Using electric trim

new121plt

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They used to say there was no such thing as a stupid question in aviation, but here's my attempt:

I'm new to 121 flying and the Dornier Jet. The Dornier has no "manual" trim wheel, just an electric trim thumb control. (PS after seeing the B737 and B727 cabins, I kind of hoped that all big airplanes would have big manual trim wheels, but I guess Dornier wants to save money.)

Here's the deal - on climbout and hand flying the Dornier the captain asked me what I was doing with the pitch control of the airplane. Specifically he wanted to know what I was doing with the trim. I said I was pitching to a desired number, in this case 12 degrees nose up and then trimming to relieve the pressure off my hand. He then asked where I learnt to fly and then scolded me saying that I should be flying by making the trim lift the nose to the value.

I've never flown a plane with as much power as the Dornier - 12,000 lbs of thrust for a 34,000lb airplane. I guess my trim style/technique is too rough. What do I do? What do you guys do?

How do you make a smooth ride with a fairly powerful and quick aircraft especially using only an electric trim button to accomplish it?

After the captain pointed this out I became completely ham-handed at controlling the airplane. I sure miss being able to drop my other hand down and grab a trim wheel so that I can "feel" the weight of the airplane. Any input would be appreciated.

PS. The Dornier has a fair number of pitch changes in the takeoff and initial climb out. On rotation, you are artifically limited to 7 degrees nose up to avoid immediate tail strike, then the airplane needs about 10-12 degrees nose up to accomplish a nice on-speed climb. BUT, when you retract the gear, the airplane pitches up and at a thousand feet we retract the flaps and the airplane pitches down.

In my view and having flown a lot of Centurian's and Seneca's in the past (fairly heavy feeling GA airplanes) I used to not bother with a lot of trim between rotation and the thousand foot flap retraction. I would just set the trims for takeoff which is slightly nose up. Then on rotation I would control pitch momentarily for the seven degrees. Call for Gear Up, The plane would pitch up and I would apply a small down force in keeping the plane at around 10 degrees then at a thousand feet I would call for flaps up and absorb all the pitch change in my hands until comfortable at 10-12-15 nose up whatever I needed and then would trim the force away. This would create anywhere from 20 pounds of down force to 40 pounds of up force in my hands until the trim could assist. And remember that all of this is happening in the six to seven seconds that the plane requires to climb out.

All comments except for "Use the autopilot!" and "What's hand flying?" are appreciated.
 

Boeingman

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Your technique of trimming to relieve pressure sounds fine to me. Unless there is something in your FOM that this guy is talking about. If there is not it sounds like he is trying to get you to use his "technique".

Does your company have a profesional standards committee? If at all possible, keep it from management and let the union handle this cowboy.
 

Mickey757

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If the Capt that you flew with wanted you to fly the a/c with the trim instead of as you were correctly doing ( i.e. set pitch, than trim out the control forces ) Maybe you should ask him/her where they learned to fly?
Guaranteed they never flew a big airplane!;)
 

flydog

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Most jets can be very heavy in pitch particularly when making large speed and/or configuration changes. In light planes there is nothing wrong with trimming to relieve the pressure after things have settled out but in some jets this may be difficult to do so I use a combination of stick force and trim to level off.

The Westwind is in fact so heavy in pitch that if the trim were imporperly set at full nose down on takeoff both pilots together wouldnt have enough strength to rotate the airplane.

Use whatever method you are happy with just dont be ham handed with the electric trim. Keep in mind there are passengers in the back and you dont want to put them on the roof on a level off. I think its far worse to fly the airplane with the trim as this Captain is doing than to trim it off the pressure after everything is settled in but thats just an opinion.

I typically hand fly all the way up to altitude and leaving altitude and use the autopilot only in cruise unless its a high workload environment
 

rudderdog

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It's a combination. In heavy airplanes, when changing flap settings and making large airspeed/pitch changes I tend to trim during the pitch change. If you know the airplane well you should be able to anticipate much of the change and trim some at the same time as the airspeed/pitch change or flap setting change. If you let the trim HELP you make the change and constantly decrease the amount of force your applying, it will make for a smooth transition. Knowing how much trim it will take and applying it at the correct rate is key. Then you can do your hands off thing to make small changes.:cool:
 

AWACoff

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I came from flying a Brasilia (which had manual and electric trim) to the Dork prop. I only got 70 or 80 hours in the Dork before furlough but flying with electric trim only just takes a little practice. You'll be "Smoov Dawg" before you know it. I always used the trim to relieve control pressure. I'm not sure what that captain was smoking. Refer to the thread titled "Flying with old salty dogs". That's not quite the title but it's close enough.
 

FlyinBrian

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In the Saab, used control and trim simultaneously, especially during configuration changes. Every time I said "Flaps 15", I knew I had to push fairly aggressively and lay on the trim. I would still say this is more akin to trimming out control force rather than flying with trim. You're just trimming out the control force at the same time you're putting in the control input. Never flown a DoJet, so maybe he knows something I don't, but I'd say your techniques is more standard.
 

bobbysamd

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Trim use

Your question is not in the least bit stupid. Your captain, in my .02, is stupid. Just use the trim as you've done for your 3500 hours. Probably, as mentioned above and absent FOM direction, it boils down to technique.

You have plenty of experience flying and you didn't get where you are by not knowing how to use the trim. You've flown lots of airplanes, I'm sure; the Dork is just another airplane to fly and to get onto. It sounds like you have a handle on the pitch and trim chart.

I have heard of using back electric trim only to flare in some airplanes. I dunno about that one. Wasn't there some DC-8 freight accident many years ago in which the Captain was using electric trim to flare the airplane?
 

DC9stick

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In any airplane if you are applying 40 lb of pressure to the yoke you should be trimming. I personally like to have the airplane in trim at all times. If you are pushing or pulling you should be trimming, except landing. Excessive nose up trim while landing may cause a tail strike, reverser drag (MD-80) or an uncontrollable pitch up in the event of a go around.

All that said if you are comfortable with all that P&P and the A/C is not porposing it's an acceptable technique. As long as you are following procedure, technique is at the individuals discretion.
 

Tref

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Hi new121plt,

It's so annoying when people fly off the handle when they're wrong! If you try trimming a larger jet his way you'll always be overtrimming. His technique might work for him on that airplane, but your technique will work for everyone on pretty much all airplanes.

And remember "the only stupid aviation question is the one that doesn't get asked." Corny but true!
 

new121plt

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Thanks for the replies - I didn't expect so many.

Don't be too hard on the captain - he was a very smooth operator, he just didn't know how to communicate well. I'm still new to this stuff and I was just doubting my own flying ability / knowledge.
 
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