Aces High Bulletin Board
Help and Support Forums => Help and Training => Topic started by: terracota on July 12, 2000, 02:08:00 PM
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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 (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)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 (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif))
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 ?
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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.
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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 (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 (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"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
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great help thank's (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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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
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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 (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif)
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
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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. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Lephturn - Chief Trainer
A member of The Flying Pigs http://www.flyingpigs.com (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"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
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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
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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?
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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
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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
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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.
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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.
(http://www.doitnow.com/~alfakilo/109Trim.jpg)
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Thanks guys! I just learned alot by reading this thread
Vati
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Good luck and Good hunting
(http://home.earthlink.net/~spitfiremk9/eagle.gif)
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well very good , now Im totally lost (http://bbs.hitechcreations.com/smf/Smileys/default/frown.gif)
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? (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Terra--
Well, I am no super stick but the only time I really use trim to any effect is in a dive. As you know when your AC reaches high speeds the nose tends to pull up by trimming the elevater you can get the aspect of your AC corrected. In a Combat manuevering, I personally dont even try. I have in the past attempted, but to me it isn't worth the trouble.
hope this helps (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Andy,
hehe...surrender accepted (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)...seriously though, don't let us drive you totaly nut's.
All of us addicts are simply trying to understand our addiction. I do believe BFM has a major effect, but when you see someone in an equal E state and same plane pick up 180 degree's on you in 3 turns you do ask why.
Now, I'm the 1st to admit that some folks out think me, others outfly me and some do both (ouch). However, I've flown sims for close to 5 yrs now and am reasonably proficient in almost all area's. Now I'm parked in a T&B turn 15 ft off the deck, stall horn clacking,wep humming away working my yoyo's to correspond to the hills and valleys and watch a guy pull round on me in similiar circumstances...I'll ask HOW YOU DO THAT???...answer invariably is trim. Now you have to accept my judgement that we are co-e to start with. As an angles fighter I'm pretty good judging relative E state in end game. So I'm focusing on those "deadlocks" that occur...not midgame fights where you have an E vs angles situation still playing out.
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Never under-estimate the effect that flaps and fuel will have on a fight either. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
However some planes do seem very sensitive to trim. If you fly a 109, you better have those manual trim-keys handy, however a plane like the Jug is very tollerant of speed changes and requires very little trimming. These are historical strengths and weaknesses of the planes, so it has a place in the game IMHO.
One trick I use when I'm low furballing is to trim the plane WITH flaps if I plan to turn with flaps. Yep, if I plan to be crankin' and bankin' with a couple notches of flap, I'll trim the plane for that low speed with flaps popped. (Set flaps and use Auto Trim for Speed to the desired speed.) Then, I'll reel the flaps back in, speed up, and use manual trim to get "close" for ingress to the fight, and count the keystrokes. As the plane slows down, I pop flaps, and slowly feed that same number of opposite trim keystrokes back in so I'm in perfectly trimmed condition for a plane at say 160 with 2 notches of flap. (Whatever you trimmed for.) Also, try to do the initial set at the same altitude you will be fighting at, as this will make a difference.
Even if this doesn't gain you any efficiency (and I think it does), it DOES make it easier to control the plane. Easier to control means less flight surface deflection (less drag) and better gunnery. If you didn't plan to be turning slow with flaps, you need to use the manual trim keys to get "close". Get a feel for how much trim you need as your plane slows to stall speed, and then you can feed in something close during the fight and be in reasonably good shape.
In a close fight, being "in trim" can save your butt, even if it's just because you are steadier and don't miss that first shot.
Now, I rarely actually do this. I'd do it if I was heading into a 1v1 in same planes, or if I was low-alt furballing if I had time. Normally though, I'll just learn my plane so I know roughly how much trim she'll need with speed changes and flap changes. Once you know the plane, you can manually get it close enough to do the job.
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Lephturn - Chief Trainer
A member of The Flying Pigs http://www.flyingpigs.com (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"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
[This message has been edited by Lephturn (edited 07-17-2000).]
[This message has been edited by Lephturn (edited 07-17-2000).]
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Argghh!!
Jamaica me crazy!!
Go here and read a pilot report on the 109...pay particular attention to the info about high speed dives and trim.
http://hometown.aol.com/bf109gust (http://hometown.aol.com/bf109gust)
Once at the site, go to the 'Flying the Bf109' page.
Andy
[This message has been edited by Andy Bush (edited 07-17-2000).]
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Terra -
I'm a dweeb "bottom of the duelling ladder" newbie but I find the auto-trims help me a lot and I use the manual trims quite a bit also. I find it makes the aicraft MUCH easier to fly because you're not fighting it's desire to change attitude - I find the Spitfire and Mustangs particularly sensitive in pitch.
Examples:-
Before T/o I ALWAYS set my all my trims manually where I have worked out they need to be to make take off as easy as possible (for example in Spit 9 I set ailerons slightly left roll, rudder to 50% right and elevator full up).
After T/o at about 500ft I hit ALT X to climb out at best climb speed. Once established in the climb I look at how far I'm going and set the speed using the .speed xxx command to get the climb rate / groundspeed I want - for example if I'm away from the fight and only need about 15k then I'll set the speed in a Spit 9 to about 220kts which still gives a good rate of climb but means you have some manouvreing speed on if you get bounced. If on the other hand I'm grabbing as fast as possible I'll just leave it alone.
At the top of climb in cruise I'll hit X to auto level and then throttle back to conserve fuel. This gives me good time to scan for bogies.
Now diving for a fight I'll tend to engage ALT X and set a dive speed - say 350kts but I think I'll try SHIFT X after reading this thread. This means you arrive in the fight with the aircraft as easy to fly as possible for the first manouvre.
Obviously as you start to manouvre the speed will change and the trim state will change. The main axes to change causing problems will be pitch (elevator) and roll (ailerons) - again the Spit is mega sensitve in both. So I've found my solution is to map my trim keys for pitch and roll and rudder to the number pad and stick - 8=nose up, 2=nose down, 4=rudder left, 6=rudder right, button to left of hat on stick=roll left and button to right of hat=roll right (stick is Saitek Cyborg). This works for me because my view keys are on my hat on the stick but I still use "5" on the number pad for the "Up" look. What this all means is my hand is hovered over the number pad and I can change trim and views very easily.
Soooooo - in a fight the speed will change - as it does you will find it more difficult to maintain the aircraft flying where you want it without major stick inputs to correct out of trim forces (roll and pitch) - this is particularly noticeable if you get into a slowing turn, climb or steep dive. So then you manually trim to get the stick back in the middle - I find for instance that as I wind into a turn in a spit I will trim back and back as the speed falls and if I dive hard I will feed in right aileron to keep things straight.
The one I don't bother with in combat is the rudder and I can see now that I urgently need some rudder pedals because being out of trim in Yaw (rudder) is THE biggest energy loser and turn limiter. However you just can't keep the ball in the middle (on slip gauge) using the keypad because it changes so fast and I find the twist grip on the stick next to useless.
If I happen to live and want to leave a fight I pick a point to shallow dive for and set up the dive. I then use SHIFT X to fly away and relax.
I also use SHIFT X a lot in bombers to do the return to base - throttle back a bit when clear of the target and dive to achieve say 1000 ft/min rate of descent and hit SHIFT X - that gives you 10 mins of easy descent at good speed to lose 10,000ft enroute to landing and gives you the freedom to hop round the gunner positions to check for enemy (just don't go into tail gunner postion as it goes to level while you're in the tail - don't know why)
As a dweeb I often lose track of what I'm doing in a furball - particularly after a couple of B&Z passes and then I'll break away, fly level for a moment, engage X to set trims for level flight then immediately break out - at least I know then the trims will be somewhere near - a start point if you like.
Hope this helps Terra
Sparks
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Ok I am green as grass in this sim so I have to ask alot of questions of you all. First off, I know about the Auto pilot modes: Auto level, auto climb, auto angle. But what is auto trim? and is there a way to set somthing like a macro for trim setting for differint situations?
thanks
Vati
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oh one more then, is there a Downloadable manual for ACES that I have missed somewhere?
Vati
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Good luck and Good hunting
[img]http://home.earthlink.net/~spitfiremk9/eagle.gif[img]
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ufff too mouch stuff I will try to first get confortable with angle-trim them ...
thanks to all .
Sparks , I will try this things you say and yes we need urgently a rudder pedals, to fly this game. now watch what I use to fly this game:
no rudder pedals
a 2 button joystick (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) (one of those that you can use it just 3 months them is crap)
I do everything with my keyboard because the 2 buttons of joy now are bussy with the shot actions (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
maybe this is why I dont have founded the real use of trim , because I have my hands to bussy with flying viewing throling , etc
God I need a thirt hand (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif).
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Vati66:
Check out the page I mentioned at the top of the thread:
I have an article here on Auto Trim and some examples of how to use it.
http://users.andara.com/~sconrad/trim.htm (http://users.andara.com/~sconrad/trim.htm)
The game help resides on the web site, and is linked from in the game. If you want to check it out offline, just start at HTC's web site. http://www.hitechcreations.com/ (http://www.hitechcreations.com/) Select the Help link on the navigation bar on the left side.
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Lephturn - Chief Trainer
A member of The Flying Pigs http://www.flyingpigs.com (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"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
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HI vati66, here is Indians manual (http://www.geocities.com/tltoon11/AHFlight.html), haven't checked to see if its up to date. But remember iot to be very good. I hope Indian does't get mad at me (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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I'm with Andy on this. In RL trim is a workload issue. That little (relatively) trim tab doesn't supply some large, magic amount of force that will let you gain angles on your mis-trimmed brothers. Full control authority is available even when you are mis-trimmed, assuming you're a big studly guy that can pull the stick to its limit.
It's true that back then stick forces could be much higher than they are now with our 3000psi boosted controls, so trim could be a "fatigue" issue if the fight got long. But don't forget the adrenaline factor either.
In the game, as in WB you do have to trim correctly for max performance. There's some reason for this in the FM, of course. It's just the way it is here, so accept it and trim.
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Toad. Are you saying after all the snide comments about easymode dweebs, in WB. That easymode is a more realistic FM.
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Easymo,
First allow me to clear one thing up:
I am NOT the WB Toad. So if he made any comments about Easymode, it was some other guy. I was Toad in AW way back in early DOS version days. I had to be TOED in WB because my squad was late to move to WB. I got here first though! (I suspect he has beat me to WW2Online though.)
Now, to the point.
No, what I am saying is that TRIM is not a PRIMARY FLIGHT CONTOL in any airplane. That may not sound very deep or OTOH it may be confusing to some.
Basically, what I'm saying is that you don't "fly" the airplane with trim. You don't go rolling down the runway and then put in a bunch of trim to rotate. (Although that CAN be done, it's not real efficient nor is it an approved procedure.) You rotate with the stick, holding backpressure and THEN you trim out the stick force to hold the particular climb speed or angle that you desire. This allows you to pretty much leave the airplane alone while you do other stuff, like reconfigure the aircraft or talk on the radio or check your map or tune the nav aids.
THIS is what Andy was talking about when he said relieves the pilot workload.
The other main point to remember is that 99% of your control authority is available even when your are way out of trim. When you move the elevator to the "up" stop, you are getting all there is to give, essentially, even if the trim tab is not correctly trimmed. Most trim tabs are just a small fraction of the size of the control surface that they trim.
I think (don't know) that the game FM's use trim as primary flight controls. I remember someone saying, for example, that our autopilot actually works through the trim coding. I believe that may be correct. You can be in level flight, put in one tap of trim and get a 1500 FPM rate of climb as a result. That's not trim, that's a flight control. One "dit" or 1/2 turn of trim might give you 50-200 FPM or so realistically.
Hope this helps explain what I said.
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Reread my post. I did not mean to single out toad ( either one (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)). I was commenting on the antieasymode, player posts that started with the opening of the ACA. And still continue, on AGW.
I know nothing about real aircraft. And am forced to rely on RL pilots for info. I will say, I have wondered about this. Ive looked at alot of WW2 fighters down at the galveston field. I was very supprised to see how small the trim tabs were. considering the effect they have in both WB and AH.
I dont object, If this is done just to make the game more interesting. In the end. Keeping the plane in trim during a fight is more fun. It keeps things from getting boreing.
But What you posted has got to make some of the, realsim at all cost, boys stop and think.
[This message has been edited by easymo (edited 07-22-2000).]
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Toad
Good post. Better said than mine.
easymo
The 'realism' thing is always going to be an issue, I think. For some, it's like the Holy Grail...out there somewhere, but never found.
Sometimes, we seem to lose sight of the 'fun' in our attempt to recreate a RL atmosphere. All the talk about 'immersion' and 'suspension of disbelief' can be counter-productive. No better example is the state of the sim business at present. We may have contributed to the downsizing of the air combat sim genre by our ever-present demand for greater levels of 'realism'.
In some ways I see one person's 'realism' as another's gimmick. Some padlock or external views come to mind. In AH, auto-trim modes do also...WW2 aircraft had no such feature, and to have some pilots advocating using these during an engagement is, from a 'realism' viewpoint, downright silly.
In this regard, part of me says 'no problem'. If that is what brings fun to the sim for some, then fine. BUT...if that feature in fact provides a competitive edge, then I think we've gone too far.
Why? To begin with, the added performance aspects of the feature is not discussed in the sim documentation...so how are people supposed to learn about it? Are we playing "I've Got A Secret"...the cool guys know and the dweebs don't? Then, as Toad said, the aero effects have been over-modeled...to the detriment of realism. Lastly is the fact that pilots don't use trim in this manner in RL anyway...if they don't, why should we in a sim?
And so the debate goes on...! Personally, my vote is for a sim that puts its money on superior graphics, a comprehensive set of views, rock-solid multi-player, and a reasonable flight model...I'll not get too concerned about the 'realism'. Realism is for RL...our hobby is just for fun.
Andy
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Do a little experiment with trim, control surface deflections and the external view to see how it "works"....
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Flying a zeke in warbirds, in a 90 deg banked turn you could feed in up elev trim and gain significant angle - sometimes just enough to get your solution. I'm not sure how well this works in AH.
I do know you really have to be nimble with the trim to fight the 109-G10.
Time and time again elev trim has helped me to pull out of dives when nothing else works (except maybe better speed management (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)) You have to be ready to feed in left aileron trim in the high speed dive too.
You can't really fly this plane well without attending to trim. After reading the pilot's report on Andy's link, the 109 sounds like it was not that easy to fly in RL either.
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Just to add to the conversation here is a post from Earl 'Dutch' Miller, from the 350th FG, on trimming the Jug (P-47-D-R25 flyer I beleive. the same group the Brazilian Jug pilots flew with in Italy)...
"The P-47 had its rudder trim control toward the floor on the left side of the seat. As Dan (an AW guy) reported, the Me109 had no trim adjustable in flight. Hugh Dow, who reconstructed one in Sardinia, said that it was tricky on takeoff because of this. In fact, while Dow was on leave to the States, "Pee Wee" Page pranged it on takeoff because of this.
In divebombing, it was important to have the needle and ball centered at the moment of bomb release or the bombs would impact left or right horizontally of the target. Unless the aircraft was retrimmed, it would be practically impossible to maintain the proper rudder pressure for this. As I began my dive, I would reach down and give the knob three twists counterclockwise. This would over trim the aircraft at that speed, but would be about right on at the bomb-release speed. One had to retrim after the pullout. We had pilots with control cables severed by enemy fire who could maneuver the aircraft by the use of rudder and elevator trim and thus were able to return to the base. Once there, the aircraft was headed out to sea and the pilot bailed out over the field...."
-Westy
[This message has been edited by Westy (edited 07-22-2000).]
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Gunthr
Trim certainly can help pull out of a dive...in AH and in real life.
The reason is that the pilot retains the ability to move the trim surface at high indicated speeds when he has otherwise lost the ability to move the ailerons or elevator due to air loads. The pilot report mentioned this and commented upon the poor mechanical leverage the Me-109 pilot had in roll control. The air loads on the elevator, aileron, and rudder can be too strong for a human to overpower.
To explain this, I think of someone trying to open a car door at 100mph. The force of the air flowing by the door makes it tough to open the door up...and the more the door opens, the harder it gets to move further.
So how does aircraft trim help in situations like this? Using trim would be like having someone on the outside helping you to pull the door open...it's added mechanical advantage, pure and simple.
Westy
Your A2G example is good. I used to teach the same thing in RL fighters. On the way to the gunnery range, I would accelerate to release airspeed and then trim out the aircraft. In my case, I was mostly trying to trim out the elevator, but I would always double check the rudder 'ball' also. Aileron trim was not a significant factor and even if it was off, this would not adversely affect weapons accuracy.
Andy
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Ahheemm guys a lot of the airplanes we are talking about are a little bit faster and have a little bit more power than your favourite Cessna/Piper but yet still have the same unpowered flight controls (push rods and or cables) ... this means some of these airplanes are NOT controllable when out of trim (under the worst conditions)!
I dare to say that any High power tail dragger pilot will tell you never EVER to attempt a takeoff with the trim not set for the takoff position (rudder, as well as all the other trims) if there is one.
In AH we are flying basically conventionally controlled aircraft with a "fly by wire" stick .. therfore to get optimum performance and even controllability in some phases of flight (high speed dive, and slow speed manouvers) you NEED to trim the aircraft properly. This is mainly because you we have no feedback as you would have in real world through your control stick.
(your aircaft is properly trimmed when it does what you input with your stick e.g. when the stick is centered it should not roll and or pitch up/down, yaw)
DW6
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DW6
>>... this means some of these airplanes are NOT controllable when out of trim (under the worst conditions)!<<
Nope. Not true. You misunderstand trim controls. Read Toad's post again...he explained it well. A pilot will retain control over his plane if the trim settings are at full deflection...he'll probably have a uncomfortable time muscling the stick and rudder in maintaining control,but he'll be able to do it. Aircraft designers simply don't design trim controls that are so effective they can over power the pilot.
Now, that's not to say that trim malfunctions are not serious...they are and in some aircraft are a full blown emergency...but they are controllable.
>>I dare to say that any High power tail dragger pilot will tell you never EVER to attempt a takeoff with the trim not set for the takoff position (rudder, as well as all the other trims) if there is one.<<
True on this. But, again, let's understand what's going on here. The engine power will cause the nose to swing on takeoff. In a tail-dragger, the pilot corrects for this with rudder.
He can do this two ways. He can push the rudder in and hold it in a deflected position during the takeoff...or he can set the rudder trim to offset the rudder the same amount and thereby save himself the work of having to do it himself.
The result is exactly the same...a rudder that is deflected to provide a yaw force to offset engine torque.
Andy
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I think leph hit it on the nail when it comes to WWII fighters- The aileron and elevator trim was used in RL to make it easier to control and line up a fine shot control. Rudder in RL I don't think was near as important as it is in AH- they just used the pedals and accepted the slight drag induced. While the pilot has complete control despite the trim conditions the extra deflection needed to overcome a badly trimmed surface made for more E loss and drag. However just as in RL when lining up a shot I usually have my trim so that my plane requires almost no input from the stick to keep my lift vector from straying, and usually is just slightly pulling me up or down- I find it easier to line up my target by adjusting the pressure than trying to add then compensate.
In AH I usually use the level auto trim to center my controls then do all the rest by hand- the occasional angle trim during brief extensions to center my trim. In combat I do not usually adjust my trim during BFM unless the extra deflection is interfering with my control- ie. during a loop I might trim elevators near the top if it is making my stick move too far to keep the plane on the angle I want. However in firing solutions I quicly put the trim very close to allow me greater accuracy in my shot.
My advice is to try flying the plane in many many BFM at different altitudes and speeds and trimming her by hand to see what she needs to stay in "perfect trim". Then in combat anytime you need it you will be able to do it without thought. In the La-5FN I can stay very very close to trim with my elevators and ailerons simply by knowing what I have to adjust during the manuevers by practice. This means I have very good accuracy with her guns- compared to the YAK where I am still learning and have much less control.
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Anyone out there have a Pilot's Operating handbook for a P-51, a P-47 or an F-4U? Particularly would like to see the page/pages for the Taxi and Takeoff Checklists.
Thx.
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Funny thing that there are so many loss of control on takeoff accidents where the cause was improper trim setting ..
I don't know what we are arguing about here Andy ... he'll not be able to fly the sim in an overly complicated manner if he's not trimming.
Toad:
F4U POH:
Item 10. Standard Checks for all Flights (Before Takeoff)
Item 18-20
Rudder Tab - 6° Nose Right
Aileron Tab - 6° Right wing down
Elevator Tab - 1° Nose up
Sorry can't put the page up because i have no scanner..
This is a reprint available at Amazon ISBN 0-87994-026-9
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Duck,
What's the total amount of trim available in those axis?
In other words, how many degrees of rudder trim are available Right and Left? Same for Aileron, Same for Elevator up and down?
Also, do they post any notes, cautions or warnings in the text concerning use of trim for T/O?
Thanks!
[This message has been edited by Toad (edited 07-23-2000).]
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DW6 and Toad
From the F4U Pilot's Manual, the next paragraph following the steps outlined in the post above:
(http://www.doitnow.com/~alfakilo/trim1.jpg)
DW6...please not the qualifying statements regarding the rudder trim position. The rudder rim setting is there to assist the pilot in holding the required rudder input to counter engine torque...it was not the lack of rudder trim that caused accidents, it was the pilot losing control as a result of failure to use the rudder in a correct and timely manner.
I am not trying to make an argument. These posts make clear that some do not understand trim, plain and simple. I'm not surprised. Trim is somewhat of a 'Johnny Come-Lately' in flight sims...it doesn't help simmers to understand how to use it if a sim models it incorrectly.
Andy
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Toad
The picture of the trim control shows a plus or minus '20' on the elevator and rudder trim gauge. I cannot make out the markings on the aileron gauge.
Andy
[This message has been edited by Andy Bush (edited 07-24-2000).]
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Andy,
Thank you!
I see you have already grasped the point I was going to make. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Yet another way to view it:
In the "new" scheme of things, WARNINGS are put in flight manuals when experience shows that you can hurt <well, usually "kill" (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif) > somebody if you don't follow this advice. CAUTIONS give information that can avoid damaging your airplane. NOTES give advice that makes flying the plane a lot easier or more efficient.
What Andy posted above is an "old scheme" WW2 NOTE. "The rudder force required to maintain a straight run will be high unless the rudder tab has been set to approximately 6 degress Nose Right prior to the start."
It clearly doesn't say "Hey, there won't be enough rudder available to successfully takeoff and you'll crash and burn!" <WARNING>
It clearly doesn't say "Hey, you might run off the side into the grass unless you do this!" <CAUTION>
It's a NOTE that says, "Hey, make life easy on yourself...use a little trim."
If you don't use it at all, you'll simply need "high" rudder force. Not "impossible force" or "incredible force" just "high". That means they expect every pilot to be able to provide both "normal" and "high" levels of rudder force...and "low" as well.
Is there anyone here who really believes that an F4U could not successfully takeoff if the rudder trim tab was completely removed from the aircraft?
Trim is not a primary flight control. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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for loss of control i wasn't refering to the F4U in particualr .. i was talking about many and many general aviation aircraft...
See my point is that pilot workload is a very important thing to consider .. i know that Trim isn't a primary flight control but sure as hell it is important enough for all of us to recheck it's position before departure for example.
My point is why add pilot workload when this mental and physical capacity is needed to fly and FIGHT (here ins the sim) with the airplane. This is especially true as there are no tactile imputs (apart from the centering spring of your stick..) that help you keeping your orientation.
(btw guys i'm a RL pilot as well, there are more of us here than you might think)
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Duck,
I'm not sure of the point you are making.
I have no problem with the idea of trim in a sim.
Trimming for most RL pilots is such an ingrained procedure that they don't even consciously think about it. I'm sure you're that way in what you fly.
What I'm saying here is that trim is a little TOO important to the flight model. It was that way in WB too. And we don't have the tactile feedback through the stick prodding us to unconsciously trim as we do in an airplane. You sorta have to "just know" and that's probably pretty hard for new guys to develop a feel for. Heck, I sure don't have it completely yet.
Now that's all fine if you are adding "difficulty" to the sim because you want to simulate a heavier pilot workload. Like you can't put all the stuff a pilot would have to do, like managing rpm and manifold pressure, arming and charging the guns, switching fuel tanks manually, trimming, tightening laps straps, etc., etc.
But to me, peak aircraft performance here seems a little too dependent upon trim. You and I both know that you can get essentially all of your control authority in 98% of your flight situations even if you are pretty out of trim just by moving the stick till you get what you need. So, trim here in relation to RL is overemphasized.
That's all I'm saying. But I can accept that they made it that way if it's to add "complexity" or "difficulty".
Does that make any sense? (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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yea makes sense... guess after rereading some of the above we were kindda trying to say the same thing (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif)
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OK!! It seems we've got things back on an even keel!
So I'm left with the question of "What's the point?" with regard to how trim is modeled in this sim. All of this discussion seems to have led to these ideas:
1. Trim is not a primary flight control. It is a secondary flight control intended to assist the pilot in holding the flight controls in a particular position...this is necessary due to the airloads on the flight control surface (aileron, elevator, rudder) in flight.
2. Although unconfirmed by AH (and unmentioned in AH documentation), some experienced AH pilots believe that a trimmed aircraft will enjoy an energy advantage over a similar, but untrimmed, aircraft. The example given is a comparison of turn rates in a sustained turn.
3. This 'energy advantage' has not been shown to exist in a RL situation, and no aerodynamic proof has been offered to confirm this.
It seems only right that we put this puppy to bed once and for all. After all is said and done, it doesn't matter if this trim advantage is aerodynamically correct, nor does it matter how RL aircraft are flown in BFM. It only matters how AH pilots fly AH aircraft.
Therefore, we should expect AH to provide some documentation, however brief, on this subject...if only to keep the playing field level.
Andy
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Problem with AH trim is that it DOES reduce maximum control surface deflection if you are trimmed fully in the opposite direction. Use the external view while stationary on the runway to see for yourself.
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oooooooooooooooooh!
DON'T like THAT!
Thx, Juzz...will take a look at this.
Unless they are modeling that us weak sisters can't fully overcome a trim tab (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)
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Me either!
I just looked at it...and for sure, the elevator has a greater deflection when fully trimmed 'nose up'...that may well account for the increased performance that some report.
The only problem is that this is not how it works in real life!
So be it. We've talked this to death. Pilots...be advised...to get max performance in AH, trim your stick 'nose up' when honking on the pole. It may not be realistic...but what the hell...a kill is a kill.
Andy
[This message has been edited by Andy Bush (edited 07-25-2000).]
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Originally posted by Vati66:
But what is auto trim? and is there a way to set somthing like a macro for trim setting for differint situations?
Auto trim is what you referred to as the "autopilot". AH doesn't have an autopilot as such, but the various X modes lets the game set the trim for you to keep the plane at a certain angle of attack or speed. This can also be achieved by hand using the manual trim keys (I and K for elevator, J and L for rudder and M and . for ailerons).
I have the elevator and ailerons mapped to a hat on my stick, so that I can trim for a dive in combat, and quickly readjust for a zoom climb so I don't have to heave back on the stick with all my might. When strafing you also have to trim, or use the pedals, to keep the ball in the middle, or your aim will be off.
Trim isn't all that useful for maneuvering in combat, but setting it right (i.e. for the speed you'll be using in the fight) helps relieve some stick pressure, and makes it easier to fly and aim.
It's generally easier to pull on the stick than to push when aiming, so I set my elevator trim to pull the nose down a tiny bit when shooting, or preferably to eliminate all stick forces. This ensures that the bullets go where the sight is pointing, more or less.
Rickenbacker
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I've been buffing a while, and just new to fighters and dealing with torque. I haven't tried it yet, but was just wondering if draining fuel first from one of the wing tanks to make it lighter and the other heavier would help offset torque without the need for a lot of trimming.
I know it's probably much easier to use the tabs (that's why they are there in the firs place) just wondering if anyone does this, or something else to counter torque in a different method
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"trim is not much use in comebat". I would have to strongly disagree,rick. I have all 6 directions mapped to my main buttons. I have my fingers danceing on them all through a fight. Plus the flaps. This game is trimming and shooting.
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Well, easymo, it _shouldn't_ be dammit (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif).
IRL I use trim only so I don't have to hold the stick forward manually during aerotow, then after that I trim the plane to fly 90 km/h (the most efficient speed in that plane, i.e. max distance for min sink) and don't touch it until it's time to land, when I usually trim the nose down a bit since it's hard to maintain speed with airbrakes out.
I can still get full control surface deflection, though, however the trim is set. I know that's not how WB worked, but I'm not sure about AH. You should be able to fly the same without trim changes.
In spite of all the above, though, I do use trim in combat, but not to fly the plane, only to minimize the forces I have to apply to the stick (makes it easier to aim, and I sorely need some help there (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)).
Rickenbacker