elevator trim  not full up elevator.