How the heck do you trim in a simulator?

[WK95]

Well, I actually do know how to trim. I've a Saitek Cessna Trim wheel and to trim, I just have to turn the wheel in the direction I need to until I no longer need to apply much if any forward or back pressure on the yoke. But that's the problem. In a real plane, to trim, the pilot needs to get his plane into the attitude and airspeed he wants to fly at. After that is achieved, he then uses, the trim wheel in the appropriate direction until no more forward or back pressure is felt. In other words, once the pilto achieved the desired attitude, trim is used to relieve control pressure.

 

In a real aircraft, as a result of trimming, the neutral position of the yoke varies based on the situation, attitude, trimming, etc. In a flight sim with non-force feedback yoke hardware, that neutral position is always at a given point due to the springs and does not vary. Thus, when trimming, I also would have to reduce the force I apply while at the same time using the trim wheel. This is obviously very different from flying in a real plane and has proven quite tough for me to deal with because there is no flying by feel when it comes to non-force feedback yokes. I always end up trimming too much or too little and getting my plane to the desired attitude is tough. Too bad force feedback yokes are so expensive.

 

So, just how do you properly trim your aircraft without having any "feel" for the plane?

[PPSFA]

Dont know about Saitek but my CH yoke trim's just fine, I use the rocker switch not the wheel, and just tap it. BTW, trim for airspeed, not attitude.

[lnuss]

You describe the problem very well. I use a stick, rather than a yoke, but the same observation applies. All you can really do is to substitute the spring pressure for the real feel, then trim until you don't need to apply pressure, ignoring stick or yoke position -- position is (mostly) irrelevant in real aircraft for most flying, if you think pressures.

 

So basically you have to adjust your mind to ignore position and pretend that the spring pressures are all you need, that they are really the control force feedback.

 

I don't know what the resolution of your trim wheel is, but it may not resolve to fine enough control, so it's probably tougher to get trim set so that you can be hands off for more than a couple of seconds -- even with the repeating button I use (finer resolution than most axes), it's rare that I can set a hands off trim without also making a slight throttle change and/or giving the stick a slight nudge one way or the other. The resolution in a real aircraft is just about infinite, since it's strictly analog (disregarding fly-by-wire types), while we have to deal with low resolution digital, among other handicaps.

 

Real aircraft are, in most respects, easier to fly than the sim on a PC.

[WK95]

You describe the problem very well. I use a stick, rather than a yoke, but the same observation applies. All you can really do is to substitute the spring pressure for the real feel, then trim until you don't need to apply pressure, ignoring stick or yoke position -- position is (mostly) irrelevant in real aircraft for most flying, if you think pressures.

 

So basically you have to adjust your mind to ignore position and pretend that the spring pressures are all you need, that they are really the control force feedback.

 

I don't know what the resolution of your trim wheel is, but it may not resolve to fine enough control, so it's probably tougher to get trim set so that you can be hands off for more than a couple of seconds -- even with the repeating button I use (finer resolution than most axes), it's rare that I can set a hands off trim without also making a slight throttle change and/or giving the stick a slight nudge one way or the other. The resolution in a real aircraft is just about infinite, since it's strictly analog (disregarding fly-by-wire types), while we have to deal with low resolution digital, among other handicaps.

 

Real aircraft are, in most respects, easier to fly than the sim on a PC.

 

Thanks for the reply. My Saitek Trim Wheel simulates 9 full rotations in game with 9 full rotations of the physical wheel so I think it has a high enough resolution.

 

Well, I guess this is really just something I have to get used to. Sometimes, I feel almost as if I'm "flying" with the trim wheel.

[WK95]

Not much help if you use a yoke but If you have/get a force feedback joystick (not too expensive - I bought an MS Force Feedback 2 on eBay) and use FS Force software (http://www.fs-force.com) you get "real” trim. The trimmer takes out the stick forces and the stick datum moves to the trimmed position. The stick forces are very realistic and fully customisable through the software.

 

That sounds great! But I already bought a yoke so I'm going to have to stick with it.

[Ragtopjohnny]

You can program buttons on your yoke for trim. I use the Goflight Trim Wheel module, but when I feel like not reaching for that, I programmed my Yoke to trim with one of the rocker switches on the handles and it is beautiful that way too.

 

Just program the buttons like I said, and you'll be fine. :)

[pvarn]

It reads to me as if you need to work with your trim wheel sensitivity a bit more.

Flying with the trim and your hands off is pretty much the spring loaded technique.

 

Your controller might actually be sending keyboard trim commands to the sim (numpad 1,7)

If this is the case (probably) then each pulse from the trim wheel sends one keyboard 1 or one keyboard 7 tap to the sim. You might benefit from editing the FSX key commands sensitivity for trim to much lower values. It's tricky to get this right. Set it too low and you have to move the trim too far and the result is over-compensation. Set too high and the result is even one pulse sends your altitude out of control.

 

If you can control the trim with the keyboard, you should be able to control it with the controller wheel. Try making the adjustments with the keyboard only, and when you get the feel right, change to using the controller.

 

-Pv-

[Rupert]

 

 

 

real aircraft are, in most respects, easier to fly than the sim on a pc.

 

true!

[pvarn]

Agreed when not faced with computerized airliners. Real world depth perception, peripheral vision, G forces and eliminating the rubber ruler of PC controllers makes a tremendous difference. Remember that kid who kept stealing airplanes with zero pilot training? Walked away from all his crashes.

 

-Pv-

[keefpee]

And what has not been mentioned so far is the settings in the .air file. I must admit that when creating my models I often find it difficult to get a balance between trim clicks & amount required overall to cover the C of G range & possibly flap operation. It can come down to the Cm vs Alpha graph slope as well as placement of the centre of lift, combined with the empty weight C of G, so in a nutshell the model can be rubbish or it can be easy depending on the skill of the creator.

Keith

[il88pp]

How to trim? (in level flight.)

To slow down: reduce thrust gently, then add trim to slow down and stay level.

To speed up: increase thrust, while she starts climbing trim down to speed up and stay level.

The stick stays centered, except for tiny corrections.

(practice speeding up in the ultralight.)

Speeding up takes time. Thrust up- climbing- trim down- level- speed increases- --- -she climbs some more! (because more speed.)- so more down trim- etc.

Want to climb?

Increase thrust, then trim to maintain airspeed (slight down trim required). The stick is used to start the climb only, then comes back to center immediately. (Just a 'nudge').

il88pp.

[Gringo6]

I use Chuck Dome's Autotrmp and it's super easy. Although it is a FS2000 gauge it works well in FS8 and FS9. Although I don't fly FSX much (computer doesn't have the uumph) I'd expect it to work in FSX also.

[pvarn]

" I'd expect it to work in FSX also"

 

Never safe to assume this. FS2000 was a crossover version where gauges compiled with older C still worked as well as the new ones. FSX allows no old gauges.

 

I suspect the OP was interested in trimming the Cessna models which is quite possible without add-ons. All that is really necessary is a solid understand of flight dynamics which real world pilots must learn. The only unrealistic part is learning how to configure your controller software/hardware. The thousands of FS pilots who fly these aircraft every day are proof a cheater gauge is not necessary.

 

" It can come down to the Cm vs Alpha graph slope as well as placement of the centre of lift, combined with the empty weight C of G..."

 

Yes, there are a LOT of bad models out there where poorly tested combos of aircraft.cfg inertia, COG, and fuel placement as well as air files copied from other models are as unrealistic as jet engine on a bird.

In THIS case however, there is a strong case the OP is referring to using a particular controller and configuring it for use on an FS default Cessna which is configured close enough to real world values to be not a factor in contributing to flight problems.

 

-Pv-

[PhantomTweak]

There are a number of "cheater" gauges (for FS9, only one I know, sorry) for trimming an aircraft with different methods. There is a "mouse trim" one that lets one trim with the central mouse wheel, there is EASYFBW.exe which moves the trim to match the stick position in increments, permitting one to relax the stick slowly to neutral, and is supposedly similar to the FBW systems on modern jets, both civil and military, and is a program (small) that runs parallel to FS. It has some limitations though, like no doing well on Aerobatics (in the break for military jets for example), and some autopilots don't react well to it at all. Having said all that, you can turn it off and on instantly with a simple joystick button press. Super easy to use.

There is a module,

RealTrim - Version 1.6

======================

 

Activate the trimming-feature via button while moving the joystick from deflection

to neutral. The movement of the joystick is converted into the opposite amount of

movement of the trim-wheel. This matches real-life where the pilot trims out force

felt on the yoke in ONE smooth operation - there's no need to chase the correct

attitude a second time with trim buttons.

 

that I think is explained well.

 

Those are just the ones I have installed. I use the RealTrim mostly, although I have used the EasyFBW for some jets (not military). There is also one I can't recall the name of, but it is a gauge you can put into the panel that shows the trim position, and if you click the top, marked AUTO, it acts much like easy FBW without the aerobatic limitations. I like it :)

Anyway, that's my take on the whole thing, not counting, naturally the original "correct" method designed into FS9.

Pat☺

[WK95]

There are a number of "cheater" gauges (for FS9, only one I know, sorry) for trimming an aircraft with different methods. There is a "mouse trim" one that lets one trim with the central mouse wheel, there is EASYFBW.exe which moves the trim to match the stick position in increments, permitting one to relax the stick slowly to neutral, and is supposedly similar to the FBW systems on modern jets, both civil and military, and is a program (small) that runs parallel to FS. It has some limitations though, like no doing well on Aerobatics (in the break for military jets for example), and some autopilots don't react well to it at all. Having said all that, you can turn it off and on instantly with a simple joystick button press. Super easy to use.

There is a module,

 

 

that I think is explained well.

 

Those are just the ones I have installed. I use the RealTrim mostly, although I have used the EasyFBW for some jets (not military). There is also one I can't recall the name of, but it is a gauge you can put into the panel that shows the trim position, and if you click the top, marked AUTO, it acts much like easy FBW without the aerobatic limitations. I like it :)

Anyway, that's my take on the whole thing, not counting, naturally the original "correct" method designed into FS9.

Pat☺

 

That feels like cheating by damn it, that's great. Now I've got to try to get it working on Prepar3D.

[WK95]

How to trim? (in level flight.)

To slow down: reduce thrust gently, then add trim to slow down and stay level.

To speed up: increase thrust, while she starts climbing trim down to speed up and stay level.

The stick stays centered, except for tiny corrections.

(practice speeding up in the ultralight.)

Speeding up takes time. Thrust up- climbing- trim down- level- speed increases- --- -she climbs some more! (because more speed.)- so more down trim- etc.

Want to climb?

Increase thrust, then trim to maintain airspeed (slight down trim required). The stick is used to start the climb only, then comes back to center immediately. (Just a 'nudge').

il88pp.

 

Thanks for explanation. Probably because I didn't understand this before, I had trouble trimming especially when I transitioned from climbing to cruise which requires throttling down a bit.