How exactly does trimming work?

[Bullett00th]

I've only flown the Yak and the Mig so far but both show this weird pitch trimming behavior, where by default the plane's nose is diving slightly, so I adjust pitch trimming to compensate for it and move perfectly to the horizon.

However after a time I get the reverse effect where the nose is constantly going up, even if I reset trimming to default, so I readjust.

I thought it was a speed-related thing but it happens regardless. Can anyone explain please?

[heartc]

Not too familiar with the Yak and MiG myself, but it should be the same for all planes. You are indeed trimming for speed (it may feel like one is trimming for nose position, and in combat, with rapidly changing speeds, you are de facto trimming the nose, but what you are really doing in terms of aerodynamics is trimming for speed). That means whatever trim you set, it is a trim that will result in a certain airspeed and the nose will adjust itself to "achieve" and hold this airspeed. Depending on how far out you trim of the current speed, that is taking place slowly and will oscillate above and below this trimmed airspeed until the plane has stabilized onto the trimmed airspeed (I'm just talking about the aerodynamics now, not what is good practice - in practice, you should of course fly the airplane via with the stick and throttle to the parameters you want and then use trim to remove stick force or have the control in neutral position, unless you are making only small changes to fine adjust trim).

This also means that if you trimmed for a certain airspeed and achieved level flight, once you increase power, even slightly, or close radiators etc, the nose will go up to hold the currently trimmed for airspeed. Resetting trimming to default shouldn't actually cross your mind, since that is a rather gamey function and not actually helpful. If you find your nose rising, you should simply trim against it to adjust for whatever made your plane wanting to go faster, instead of going all the way back to default and then readjusting to the proper position, which was much closer to the one you already had.

[-OrLoK- Слава Україн]

as above but shorter.

Trimming is something one adjusts constantly in most aircraft during flight.

[heartc]

How exactly does trimming work?

Trimming is something one adjusts constantly in most aircraft during flight.

It is certainly shorter though.

[martin77]

a plane never fly straight. You trim to a certain airspeed.
Fly you faster, then the wings have more effect and the nose go up.
Fly you slower, the opposite efect set in.

[Bullett00th]

Originally posted by martin77:

a plane never fly straight. You trim to a certain airspeed.
Fly you faster, then the wings have more effect and the nose go up.
Fly you slower, the opposite efect set in.

this is my understanding, I just get confused when after a prolonged flight trimming 'leaves' the effect of higher speeds even at lower speeds and when resetting trimming to default.

was wondering if it's a bug or a mechanic

[Disarray]

It is speed related. As you change speed the lift/drag forces change and this precipitates a change in your nose attitude. It is a very dynamic system at play. If you find yourself changing trim all the time don't worry. You have to, unless you are OK with the change that is occurring.

[martin77]

A good thing is
-trim the plane for cruising and flying to a target point
-trim the plane before a combat
-trim before landing
this are tthe 3 times i change the trim, you dont need trim all the time

[Bullett00th]

Originally posted by Disarray:

It is speed related. As you change speed the lift/drag forces change and this precipitates a change in your nose attitude. It is a very dynamic system at play. If you find yourself changing trim all the time don't worry. You have to, unless you are OK with the change that is occurring.

this put my mind at ease, thank you

what about sideways trimming though? I've flown Yak, Lagg and Mig, and none seem to have any affect when I change the setting. Is it available on other planes?

[Frenchy56]

Originally posted by Bullett00th:

Originally posted by Disarray:

It is speed related. As you change speed the lift/drag forces change and this precipitates a change in your nose attitude. It is a very dynamic system at play. If you find yourself changing trim all the time don't worry. You have to, unless you are OK with the change that is occurring.

this put my mind at ease, thank you

what about sideways trimming though? I've flown Yak, Lagg and Mig, and none seem to have any affect when I change the setting. Is it available on other planes?

Only the La-5, P-47 and P-40 have yaw trimming as fighters go. Bombers should all have it.
As far as yaw is concerned, all you have to do is simply to put the black ball between the two lines.

[Disarray]

You also get adjustable roll trim in some of the US fighters, the P-47 is the only one I can say with confidence has it for sure. Other fighters have roll trim as well, but it is fixed. In reality the trimmers could be adjusted by ground crews but in game they don't move at all. Generally they are set for cruising speeds. The 109's for example are generally trimmed for wings level flight at around 300 kph. Bombers and attackers generally come with a full suite of trimmers because they are big and heavy and it would be a real pain in the ass, and other body parts I'm sure, to fight the controls all the way to target and back.

[Bullett00th]

Got it, thanks.

I was wondering because I set pitch trimming on up and down of the small thumb directional thingie on my joystick and was wondering if left and right were worth binding to yaw trimming or something else

[trooperrob]

I believe weight and centre of gravity will also affect trim, ( if modelled), wind direction and altitude etc as well. fuel use will probably affect it.

[Bullett00th]

Originally posted by trooperrob:

fuel use will probably affect it.

hmm, didn't think of that. does the game actually account for fuel weight? I know it does for ammo

[Disarray]

The game does take fuel weight into account for some aspects of flight. Maximum gross take off weight is modeled for example, just try getting an HE 111 off the ground with a full bomb load and full tanks and enjoy the hilarity that ensues. Fuel weight is also modeled as it concerns agility, top speed, acceleration, and climb rate. I'm not sure if CG is affected by fuel load but given the attention to detail they have put into weights and their effects of performance I would not be shocked to learn that it is.