Trim help

[Pete Wilcox]

I've realized I have been relying on autopilot too much. Can someone give me a little instruction on proper ways to trim an airplane? It seems I am either up or down and can't find a level flight.

Thanks

[Jethro VH-JET]

Hey Pete

That would depend upon wether you wanted a real world trim setup or a comfortable simulated experience, and depending wether you fly large tubes or light aircraft with a yoke or joystick.

As I'm not a real pilot and use a joystick for axis, flaps and trim, I like to have a slight nose down attitude ( maybe one notch on the trim beyond neutral balance )  and have a little backpressure on the stick. I usually setup elevator trim before takeoff neutral, and arrive therafter at the top of the climb, level off for (Cruise), then settle the aircraft to begin trim. Otherwise I just set the trim to the point of level flight according to the HSI or attitude indicator.

Real pilots will have a better answer than mine I am sure, but for simming the aircraft seems more stable and responsive with some backpressure. Would definitely be interested what the RW pilots can explain about trimming the aircraft.

 

Cheers Jeff

[Andrew 737]

In a C172 I will 'select' the attitude, 'hold the atitude' and then trim away the forces on the control column. This can't be done using FSX trim and a centre sprung yoke - with a centre sprung yoke you trim the yoke to centre and not trim the forces away. Go and have a read over at the FSForce website - brilliant explanation there.

[Wolter van der Spoel]

if my memory serves me correctly you can trim the aircraft by disabling the num lock on the number keypad and then using the 1 and 7 you can trim up or down or the other way around

[Mickey]

It is pretty easy to trimm a plane to fly it straight and level at a certain speed means trimming is speed dependent. The faster you fly the more you have to trimm nose down and vice versa.

 

On my keyboard i have the keys K and H for elevator trimm and on my joystick too. I highly recommend you setup your joystick with trimm commands. 

 

Now lets asume you fly straight and level and you have to keep the nose up then you gonna have to trimm so as to neutralize the force and to bring the joystick back to center position. Most probably you will fly then slow In flight sim you gonna have to look at the ADI or out of the window (VM weather required) to see how the aircraft reacts. In real life you just have to "feel" the plane to know how you have to trimm.

 

Trimming means to bring all forces acting on the aircrafts flight controls to an equilibrium so that the pilot dont have to give constant control inputs.

 

If you fly an Airbus 318 up to 380 you dont need to trimm as these tubes have auto trimm (pretty lame) Other tubes like the Boeings need manual trimming while manual flying.

[Maurice_King]

Climb to cruise Alt then once established at Cruise Alt throttle back and tune you CHT EGT at cruise and only then even think about trimming. AFTER your airspeed has settled and your happy with your power settings you can then trim forward or back as is needed to maintain a constant speed.  If your speed is constant then your attitude will be constant and thus your Altitude. DON"T try to chase your tail as you will just constantly porpoise 

 

This method will apply to most GA and even light commercials

[Pete Wilcox]

Thanks for all the suggestions. I did a better job yesterday of keeping it trimmed. I can see though trimming deserves a higher priority on button selection whether you are using a stick or a yoke. I think I was getting a constant porpoise because I kept over trimming each time. It's more subtle than I thought. I wasn't giving the airplane enough time to react to a slight amount of trim. Seems to be a bit of an art.

[John Dow]

It is, and it's harder in the sim than in real life.  Mostly in the real world a 172 will remain level and stay at the same altitude reasonably quickly after trimming, until conditions change, like balance or turbulence.  In the sim I find that even when trimmed the aircraft will change to a climb or descent at the drop of a hat.  Maybe it's because I have real weather nortmally and have ind gusts set up in FSUIPC.  Anyway it means I actually have to fly the aircraft not sit and twiddle thumbs so it's probably a good thing.

[Mickey]

It is, and it's harder in the sim than in real life.  Mostly in the real world a 172 will remain level and stay at the same altitude reasonably quickly after trimming, until conditions change, like balance or turbulence.  In the sim I find that even when trimmed the aircraft will change to a climb or descent at the drop of a hat.  Maybe it's because I have real weather nortmally and have ind gusts set up in FSUIPC.  Anyway it means I actually have to fly the aircraft not sit and twiddle thumbs so it's probably a good thing.

 

I can speak only for F-33A B-58 (Carenados are perfoming quite well in the sim) CRJ 2/7/9 and EMJ 190. The Beeches are pretty stable after trimmed out. CRJ are a pain in terms of trimming, there you have to find the sweet spot -for 30 sec or so there after trimming is required again!!! EMJ 190 is rock stable, one or two trimm inputs, done

 

In the sim it is like John said but i think it is a global simulator thing. I havent flown a sim (PC nor full flight nor fixed base) that could simulate trimm situations as they occur in real life. 

 

Watch and know your pitch and power values at least when you are flying NON HUGS (Head Up Guidance System) aircraft that is all you need to control you will automatically hold altitude, attitude and speed.

[teecee]

I had one of my Saitek buttons on the X52Pro set for trim..worked fine but a bit touchy, so I bought the Saitek trim wheel (around USD50)..Magic, and much closer to RL flying.. Teecee.

[Guest M31]

As above, invest in the Saitek trim wheel, its not too expensive and after the other basic controllers like HOTAS or yoke and throttle and rudders is one of the best hardware controller investments you can make, the Saitek Multi Panel has a little trim wheel built in in but is not nearly as effective as the stand alone Saitek trim device IMHO.

[Pete Wilcox]

I'll check it out.  My space right now is limited.  The way the scenery is improving by leaps and bounds makes you want as much realism in the controls also.

 

Thanks.

[Todd Harrell]

I use the rocker switch next to the hat switch on my Saitek yoke as my trim botton. Trim is your friend. It takes time to figure out how much you need, which comes with experience. I have found you don't need as much as you think. Once you do figure it out, it'll become your best friend, especially during landings.

Todd

[Snave]

Trim is easy to use, once you figure out that the key presses are time sensitive - hold them longer, trim moves faster.

 

Armed with this it's just a question of setting up a joystick or yoke button to replicate the buttons and things get simpler - press and hold for faster, greater adjustment; blip, blip,blip for finite, small increments.

[Pete Wilcox]

I use the CH Products yoke because it seems to have less tension than the Saitek..  And now I see why people also want pedals. 

 

So when you get in a situation where you've reached altitude and when the yoke springs back to center it keeps elevating the aircraft that's when you need to trim.  Right?

[Todd Harrell]

Pete, yes, that is certainly a good time to use it. I also use trim during takeoff to maintain my rate of climb. I use it entering turns as you need some back pressure to maintain level flight in turns. Lastly, I use it during landing, as a well trimmed plane will maintain a nice descent rate without you having to constantly fight it. I personally use trim a lot, pretty much in every phase of flight. Based on your comment, Pete, I think you have the just of it.

Todd