View Full Version : Trim on a slider anyone?

06-23-2005, 10:01 AM
where is rbj when you need him?

06-24-2005, 02:27 AM
Wow! I haven´t heard of him for ages!!! He made me laugh so much.
I do have my pitch trim assigned to a slider. Works like a charm.

06-24-2005, 03:24 AM
Yesterday I sat opp the trim on my X45 sliders.
Spesiall my groundstraffings with BF110 improved
Also on the P40 shoting down Jap bombers and Zeroes was haighly improved.
The gunnery platfor is now much easier to aim exactly.

06-24-2005, 03:30 AM
Since it's changed, I've not had any problem with 109 or P-38 compression. Basically went back to using trim as a secondary elevator like I did in IL-2.

I really wish they'd have left it the other way. I don't want to use this exploit, but ignoring it would be a handicap.

06-24-2005, 04:01 AM
what is "the other way"? I assume that the whole debate is that a pilot would never reach down and trim his aircraft while in the middle of a turning fight-right? i.e. -not- that trim can't add significant amounts of lift...

06-24-2005, 04:32 AM
You´ll be surprised how trimming while dogfighting is useful...Especially pitch trim...tighter turns.

06-24-2005, 04:44 AM
And thats why we'll have 109s & Mustangs turn like Gladiators. Really, if you want it that way, just fly on arcade servers please http://forums.ubi.com/images/smilies/51.gif

06-24-2005, 04:46 AM
And use it they did... they used whatever they could manage to get to in the fury of trying to stay alive... they would have honked the horn if it had one and it would have effected the plane.... Bud Anderson said that they used trim.. but often stuff was happening so fast, your hands were flying all around the cockpit and you didnt think about it... you became one with the planeand if you wanted the plane to do something you did what you had to do to get it to do it but you also were aware of the limits because you knew to try to get it to do something it couldnt in a fight meant almost certain death.

06-24-2005, 05:13 AM
Originally posted by Bearcat99:
And use it they did... they used whatever they could manage to get to in the fury of trying to stay alive... they would have honked the horn if it had one and it would have effected the plane.... Bud Anderson said that they used trim.. but often stuff was happening so fast, your hands were flying all around the cockpit and you didnt think about it... you became one with the planeand if you wanted the plane to do something you did what you had to do to get it to do it but you also were aware of the limits because you knew to try to get it to do something it couldnt in a fight meant almost certain death.

No offense Bearcat, but try this: in qmb start a 109 at 3000 m and make a dive at approx. 45 degrees. Let speed build up to about 680 - 700 km/h.

Now, pull back fully on the stick and trim and the same time. That simply could not be done in reality due to physical limitation of the pilot. At those speeds in 109 you needed both hands to pull the stick, what a finnish pilot had to do is alternate by pulling with both hands and let go with one had and trim then pull with both hands again etc.

So no, i dont think its realistic in FB. http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

06-24-2005, 05:21 AM
Right-on Bear...anybody who doesn't think trim was used in dogfights, has never flown real aircraft, and needs to do his research.

Here is a quote from Chapter 1 of Clarence "Bud" Anderson's To Fly and Fight. This is the chapter where he discribes the most intense turning dogfight of his life, against a Bf-109:

"Any airplane with a single propeller produces torque. The more horsepower you have, the more the prop will pull you off to one side. The Mustangs I flew used a 12-cylinder Packard Merlin engine that displaced 1,649 cubic inches. That is 10 times the size of the engine that powers an Indy car. It developed power enough that you never applied full power sitting still on the ground because it would pull the tail up off the runway and the propellor would chew up the concrete. With so much power, you were continually making minor adjustments on the controls to keep the Mustang and its wing-mounted guns pointing straight.

There were three little palm-sized wheels you had to keep fiddling with. They trimmed you up for hands-off level flight. One for the little trim tab on the tail rudder, the vertical slab which moves the plane left or right. Another adjusted the tab on the tail's horizontal elevators that raise or lower the nose and help reduce the force you had to apply for hard turning. The third was for aileron trim, to keep your wings level, although you didn't have to fuss much with that one. Your left hand was down there a lot if you were changing speeds, as in combat...while at the same time you were making minor adjustments with your feet on the rudder pedals and your hand on the stick. At first it was awkward. But with experience, it was something you did without thinking. like driving a car and twirling the radio dial."

06-24-2005, 05:21 AM
This is a sim..... not a holodeck.... AFAIC it is modelled the way it is modelled and I have been too busy having fun with every version of this sim from IL21.0 to FB 4.01 and each incarnation in between right or wrong to waste my time trying to find holes in it.... but hey....

06-24-2005, 05:33 AM
bss_vidar got a chance to take a spin in a dual-seater p-51 mustang. he reported the a/c was very very sensitive to any change of speed. even if the diff. was a mere 5mph, the trim would be drastically affected. he also said if i remember right, flying the p-51 was basically 'constant trimming'.

on the other hand, what was mentioned about the 109 in a dive from that speed, i would have to agree somewhat. ww2 planes wasnt our modern 'fly by wire' and computer assisted controls. and neither did the pilots of any country have g-suits to counter-act the g forces that u would pull in a dive like that. if u managed not to rip the wings off that crate, i bet ya 2-1 that u'd be practically standing on the instrument panel in trying to pull out and trim at the same time. in fb, we can get away with gettin ourself's into a fubar situation like that, but i highly doubt u would seriously try that stunt in an actual 109 there bearcat...if u lost, u lost more than a plane, u lost ur life as well. maybe what should be done is with the way things are modelled: fly the plane as if ur actual life depended on it; maybe then we'd have less friendly fire from idjits that shoot over the shoulder. something that most likely wouldnt be repeated in rl cause the shooter would most likely get punched out by the almost shoot-ee http://forums.ubi.com/images/smilies/88.gif

06-24-2005, 06:38 AM
Maybe the thing to do would be to simulate the stiffness on the controls.. sort of like a modified blackout... where you would loose some contriol at certain speeds or angles but not necessarily black out. Then again differnt pilots had different strengths... In reading Redtails Balck Wings.. they had different accounts from several pilots... one guy.. who was all of 112 lbs had to practically stand on the rudder to keep his p-40 from veering off into the woods.... another guy was described as a "bear of a man" who was so strong that he could do things with a plane that many pilots couldnt do and would usually stress the airframe to its limits because of his strength.

06-24-2005, 07:32 AM
I like the idea of stiffness at highspeeds, another similar would be to gradually make trimming slower at high speeds. It would be a reasonable way to simulate the pilots workload and so slower input on trimming (like in the 109 dive scenario).

So at slow speeds, trim as now. But in high speeds maybe "trim lag" as in patch 3.04? But then again, im no programmer i dont know if its possible or if its the best solution either.

06-24-2005, 07:42 AM
the 109 driver, hanz really built himself up to pull the manuvers he did in africa; making his eyes adjust to the sun glare, and had very strong legs to deal with the rudders. and what b.c. said would be true; a 'city slicker' might not have quite as much strength as 1 that grew up in farm country where that would make any1 rather strong after a couple of years.

for some reason i watched 'battle of britain' movie. the spitfire was able to go into a dive spiral and evade the 109, but the 109 would also match the spit turn for turn. maybe, just maybe, the 109's torque prevented the pilots' from following the spit in a spiral dive. then again, it could have just been for the movie.

the p-40 was renowned for having wicked torque on take-off. unless i'm wrong on this, shouldn't the 109 roll and turn better to the left than right like the zero's did?

06-24-2005, 03:46 PM
All aircraft will roll into the engine torque better than against it. Some design factors on some aircraft make it harder to overcome than on others.

Trim does NOT ADD ANY AMOUNT of lift. In a way it "preloads" the stick in the direction desired by aerodynamically moving the control surface and for all intents and purposes, is identical to moving it manually with the stick. So if it takes 40 pounds of stick force to get some amount of control surface deflection at some airspeed, then some up trim setting might add (by aerodynamic deflection of the control surface), for example, 6 pounds. Therefore you only need to come up with 34 pounds of force.

Control stiffness is already modeled, what more do you want?

If you REALLY want to model it, then Oleg will have to split the total stick force available between two hands. If you are making a left hand adjustment to the controls (throttle, prop pitch, mixture, trim, etc.) then you only get half (or some portion) of the total stick force.

It doesn't take many hours in an aircraft to realize that if you can't get enough control deflection in the direction you want then you need to add trim in that direction. F4F Wildcat pilots added full up trim while diving away from early model zeros so that they could pull up so hard the the zero would break the tail off if he followed. It would black the pilot out but only for a short time and there was no possible way the zero could follow.

All this BS about pilots having so much to worry about that they couldn't adjust trim is just that, BS. A significant part of pilot training is how to juggle many problems at once and when your butt is on the line and you need to add trim, then you just add the freakin' trim, end of story. High speed compressibility in aircraft such as the P-47 and P-38 could be controlled by a rapid reduction in throttle to idle (ie, bend it back against the stop), the application of full up trim, and waiting it out until lower altitudes and denser air (the increased speed of sound is what did the trick) was reached. Of course, if the aircraft broke up before that you were out of luck.

Has anyone done a devicelink test to see if the trim rate is limited like it was pre 4.01? I have rebuilt my development machine so I will have to download all the aircraft instrument components before my app will compile. I'll do that this weekend just to be sure but it doesn't feel any different to me.


Obviously the aerodynamic moving of control surfaces only applies trim mechanisms that use a trim tab as opposed to moving the entire stabilizer.

06-24-2005, 05:02 PM
Either I didn't fly when the last time trim was on a slider or I wasn't aware that that was why I kept getting waxed...noob syndrome...but I now know what all the fuss is about.

I'd rather leave the trim instantaneous and reduce the authority it has on controls but I've seen time and time again planes do high speed bat turns with it...seems to help in high energy states more than low energy states.

Just take a 109G2 and dive it from 5000 meters get it going about 800km/hr...the elevators are a little heavy and takes a little to pull out...now do the same thing with bat turn and you have instant UFO...blackouts for everyone!

Guess I haven't been around long enough to know the past history, but the trims effect on control effectiveness is ...well...baked! Immersion killer as far as I'm concerned.

I got a feeling that the instant trim is necessary with the new flight model because of all the trimming required for good flying...maybe there will be a compromise of sorts in a later update...lets hope!

06-24-2005, 05:06 PM
Did IQs drop sharply between the last patch and this one?



06-24-2005, 05:31 PM
But... it's not instantaneous. It's a bit fast; it only takes ~4 seconds to go from full up to full down (I'm not sure if it's different per plane), but it's exactly the same speed whether you bind it to a slider or you hold down the keyboard key (barring the initial repeat delay). Trim doesn't affect the maximum (non-aerodynamically limited) deflection angle of you controls, either.

I really don't get what all the fuss is about.

06-25-2005, 09:42 AM
Trim was used to keep an aircraft flying in a straight line with no stick inputs...it was as instataneous as a pilot could turn the wheel.

It did not reduce stick forces from 50#'s to 20#'s, it did not overcome compressibility and it did not change the turning radius of an aircraft...it did, to a small degree, assist in turns and to a small degree lower stick forces for a given manuever...the operative word is to a small degree....now I don't have a quantitative figure for that, but I know the current modelling of trim is way too effective in terms of decreasing turn radius at a given speed...the higher the speed, the worse the affect.

06-25-2005, 10:59 AM
Good reading here:


Especially useful for the guys knowing nothing about the subject.

06-25-2005, 11:38 AM
well, I for one can€t say if its accurate or non-accurate, but its back. For those that dont know, they took the instant trim out of the game (Ok, I know, not totally out of the game) several patches ago. Personally, I always figured, instant reaction or not, it was just another part of the "game" that had to be learned so you could be competitive.

And just to be clear, I have NO problems with it. I've said it before, as long as we're all playing with the same game, its all good. I think Oleg and company have done a fantastic job insuring we all are in fact playing with the same game. And that€s why this should be mentioned, as you can see some newer members of the online community, have never applied the technique. Anyway, rbj would be in heaven. I cant believe we haven't seen Super Greg bobbing his uni-brow on these lovely pages.

So boys and girls, like it or not, good or bad, right or wrong, I know its always been there to one level of another, but now its pretty much back with force. Once again it seems if you really want to run with the big boys online, you better get you some Trim on a Slider action. I use my momo wheel, and all the buttons are a big help too. Just slide it around the corner of my deck, and it even faced the right way. So explore all your options if you don€t have a hostas control set up.

Good luck. Have fun and play nice.

06-25-2005, 12:05 PM
Yep, you're right Supr. It's back. Along with induced cartwheels, speed hack, and reduced check time speeds. Just another phase we will have to get through. Doesn't keep me from flying. Just keeps me jotting down the jerks call signs. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

06-25-2005, 12:05 PM
it was as instataneous as a pilot could turn the wheel.

Have you ever even SEEN a trim wheel in real life, much less turned one from lock-to-lock?

now I don't have a quantitative figure for that

When you do, then post your evidence that contradicts Oleg's implementation.

Took out a misrepresentation here. I might post a clarification later.
-----End Edit

Which part of "the increased speed of sound is what did the trick" did you not understand?

How many hours have you spent in ANY type of aircraft flying at full power with full trim in either direction?

How many hours have you spent calculating the dynamic response of aircraft to control inputs?


06-25-2005, 03:01 PM
Trim is exactly the same speed whether it's bound to a slider, a hatswitch, or a keyboard key. It's really easy to test if you have a joystick with a throttle.

Why are we having this discussion? The trim wheel is directly connected to the trim controls. Your evil slider set the desired position of the trim wheel, the wheel turns at a maximum speed to get to that position, and the trim tab reacts at exactly the same speed as the trim wheel moves.