Takeoff Trim Setting

Hey Guys...

This may sound like a stupid question but in the interest of doing things right...What is the correct procedure for setting Takeoff Trim?

Do I simply look to see if it lights up and goes out when I push the button?

Am I supposed to hold the button until it stays lit?

What do I do if it doesnt stay lit?

Thanks in advance

I hold the button down for over 2 seconds , why , cuz I read somewhere thats what to do . Im not sure if it really matters to be honest . Its just what I do .

The light isnt supposed to stay lit .

Hope this helps :)

All you have todo is hold the button until the light illuminates.

The light won't stay illuminated.

All you have todo is hold the button until the light illuminates.

 

The light won't stay illuminated.

Thanks Guys... !

To see what the T-O trim button does, try the following:

when cold-starting the plane, wait till the engines are spooled up and hydraulic pressure is present, then trim the plane extensively to one direction, left-right-up-down doesnt matter. Just observe the stick.

Then press and hold the trim button, and voila: the stick centers magically!!

So what the trim button does is, it recenters all trim inputs, so you have the "default" trim setting at take off.

Hey Guys...

 

This may sound like a stupid question but in the interest of doing things right...What is the correct procedure for setting Takeoff Trim?

 

Do I simply look to see if it lights up and goes out when I push the button?

Am I supposed to hold the button until it stays lit?

What do I do if it doesnt stay lit?

 

Thanks in advance

Takeoff trim means resetting the trim. You don't have to hold it down or anything. a single press is sufficient. Be warned that the aircraft will veer to the heavier loaded wing side during roll and takeoff, so trim the rudder 2 taps opposite the load, and the wing opposite the load to 1 tap, both after pressing takeoff trim, and not before. Rudder trim helps also with being centered on the RWY at FMP.

@Noc_orthodontist:

It's not correct, you have to hold the button until the take off trim light illuminates. Otherwise the trim settings are not fully reset!!

Observe your stick when pressing the button. You will see what I mean.

On the ground, at startup, you will not have to hold the button for long because the trim settings are default.

But if you have to rearm or refuel and take off again, you will see that it takes much longer for the light to illuminate, because you have trimmed the aircraft a lot and the settings are off.

Takeoff trim means resetting the trim.

Right!

You don't have to hold it down or anything. a single press is sufficient.

Wrong!

...or let's say (to alleviate it a little):

It depends on in which Trim-state you are.

If you don't have any trim applied, - something that is quiet usual to the ideal simulation-world after a start-up -, a single key-press is sure enough because you are always having a perfectly neutral-trimmed aircraft.

But,...

have a look at this video to fully understand what Takeoff trim does to your stick.

I first trim to max left and back.

Than you can see that a single short press will not bring it to "Takeoff-Trim"...

I have to press-and hold it as long it takes to bring it back and the green "Takeoff-Trim" indicator is lit.(same apply to a non FFB controller - but off course you will see no movement at the real stick - so you have to watch the indicator light)

Conclusion:

It is most of the time unlikely that you will have a unbalanced trimmed aircraft in the simulation after a start-up , so a single key-press is sufficient ...(as long you are sure that you don't touched the trim hat before takeoff).

But in the Real cockpit you never know what might happened.

...be it that the crew-chief made some preparations and undauntedly touched the trim-hat to have some fun with you...

Or you did it your self while start-up.

So you engage the Takeoff-Trim every time before leaving the ground (until green indicator is lit) to be sure that your control surfaces are in a neutral position to prevent yourself from nasty surprises as soon your gears are in the air.

edit:

Norrised by Timmay! - (I have to write quicker!:P)

Nice, thanks for the explanation. I assume it can be used in-flight to reset your trim as well.

I assume it can be used in-flight to reset your trim as well.

This is very interesting. Especially, because it is called "Takeoff Trim". Is it possible/advisable to use it while airborne?

Possible? Yes. Advisable? Definitely not.

Possible? Yes. Advisable? Definitely not.

That's the most fun button to press while airborn! :thumbup:

That's the most fun button to press while airborn! :thumbup:

Should I try it? I have a certain kb combination assigned, which will reset trim. So haven't tried airborn Takeoff Trim so far.

All takeoff trim does is zero out flight controls and can be used anytime.

Should I try it? I have a certain kb combination assigned, which will reset trim. So haven't tried airborn Takeoff Trim so far.

For best effect, try it just before landing.:D

All takeoff trim does is zero out flight controls and can be used anytime.

Thanks for the reply, paulrkii. So it is a safe procedure, even if airborne?

"can be used anytime" really means anytime.

It will remove all trim-inputs you have applied.

nothing more - nothing less

And you will quickly see if this is a good bad/idea, - normally it will result in a slight change in your flight-pass without a sudden "bang".

Should I try it?

...Do or do not… there is no try !

Should I try it? I have a certain kb combination assigned, which will reset trim. So haven't tried airborn Takeoff Trim so far.

Keep pressing it until you get the surprise package! I'm sure it's there somwhere :thumbup:

@Noc_orthodontist:

 

It's not correct, you have to hold the button until the take off trim light illuminates. Otherwise the trim settings are not fully reset!!

 

Observe your stick when pressing the button. You will see what I mean.

 

On the ground, at startup, you will not have to hold the button for long because the trim settings are default.

 

But if you have to rearm or refuel and take off again, you will see that it takes much longer for the light to illuminate, because you have trimmed the aircraft a lot and the settings are off.

Right!

 

Wrong!

 

...or let's say (to alleviate it a little):

It depends on in which Trim-state you are.

If you don't have any trim applied, - something that is quiet usual to the ideal simulation-world after a start-up -, a single key-press is sure enough because you are always having a perfectly neutral-trimmed aircraft.

 

But,...

 

have a look at this video to fully understand what Takeoff trim does to your stick.

 

I first trim to max left and back.

Than you can see that a single short press will not bring it to "Takeoff-Trim"...

I have to press-and hold it as long it takes to bring it back and the green "Takeoff-Trim" indicator is lit.(same apply to a non FFB controller - but off course you will see no movement at the real stick - so you have to watch the indicator light)

 

Conclusion:

It is most of the time unlikely that you will have a unbalanced trimmed aircraft in the simulation after a start-up , so a single key-press is sufficient ...(as long you are sure that you don't touched the trim hat before takeoff).

 

But in the Real cockpit you never know what might happened.

...be it that the crew-chief made some preparations and undauntedly touched the trim-hat to have some fun with you...

Or you did it your self while start-up.

 

So you engage the Takeoff-Trim every time before leaving the ground (until green indicator is lit) to be sure that your control surfaces are in a neutral position to prevent yourself from nasty surprises as soon your gears are in the air.

 

edit:

Norrised by Timmay! - (I have to write quicker!:P)

I stand corrected, gentlemen! Thanks to Peter for the quick illustration.:thumbup:

All takeoff trim does is zero out flight controls and can be used anytime.

So what is the practical difference between the fictional game's function of resetting trim and the actual A-10 Trim T/O button?

They both set al surfaces to their initial position, what else?

This is very interesting. Especially, because it is called "Takeoff Trim". Is it possible/advisable to use it while airborne?

Hmmm! I guess we can all try it and see what happens. :music_whistling:

It may turn out that it requires weight on the gear and is thus it would be inoperative in the air.

OR ...... it may work in the air, but beware! If the aircraft has been trimmed away from the default setting to maintain level flight, setting it back to default neutral will put the aircraft out of trim, with potentially interesting results.

I shall try it out next flight just for the fun of it :D

Sorry for the bump.

 

So what is the practical difference between the fictional game's function of resetting trim and the actual A-10 Trim T/O button?

 

They both set al surfaces to their initial position, what else?

I would think exactly that? There's no doubt lots of mechanical and hydraulic what not happening inside the plane, and it would be interesting to see the design of how the system resets to exactly zero, but otherwise I think that there isn't likely much more to it

The A-10 isn't a complicated airplane when it comes down to it. For the maintainers, probably a lot more complicated than for the pilot, but still, relatively straight forward I think. However, if there is more to it, I'd love to know.

I would think exactly that? There's no doubt lots of mechanical and hydraulic what not happening inside the plane, and it would be interesting to see the design of how the system resets to exactly zero, but otherwise I think that there isn't likely much more to it

 

The A-10 isn't a complicated airplane when it comes down to it. .

Agreed. From elsewhere on the forum I gathered that 'take-off trim' could be read as 'take off trim' i.e. set trim settings to zero or neutral displacement. It certainly seems to be the case from my experience just now:

Altitude 2,500 ft, speed 280 kts, no armaments loaded and 60% fuel. No auto-pilot engaged and trimmed to fly level 'hands-off'. Pressing the trim button for 3 to 5 seconds, with no HOTAS, produced an immediate nose up with a definite roll to the right. Hands back on and regained 2,500 ft and re-trimmed to fly 'hands off'. Autopilot engaged and then trim button pressed as previously. There was an obvious trim change which the autopilot countered with a minimal altitude and minimal roll change before returning to wings level and 2,500 ft. When the autopilot was then disengaged the aircraft imediately reacted in the same way as when the trim button reset had been pressed with no auto-pilot engaged.

It would not be surprising to find the real world aircraft behaving in the same way, as it would then be the case of the KISS principle at work. :D

It would not be surprising to find the real world aircraft behaving in the same way, as it would then be the case of the KISS principle at work. :D

KISS has always been a favourite concept of those concerned with designing robust systems capable of surviving and even functioning after being punctured with lots of high velocity chunks of metal. :thumbup:

Trim T/O does indeed not do anything fancy. When held, the plane slowly goes back to doing it's own thing, no radical changes.

Still, what is the difference between Trim T/O and trim reset? And why do we need the trim reset function if Trim T/O does the same thing?