trim, trim trim (grrrrrrrr!)

[terracota]

Can someone please tell me how I use the trim keys?
I use x (trim level)to autolevel (just to fligth level. other use?)
I use toejam+x (autoangle) =forget it I never use it (what this one is good for?

I use alt+x (auto speed)just after take of and grab altitud, until I'm very high  them I never use it

ok I ask this because I dont find any other use of that keys I now there are more things
i.e to climb? dive? I hear that some planes required a lot of trim why? when I should trim? this planes are just for experts becasue the trim things?
E friendly?

any other trims that I dont now what they do (sorry I now what they do but dont now why  )
elevator trims? no idea
rudder trims ? who nows waht this one is good for?(I just use A,S,D here to left , center, etc.)

some tips to use it please?  or any lnk to a document explaining this ?

[humble]

ok...x shift sis the most valuable to me...it stabilizes you in your current orientation...great if you get a mid combat breather or are zooming..diving wtc.

As for trim in combat...elevator and rudder mostly...trim a little up elevator as you turn and watch your "ball" trim rudder as needed to avoid skidding. aerlion trim is tougher for me...i'm still not certain its worth messing with unless your way out of wack.

[Lephturn]

Ok.. I haven't updated this site in ages but...

I have an article here on Auto Trim and some examples of how to use it.
 http://users.andara.com/~sconrad/trim.htm

Check it out.

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Lephturn - Chief Trainer
A member of The Flying Pigs  http://www.flyingpigs.com


"My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
 - Steve Earl

[terracota]

great help thank's  

[Lizard3]

   I always use shift x for auto climb. Pull your nose up to an appropriate angle then set shiftx. I've never used the auto speed trim thingy and can't figure out why I would need to. (?anyone?)
  You also will need to do a bit of manual trimming. The I and k keys will trim elevator. I use these on jabo and B&Z runs. Say your (auto)level and at best speed, you arrive over the enemy base, invert, pull back and go screaming in. If you don't manually trim the elevators, you will end up fighting your stick/aircraft for control. More speed(in the dive)= more lift(up vector)and you can't keep the nose pointed where ya want it. I trim elevators down past mid point whenever im going diving down. This also will apply somewhat to the rudder(J and L) and eileron(M and ,)trim. Whenever going from "slow"(climbing) or "at good speed"(running level) to "I'm going so fast my cheeks are flapping in the wind"(any sustained dive) I try to trim the eilerons and rudder to center.
   I hope this helps.

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Lizard

"Engage the enemy; not the keyboard"
Hangtime

[Tac]

Well, the I and K trim keys I find very usefull.

I remapped them to R and F so they are closer to my rudder keys though  

When diving, trim it low, so you wont have the plane fighting you as you dive, during combat I find that in my 38, if I trim it all the way up during a loop, my plane flips a lot faster... at low speed fights when you got those flaps full out, putting the trim below the middle will give you a few more secs of manouvering before that buzzer starts screaming the horrible death you're getting yourself into...

All this is in P-38 though.

Hope this helps.

Cheers

[Lephturn]

Lizard3,

Auto-Speed trim is the best way to climb because it will keep your aircraft at it's best climb speed.  If  you use auto-angle to do a climb, you will either not climb as fast as possible, or you will pick too great an angle and your plane will stall.

I use Auto-Speed for climb-out and to trim my plane to a specific speed before I engage.  I use Auto-Trim Angle to keep my plane in trim as I accellerate in a dive or decellerate in a zoom.

Check out the article I mentioned above for more details and a better example.  



------------------
Lephturn - Chief Trainer
A member of The Flying Pigs  http://www.flyingpigs.com


"My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
 - Steve Earl

[Andy Bush]

Here's one for the FWIW category...

When it comes to A2A or A2G maneuvers in the real world, the only time trim is ever mentioned is in the A2G technique of trimming the aircraft to weapons release airspeed prior to beginning the dive.

This has nothing to do with delivery accuracy. It is only a technique to reduce pilot workload...the workload in this case being the need to hold a specific release G while aiming at the target. Level deliveries are done at one G...all dive deliveries are done at something less than one G.

Trim has little to no effect on A2A maneuvers. In fact, in USAF pilot training, student pilots are taught not to trim when doing the majority of the aerobatic maneuvers. In follow-on fighter training, new pilots are taught not to use trim in BFM maneuvers...the speed changes are often too rapid to allow a pilot to trim off the stick pressures...and attempting to do so would only take concentration away from the real task at hand, killing the bandit.

Andy

[humble]

Andy,

Here it does seem that an aircraft in trim will out corner/out E one that is not...especially in the slower stages of A T&B end game. I don't know if this is in fact true but it sure seems that way to me. Is this specific to flight sims...or does an out of trim plane bleed E faster in real world as well?

[RangerBob]

The difference here in a flight sim is that we have  Auto Trim  and Programmable Trim Hat Settings on our joysticks or keyboards as compared to real combat flying.

In WWII a fighter pilot could not afford to take his attention off of the fight for even a few seconds to fool with the manual trim settings while in combat. Here in Aces High all we have to do is hit either an auto trim in a dive, or hit a hat button to trim up down right left etc. We can easily do this and still keep our attention, and eyes, on the target. As a result we flight sim pilots use trim controls when a real pilot wouldn't even consider it.

Ranger Bob

[Andy Bush]

Humble

I'm not an aero major, and when we get down to this level of detail, I don't have the depth of book learnin' to be an authority!

Earlier posts referred to 'trim drag'. In aero theory, trim drag is not what the posters seemed to think it is. It is not drag caused by being 'out of trim'. Instead, it is the induced drag of the horizontal stabilizer/elevator combo as they produce a force (lift) to balance the aircraft along its longitudinal axis.

As I have tried to say earlier, pilot trim is intended to relieve stick and rudder forces...it's a workload issue, not a drag issue.

Is AH correct in modeling trim as a function of energy conservation? I don't know. My last co-pilot was an aero major, and I asked him about it. He thought that in airplanes with trim tabs on the elevators that the total induced drag of the horizontal tail would be greater in a fully trimmed condition...he thought that an untrimmed elevator trim tab would produce little to no extra drag.

Here's how I see it. If we fly at a certain speed and a certain G load, the tail has to produce a specific amount of downforce lift to keep the aircraft at the required angle of attack. To do that, the tail will be deflected from its neutral position. To my understanding, the position that the tail is in to produce the required downforce is the same regardless of its trim condition. The trim controls are there only to help the pilot hold the stick in the desired position. In other words, when untrimmed, it may take 20# of stick force to hold the nose up...and when completely trimmed, it takes no stick force to hold the same attitude. The tail is in the same position in either case.

I see this issue as an 'apples and oranges' thing...meaning folks are talking turn performance and the item in question (trim) is intended to reduce pilot workload.

I do see a possibility that a pilot who has not trimmed can fly less efficiently that his 'trimmed' counterpart...but that would only be the result of the 'untrimmed' pilot not being able to hold the exact G needed for max performance. He may well be inadvertantly changing his G load (back stick position) from too much G to too little as he maneuvers. This would probably result in poorer turn performance and energy conservation.

In any case, I think the difference is so small that other BFM and tactics factors more than override it in importance.

Andy  

[Sorrow[S=A]]

Respectfully andy- I have to disagree. Almost every account I have read about WWII fighter combat planes indicate trim was very important in them to maximize performance. Mostly this was simply elevator trim or rudder trim. Some only had one or two trimmable surfaces. But for example- in a 109 where the amount of force on the stick could seriously affect how hard you could pull it, trimming it properly would be very important.

OTOH from what I read there was nowhere near the trim buttons we have in AH. Most had one or two trim wheels easily accesible beside the throttle hand. The 190 however was most fearsome as an opponent because both elevator and aileron trim were trimmed at the same time with one wheel- less work meant more attention on a bandit and every report on the plane notes this.

[Andy Bush]

Uncle...I give!!

Here is a picture of the Me-109 horizontal stabilizer trim markings. When the pilot turned the elevator trim wheel, the leading edge of the stabilizer moved up and down thru the range shown.

Nose 'up' trim would move the stabilizer edge down.

 

[Vati66]

Thanks guys!  I just learned alot by reading this thread


Vati

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Good luck and Good hunting

[terracota]

well very good , now Im totally lost  
should I use it or not?
I dont understand how can u use trim in a dive
if I need to point my nose to the enemy or his fligth path in a dive and my plane is trimed, so I dont touch the joystick? because if I dive trimed and the enemy changes direction I should follow him with my joy and the autotrim key now is off, becasue
I readed that when u trimed and move joy the auto trim is off, so whats the point?