Trim down vs. stick down?

chemgeek said:
It is much more difficult to precisely control the aircraft for long when it is not neutrally trimmed. You should normally always trim the aircraft to maintain the current flight speed and regime (level flight climb, descent) with no pressure on the controls. That way, if you release pressure you know what the plane will do, and if you feel pressure you know you are deviating from the current flight regime. Deploying flaps will change the required elevator position to maintain the current flight regime, so you should trim out that change. For example deploying flaps on my AA5 on downwind will cause a nose down pitch which is trimmed out with a short roll of the trim wheel nose up. I don't want to have to hold nose up pressure all the way down final, and have no good feel for the landing flare pull required when that time comes. Use your trim to neutralize control forces and give you consistent feel for the landing flare.
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I like all you wrote, but unless I’m mistaken isn’t the OP asking more about just trimming “in anticipation”?
Sort of like skipping the step where you use the stick/yoke to get the right airspeed, and then trim to take pressure off? I could see this being a thing a pilot might do after years flying the same plane, but I’m being taught to do it as you say, control the stick, trim off pressure.

I don’t see a real advantage to skipping the manual adjustment, at this point in my training. I did find the interesting (luvflyin wrote) idea of trimming so you have slight back pressure, but again, at this stage for me I’m gong by the “book” as I have learned it.
Was explicitly pointed out to never use the elevator to fly, just to relieve pressure.

As for “overthinking it” as some mention, it’s what we students do. There is so much to take in, and any given area of flying we are trying to put the separate peices together, so we overthink. I am guessing a lot of experienced pilots have forgotten how much they probably did this too, it’s natural.
 
Both Approaches and Landings should involve minimum effort by the pilot. Every time you change a configuration or power setting trim the plane.
 
Clip4 said:
Both Approaches and Landings should involve minimum effort by the pilot. Every time you change a configuration or power setting trim the plane.
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Bingo, this is what I did today. 25+ hours 'flying the plane because trim doesn't fly the plane' is what I was originally taught. For the longest time trimming was forced, never second nature.
 
LongRoadBob said:
I like all you wrote, but unless I’m mistaken isn’t the OP asking more about just trimming “in anticipation”?
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Your observation is mostly on track.

Example, I pull back to 1600RPM on downwind since that's "usually about right" and then I put in flap that is "usually about right: and I trim "about the usual amount." Then I adjust each of those as needed. (usually RPM)
 
Wow guys, I really appreciate all the thoughts and advice you put into my question! Very enlightening, and your input will be put to good use.

And LongRoadBob, thanks for confirming that I'm not totally insane for "over thinking it". While I do agree that in the long run, for more experienced pilots, over thinking could get in the way of proper flying, as a student I try to dissect every little bit of flying until I feel confident that something makes total sense.
 
Mooney Fan said:
What's missing here is what are you doing with the power????
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I've been doing it like this: power almost to idle, about 1700, carb heat during the base leg, flaps opposite numbers followed by two throws trim. Then turn final, cut power.
 
Sazzy said:
I've been doing it like this: power almost to idle, about 1700, carb heat during the base leg, flaps opposite numbers followed by two throws trim. Then turn final, cut power.
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So your stick down (instead of trim down) is in response to flap deployment? Not familiar with your plane. A power reduction and flaps in my plane requires trim up if using the appropriate amount of power.
 
Well no, that's what I was curious about. I am being taught to use the trim, but I had read a few things that contradicted (I am now learning erroneously) using trim at all and simply pushing stick forward. Probably just a couple bad articles. That's what my initial question was about, just to see what other pilots felt about that. But you're right about what you said, I'm seeing now.
 
Mooney Fan said:
So your stick down (instead of trim down) is in response to flap deployment? Not familiar with your plane. A power reduction and flaps in my plane requires trim up if using the appropriate amount of power.
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She's flying a high wing, you're flying a low wing.
 
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Sazzy said:
Well no, that's what I was curious about. I am being taught to use the trim, but I had read a few things that contradicted (I am now learning erroneously) using trim at all and simply pushing stick forward. That's what my initial question was about, just to see what other pilots felt about that. But you're right about what you said, I'm seeing now.
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I do that when descending from altitude with no power adjustments. Curious, how does your CFI teach slow flight? Anyway, if your reducing power and it starts your descent, then flaps...you are now trimming in response to that configuration change. And as I said before, in my plane that requires pitch 'up' to relieve control pressure. Power controls altitude, pitch controls airspeed. You'll get it
 
Honestly Mooney, the last few times I've flown, it's been too damn windy for any slow flight training to be constructive LOL. I did do a good amount of slow flight training at my previous airport (UGN), but since I've been at RAC, the changing weather vs. a light aircraft has not been very forgiving. My lessons have pretty much been centered around ground reference maneuvers and landings.
 
Not to mention, my current instructor is very different from my previous instructor. My previous instructor wouldnt take me up in winds such as 8G15KT in a c152. This guy didnt even question 14G23 in a LSA...that was a rough landing...
 
LongRoadBob said:
I like all you wrote, but unless I’m mistaken isn’t the OP asking more about just trimming “in anticipation”?
Sort of like skipping the step where you use the stick/yoke to get the right airspeed, and then trim to take pressure off? I could see this being a thing a pilot might do after years flying the same plane, but I’m being taught to do it as you say, control the stick, trim off pressure.

I don’t see a real advantage to skipping the manual adjustment, at this point in my training. I did find the interesting (luvflyin wrote) idea of trimming so you have slight back pressure, but again, at this stage for me I’m gong by the “book” as I have learned it.
Was explicitly pointed out to never use the elevator to fly, just to relieve pressure.

As for “overthinking it” as some mention, it’s what we students do. There is so much to take in, and any given area of flying we are trying to put the separate peices together, so we overthink. I am guessing a lot of experienced pilots have forgotten how much they probably did this too, it’s natural.
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Actually the OP asked if trimming after flap deployment was unnecessary. Most pilots would suggest it IS necessary for optimal aircraft control. Deploy flaps, then trim out to neutral pressure. If you fly the same plane long enough, you will know almost exactly how much to roll the trim wheel to do this, but will always readjust as needed to trim out control pressure. When you pull the throttle to descend at final approach speed, you will trim again to the new speed. It will become instinctive...change flight speed...retrim. Makes maneuvering a whole lot easier. During my primary training, learning how to use the trim wheel properly was a revelation.
 
The thing I was suggesting is that since you are putting the flaps down while at the same time reducing your speed it's possible that the pitch up tendency is transitory, meaning the aircraft will be in trim again when you reach your final approach speed if you don't mess with the current setting. So rather than make two trim adjustments just push the stick forward until you've reached that speed and the force is no longer needed. I'm not familiar with the specific aircraft but that's probably what the articles you read are referring to. Right now you want to just follow your instructor's guidance, there is more than one way to go about this and eventually you'll be on your own and figure out which way you prefer.
 
Sazzy said:
Wow guys, I really appreciate all the thoughts and advice you put into my question! Very enlightening, and your input will be put to good use.

And LongRoadBob, thanks for confirming that I'm not totally insane for "over thinking it". While I do agree that in the long run, for more experienced pilots, over thinking could get in the way of proper flying, as a student I try to dissect every little bit of flying until I feel confident that something makes total sense.
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I know for sure I have a tendency to overthink. With flying, it goes into high gear. I experience that as a student there seems to be SOO much to learn. Even besides navigation, radio, just focusing on actually flying, taking off, landing the plane and doing maneuvers. I think one tends to think that this is something you have to get right, and there is concern that maybe one missed a crucial point. After time, I’m thinking, “yeah, there can be all kinds of variables too, with wind, etc,” but at the same time, you start also thinking “I’m diligent, it can’t be THIS hard as I’m feeling it is”. So far most of my reactions have been ok. In the end it is just to listen to the CFI. But with all the information out there, that does “overthink” or just goes into a lot of detail...points out things we haven’t yet been taught, yet. Having so much information on line is both good and bad at this stage.

I noticed after some hours, that I was starting to trim a lot more and it really, really made things a good deal easier. Fell into place.

chemgeek said:
Actually the OP asked if trimming after flap deployment was unnecessary. Most pilots would suggest it IS necessary for optimal aircraft control. Deploy flaps, then trim out to neutral pressure. If you fly the same plane long enough, you will know almost exactly how much to roll the trim wheel to do this, but will always readjust as needed to trim out control pressure. When you pull the throttle to descend at final approach speed, you will trim again to the new speed. It will become instinctive...change flight speed...retrim. Makes maneuvering a whole lot easier. During my primary training, learning how to use the trim wheel properly was a revelation.
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I see you are right. I misread, reading again I caught it. And what you are pointing out helped me a lot too...learning to trim first with “about right” in the ballpark trim, then fine trimming.
 
You should be retrimming the aircraft nearly constantly. Anytime you change airspeed or configuration you will need a trim change. It should become nearly automatic to trim out control pressures. In military training years ago the instructors would constantly say “Hands”. When they said that you were expected to hold both hands up so the instructor in the back seat could see them. The aircraft was expected to not move if correctly trimmed. If caught with the aircraft out of trim a below average grade in basic air work was the usual result. To many of those and you would be sent home!
Your instructor probably knows that flap extension requires about two turns of trim. You should fine tune that to keep the aircraft perfectly trimmed.
 
mryan75 said:
How far along in your training are you? I was taught similarly. It's a good rule of thumb for beginners. You will learn to fine-tune it more as you gain experience. Generally any time you make a power adjustment, you should be checking trim. Someone mentioned you should be able to fly hands off without the airspeed changing. Which is true. Remember, there are 3 keys to good landings:

1. Airspeed control.
2. Airspeed control.
3. Airspeed control.
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I would add an equally important 3 keys, especially if one ever wants to transition to a TW:

A: Directional Control
B: Directional Control
C: Directional Control

In a tricycle yea that’s may be secondary to airspeed, but if you drag your tail perfect airspeed with lousy Directional Control going to make for some hairy landings...
 
Another one here - you will fly better without backpressure on the yoke. Most airplanes require some retrimming on base and final. 81917 was a rare exception, but that aircraft is sadly long gone.
 
Some people are WAY too trim happy. Trim is there to relieve control pressures, not fly the airplane - especially in light aircraft. The degree to which you want nose up or down trim also varies from aircraft to aircraft. In the Tiger, slowing the plane down is something that takes practice. Because of that, most of my trimming comes on the approach to landing, not on the landing itself. I land it best with the trim a touch forward of neutral. In my friend's Arrow, I land best with trim about 1/3rd of the way nose down, sometimes more. The heavier back pressure needed actually helps keep you from pulling too hard and thunking it in.
 
Some pilots like to trim during the landing flare. Nothing wrong with that if it works for them, and in a nose-heavy aircraft it may help.

But the landing flare is the one phase of flight where I do NOT want to trim out control pressure - it’s the gradually increasing need for back pressure that helps me feel what’s going on with lift and energy, and helps me achieve a slow, mains first touchdown at or near stall speed. For me personally, trimming that pressure out would make landing harder, not easier. But to each their own.
 
Sazzy said:
You are correct...I have honestly just begun actual landing training. This instructor is very different from my first instructor. Both are very good, but my first instructor had me focus mainly on in-air maneuvers and then would land the plane himself most of the time, whereas my current instructor wants me to get more comfortable getting the plane off of and back down onto the ground.

That's why I love forums like these! Thanks, all, for your tips and advice.
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You first instructor sounds like a wiener. I had students landing on first lesson and frankly pretty much every instructor I know did the same. Good luck. Aviation is quite the journey.
 
FastEddieB said:
Some pilots like to trim during the landing flare. Nothing wrong with that if it works for them, and in a nose-heavy aircraft it may help.

But the landing flare is the one phase of flight where I do NOT want to trim out control pressure - it’s the gradually increasing need for back pressure that helps me feel what’s going on with lift and energy, and helps me achieve a slow, mains first touchdown at or near stall speed. For me personally, trimming that pressure out would make landing harder, not easier. But to each their own.
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Some Mooney guys like trimming heavily into the flare, but it's pretty unnecessary and kind of a risk on some if you go around.

Tarheelpilot said:
You first instructor sounds like a wiener. I had students landing on first lesson and frankly pretty much every instructor I know did the same. Good luck. Aviation is quite the journey.
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Yeah, my instructor had me land the plane on the first flight. In fact, it was probably my best landing in my first 10 hours.
 
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