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Airfield Landing Trim Issue


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Sorry to bring up this highly beat up subject - again - but I'm not seeing anything that's helpful for my situation. 

So I'm running some airfield landing training missions to learn how to eventually land on a carrier.  I'm spawning in  the Persian Gulf 10 nm out from the runway about 3000 ft AGL, and 300 kts.  I'm following tutorials trying to achieve an AoA around 8, in the bracket, with fvi aimed at end of runway, with orange on-speed indicator and on the glideslope 3.5  degrees.  I'm using throttle for altitude, and trim for attitude - or at least I'm trying to.  I've made at least 150 attempts (with a lot of cussing) over the past week and achieved success maybe twice, I couldn't even tell you why that happened.  

I'm using throttle judiciously I think, but I'm having issues with trim.  I can hammer on repeatedly or hold the trim button down/up to very little effect.  I don't have that issue with the A10-C so I do not believe it's hardware.  So because of that I'm having issues managing a steady and accurate glideslope and attitude  I'm wondering if there is some aircraft state in which trim cannot really be adjusted.  Here's the sequence I'm trying. 

Spawning as mentioned above Lower throttle to reduce speed, engage speed brake.  250kts, gear down.  225 flaps down full  During this time I'm keeping the velocity indicator pretty much at end of runway with the stick while everything is settling down with all the changes.  When I get below 180 I start letting go of the stick to see where I am in terms of trim. and then I start adjusting that and the throttle to maintain glideslope and AOA.  And things quickly go wrong since I'm unable to change the trim quickly enough- most of the time.  It either over does it or under - and sometimes there's a delay - so I'm pounding on trim for 5 seconds with no movement, then all of a sudden I have 5 degrees change

I have TM Warthog stick and throttle quadrant, I've checked the mapping to make sure I do not have duplicates.  Also if I use keyboard trim commands it performs just fine - but I don't have three hands so this doesn't work very well.  Trim works predictably with the A10-C in DCS and in X-Plane 11 aircraft.  I do notice that extremely small movements of the throttle have very large effects which is not helpful in this complex situation which requires nuanced control surface movement. 

I know this subject has appeared repeatedly - so if you can direct me to a post that explains this I would appreciate it.  Otherwise any ideas you have in this regard would be appreciated.  I'm not a newbie - I've been doing DCS and other flight sims for many years - so this is very frustrating.  

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Ok - I finally figured it out.  After I tuned the throttle/thrust axis to be a little less sensitive in the typical throttle range for landings I am able to nail the landing pretty much every time.  I used the user curve settings from forum posts from a couple of years ago.  0 8 15 22 30 39 48 59 71 85 100.  Works like a charm.  It's really interesting how much small thrust variations affect the ability to trim properly.  


Edited by zippydoda
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  • 2 months later...

I am glad you got it working. One suggestion I have is wait until down to 180-190 to go full flaps. I find that anything above that causes the plane to head for the sky which I have to counter w/ the stick. If you wait til 180-190 the flaps slow the plane quickly (like one would expect) and near zero heading to the sky. 

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  • 4 weeks later...

Don't use the stick to keep the velocity vector on the threshold. Use the throttle to do that.  More throttle moves the VV further down the runway.  Less throttle moves it closer.  

While you're at it, you might try using the rudder to regulate alignment.  Leave the stick alone.  

Try flying the pattern.  If you have yourself all set up and trimmed out in level flight on the downwind, the thing will pretty much land itself.  

Ryzen 5600X (stock), GBX570, 32Gb RAM, AMD 6900XT (reference), G2, WInwing Orion HOTAS, T-flight rudder

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On 4/11/2022 at 1:32 PM, DeltaMike said:

While you're at it, you might try using the rudder to regulate alignment.  Leave the stick alone.

I respectfully disagree. You will definitely have to use the stick for aileron in a Case I, so better learn early on to change bank without interfering in pitch.

And generally speaking, low speed regime is never the best environment to play with the rudder anyways... My 2 cent at least...


Edited by Razor18
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That's the best time to use the rudder, when you're flying at high AoA.  That's when the rudder actually does something.  

Problem with banking is, you lose lift.   You see this when refueling, for example.  No matter how gently you ease the stick over, you wind up low and slow when you're done.  A teeny touch of rudder might work better.  Granted, you are correct, you still have to mind the stick due to dihedral effect.  You'll get a little roll.  Point being, it's a little.

When you're flying the pattern, you're fairly close to stalling at any given time.  You really don't want to lose much lift if you can help it.   If you do, pulling on the stick won't get it back.  Quite the opposite usually.  

So, when you're turning to final, you have the option to flatten out your bank angle a little and use some rudder to make up the difference.  When you're on final, as when you're refueling, you have the option to use a little rudder to get yourself lined up (and, when there's a cross wind, to keep yourself that way).

I guess you don't have to use the rudder if you don't want to.  I'll say this though, if it takes more than a little rudder to get yourself lined up on final, you probably made a mistake two turns ago.  


Edited by DeltaMike

Ryzen 5600X (stock), GBX570, 32Gb RAM, AMD 6900XT (reference), G2, WInwing Orion HOTAS, T-flight rudder

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