Manual trim question

[Mustaine]

I haven't seen this discussed ever on the forum, and just noticed this in the news archives on the HTC main page

Version 2.09 Patch 0 Released November 15, 2006

Changes from previous release
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    * Added a new Trim Set function. This a supplement to the manual trim system. At the instant you press the trim set button, it will see how much aileron, elevator, and aileron input you are giving and feed in trim to achieve neutral controls. The default key for this function is the <.> key. If you have ever remapped any of your keys, you will need to manually map this function.

does anyone know exactly how this works, or what exactly it does?

I was playing with it offline a bit, and it seems to show briefly in the trim indicators how much deflection you are imputing on your stick when no trim is set (and combat trim off).

other than that brief display, it seems to have no other function, and I am curious to the exact use of this feature.

[lengro]

It is an easy way to quickly make manual trim:

When combat trim is enabled, you can fly straight and level with your joystick in its center position.

Disable combat trim and then offset your joystick from the center until you fly straight and level again. Now press the dot key (.) and then recenter your joystick - your plane is now trimmed.

Remember you have to map the "set trim function" to the (.) key - it is not done by default.


lengro

[Rolex]

Originally posted by Pyro
Combat trim is simply a lookup table of trim settings.  For example, if you are doing 200 mph and have combat trim enabled, it will go to a table and lookup your speed and set the three trims to whatever corresponds to the 200 mph entry.  Combat trim is meant to keep you trimmed condition for just one condition- military power at a standard fuel and ordnance load.  Change your throttle settings, drop your flaps, change your loadout, etc. and combat trim may no longer hold you in a trimmed out condition.  For those conditions, you need to use manual trim to get your plane trimmed out.  If you use combat trim all the time, you'll notice that when you're on final approach with power reduced and gear and flaps down, you're out of trim by a good deal and are having to put in a lot of joystick and rudder input to hold your plane at the correct attitude.  If you want to get your plane trimmed out in these other conditions, you'll need to use the manual trim system when you're in those conditions.

As soon as you start dialing in some manual trim, your combat trim will be disabled.  To reenable it, you either need to press the combat trim key or there is an option in the flight setup that automatically enables combat trim whenever you leave autopilot mode.  

So you're on final with your power reduced and flaps and gear down and combat trim has you out of trim.  You're having to push forward on the stick to keep your nose from coming up.  You start repeatedly hitting the down trim key to alleviate this.  As you dial in more elevator trim, you can start relaxing the amount of joystick input you are giving until the stick is centered.  You would then rinse and repeat for the aileron and rudder trims and that should put you in a trimmed out condition.  

What the new feature does is move all three of those trims for you when you make a single button press.  Going back to the above example, how I would trim out my plane on final approach would be to hold the correct amount of elevator, aileron, and rudder input to keep the plane flying like I want it to.  Then I just hit the set trim button and it looks at how much input I'm giving to each axis and begins dialing in trim to get each of those axes back to a neutral position.  As it does this I just begin relaxing the amount of deflection I'm feeding into the joystick and rudder until they are neutral.  

This is just an addition to the manual trim system.  It doesn't replace anything.  If you don't use it, you wouldn't know that anything has changed.  

Although the outcome is essentially the same, trim is different in a PC sim versus a real aircraft because PC's have self-centering spring loaded sticks.

[Mustaine]

ok, so is it "instant" meaning they snap to that position, and I should be able to let go of my stick and it keeps that attitude / heading (sort of) ?

[Blagard]

Originally posted by Mustaine
ok, so is it "instant" meaning they snap to that position, and I should be able to let go of my stick and it keeps that attitude / heading (sort of) ?

The condition you want to trim to is that at the instant you press the "set trim" The trims themselves then crank to that position which may or may not be quick depending on how far they have to move! It must be almost two or three seconds to get from one extreme to the other.

Try it, i.e. hit the set trim when you are clearly out of trim and then watch the trims move.

[bj229r]

hmmm..does this take 'missing aluminum' into account?

[Schatzi]

Originally posted by bj229r
hmmm..does this take 'missing aluminum' into account?

As in the trim function knows youre missing a wing and automatically makes up for it? No.

As in: you hold your plane level with the Joystick, then press the new trim key. You can now slowly let go of the stick input as the trim "makes up" for the input. I guess thats a Yes for this interpretation.

[Blagard]

Originally posted by bj229r
hmmm..does this take 'missing aluminum' into account?

Schatzi has answered the question, but I thought I would add that missing aluminium often needs extremes of trim. Although the trim will attempt to even out your stick input, it is likely your control input will be beyond the range of trim to completely trim out for the missing bits so you will in all probability still need some stick input to maintain stable flight.

As once pointed out in another thread, aircraft with wing tanks may also assist in trim in this situation by burning the fuel in the wing that now appears to be heavy!;)

[bj229r]

Yah. I havent found any way to deal with missing half a wing---set various trims to extremes and fly somewhat normally, but autopilot screws them up and ya gotta do it all over agin

[Ack-Ack]

Originally posted by bj229r
Yah. I havent found any way to deal with missing half a wing---set various trims to extremes and fly somewhat normally, but autopilot screws them up and ya gotta do it all over agin

Lower your flaps if your missing half a wing.   makes flying easier.


ack-ack

[KayBayRay]

OK, I have read over the posts and replies about both Combat and Manual Trim. I think I understand how they work and are set for AHII. However I still seem to be forever fighting against control surfaces and some kind of Trim setting. Yes I am using the <.> command to reset the Trim when I stop manuvering but the air craft still seems to be trying to orient to some unknown positioning. Yes I have Combat Trim OFF, along with all the other bells and whistles like Anti Stall limiting and the other crud.

I would appreciate some advice on how I can get past this wrestling match with my control surfaces.  I sometimes want to rip the Trim feature out of my aircraft so I can be in control of the aircraft for a while  

Something else that is associated with this difficulty is I adjust the position of my view in the cockpit so I can see all my gauges but it keeps going back to some default setting where I can only see some of the gauges. I move the point of view back towards the rear of the aircraft and when I use my Top Hat view to check when I look back at the gauges the point of view has reset forward again. How can I lock this into the point of view I want?  Would be nice if I could actually see where my flaps were so I could use them properly.

Later,
And Thanks in advance,

kaybayray

[FiLtH]

In another game, I used manual trim alot. In there I had to settings I used. Fast and slow. Id fly slow, as slow as a knife fight would be, and fly straight. Then I'd count the clicks for eles, and ails, rudder, that would put me in a level flight at very low speed. Id do the same for fast speed. I dont use trim here though.

[lengro]

Originally posted by KayBayRay
Something else that is associated with this difficulty is I adjust the position of my view in the cockpit so I can see all my gauges but it keeps going back to some default setting where I can only see some of the gauges. I move the point of view back towards the rear of the aircraft and when I use my Top Hat view to check when I look back at the gauges the point of view has reset forward again. How can I lock this into the point of view I want?

When you have adjusted your head position for a view, you have to press F10 to save that new position.

Also notice there are 2 forward views where you can adjust head position:

1)  the default view (when no key is pressed)
2) the "look forward" view (press NumPad 8)

[Blagard]

Originally posted by lengro
Also notice there are 2 forward views where you can adjust head position:
1)  the default view (when no key is pressed)
2) the "look forward" view (press NumPad 8)

I have learnt of another two forward views you can save head positions in!
If you combine forward left or forward right (7 or 9) with a rear view(2) you get view ahead positions that you can save. I have done this to "see" over the cowling left and right sides!


Kaybayray
My advice would be don't use the set trim <.> Use combat trim instead for generally flying around trim. If you find you are badly out of trim turn it on for a few seconds and then off again.
Set trim is not really that user friendly and I only use it rarely like when diving in from a long way out and just wanting to ease off stick pressure. If you are manouvering (i.e. moving any controls at all) set trim is really not helpful at all and so you will not find it working for you.

Autospeed trim (best for climbing) and level trim are perhaps the most useful but remember both are more than trims, they are autopilot types of modes and continually adjust until the steady climb speed or level flight is achieved. You can switch them off two ways. The first is to fight the trim and overcome it with control movement. But the best way is to switch it off by pressing any auto trim, as these trims toggle on and off. The light on the instrument panel even lets you know what trim you have on (if any).
yellow - auto level .  or  red - Auto speed(climb) or no light no auto trim!

[KayBayRay]

Thanks All

Great info and advice from everybody  

I will check this stuff out and make these changes. Sounds like it will take care of things pretty good.


Later,

kaybayray