Electric Trim on Landing -Acclaim

[daveydog]

Hello All,

I had an interesting event yesterday and I would really like some feedback.  

When I land my Acclaim, once I have the field made and on short final, I immediately use electric trim to trim up for the landing (as instructed when I got my check out training).  Yesterday, I did a go around, and when I added throttle, my trim was all the way up and I literally had to use both hands to push the nose forward to maintain a safe attitude... very scary.  I could not get the electric trim down fast enough and used manual trim to get it back into Take-Off trim range.  The weight on the stick was unreal... I doubt a lady would have been able to get it forward, it was that hard.  

 

Here is my question... is it a good idea to trim up on short final?  I think I now know the answer and I say NO, not after this event.  I feel the trim should be left alone and even though the stick may be a little heavier for landing, well worth it in the event a go around needs executed.  Trimming back down quickly is  not alway feasible on a short runway.  

 

The electric trim issue yesterday was very concerning and I would like feedback form other Acclaim or similar drivers as it relates to how you might use trim on short final.  What procedures do others use?  After going full flaps, I trim for glide slope, then once the field is made, I trim further for landing.  I guess the real question is, should I avoid the trim on short final and just leave it at glide slope trim?  Much appreciated.  

[Marauder]

Hello All,

I had an interesting event yesterday and I would really like some feedback.  

When I land my Acclaim, once I have the field made and on short final, I immediately use electric trim to trim up for the landing (as instructed when I got my check out training).  Yesterday, I did a go around, and when I added throttle, my trim was all the way up and I literally had to use both hands to push the nose forward to maintain a safe attitude... very scary.  I could not get the electric trim down fast enough and used manual trim to get it back into Take-Off trim range.  The weight on the stick was unreal... I doubt a lady would have been able to get it forward, it was that hard.  

 

Here is my question... is it a good idea to trim up on short final?  I think I now know the answer and I say NO, not after this event.  I feel the trim should be left alone and even though the stick may be a little heavier for landing, well worth it in the event a go around needs executed.  Trimming back down quickly is  not alway feasible on a short runway.  

 

The electric trim issue yesterday was very concerning and I would like feedback form other Acclaim or similar drivers as it relates to how you might use trim on short final.  What procedures do others use?  After going full flaps, I trim for glide slope, then once the field is made, I trim further for landing.  I guess the real question is, should I avoid the trim on short final and just leave it at glide slope trim?  Much appreciated.  

Not an Acclaim driver, but a long time Mooney owner. Are you going back to takeoff position on the go around? I trim for hands off short finals with full flaps. If I need to do a go around I am pulling the flaps back to takeoff position and using the electric trim to relieve the pressure. Would be interested to hear others on this. Your HP difference and heavier nose may make your go around a bit different than mine.

Also are your certain your electric trim is moving as fast as it should? Mine blows away my hand rotation of the trim wheel.

[N201MKTurbo]

When you do a go around in a Mooney (or touch and go) I bring the power up to about 15 inches to arrest the decent, then start adding down trim to take pressure off the yoke, raise the gear and then go to climb power. You can do all this in about 5 seconds. Don't be in a hurry...

[duke]

I fly an F and a m20s (310hp) and trim them both for proper approach speed and leave it there. Even with the F if you slam in full throttle on a go around you will get a very pronounced pitch up. Trick is to add enough throttle to arrest descent and establish a positive rate of climb while trimming nose down. Wen trimmed add power, trim, clean her up and go around and try again. With the planes we trained in 150 hp or so full throttle on go around didn,t produce near as dramatic affect. The more hp out front the more it will pitch nose up. Go out to someplace (training area?) and practice the technique at a safe altitude and you will soon learn how much throttle to use.

[PMcClure]

I wonder if you changed your flap settings? In my ovation2; if I remove flaps on the go around before trimming down it it very difficult and scary to hold the nose down in a normal attitude.

[carusoam]

Clearly the same effect from 180hp M20C to 310hp long body.

It is important to know how you will handle this situation in your area of the world.

Especially in or near IFC.

Basic training in a C152 trains full throttle on the go around decision. Flaps are full down and climb is anemic with 108hp on tap, near MGW.

It's definitely good to review these important details with your CFI.

That's my experience, YMMV.

There is a discussion way back on MS of someone losing an F or J in New England, she was a flight instructor performing a go around. I'll see if I can find the reference...

Best regards,

-a-

[John Pleisse]

A go around would require a lot of forward pressure. I would humby submit you make sure you don't land the plane with the trim. This could be an extension of flying the plane with trim all the time. Duke's approach to leaving the trim set is correct IMHO. In my J model, a go around requires very significant forward pressure. Likewise, landing flare should not be effortless and require a few pounds of back pressure. If you trim "up" too much for your flare, you are set up for a dicier go around.

 

All that aside, there was an emergency AD a year or two ago for runaway trim/stuck stabilzer issues on certain serial number Acclaims. This originated in Poland. Is your SN a hit? If so, I am sure it was checked, but surely it wouldn't obsolve furhter vigilance. 

[RJBrown]

Unless more flaps are called for I land with flaps in take off position. If a go around is needed getting to take off position from full is a head down operation at the most critical time. I also useually land on a 10,002' runway. Flaps and trim are in position for a go around on every landing. Eliminates all reconfiguration drama if a go around is called for. Later planes, mine is a 1990, have a 4 position switch that allows a click up for take off position without watching. A simple thing but a big saftey up grade. 

[duke]

I am sure that is what happened to my eagle while it was registered in the USA. Farmington NM in about 03. Was being flown on a ferry flight by an airline pilot.Attempted a go around and lost it.

[Hank]

I also normally land with Takeoff flaps, trimmed for hands-off descent, unless I need more flaps to get down. For go-rounds, full power does require stiff-arming the yoke while spinning the trim, even with my anemic 180-hp; I can only imagine the beast you unleashed.

 

I've read about people using moderate throttle [more than enough to stop the descent] while they clean up and retrim, then advance the rest of the way. Finding that approximate spot is what Instructors and the Practice Area are for. Check Don Kaye's website, see if he has any advice listed there.

[duke]

I was taught that tecnique buy my instructor when i bought the F. Think about what would happen if the seat back broke at the moment of lots of forward pressur to hold nose down. Ther is a post here on broken seat back bracket a while ago.

[harrispa]

My experience is similar on my long body M20S.  I do trim for landing.  On go around, There is a lot of pressure initially.  At the slow speed, the trim doesn't feel as effective (fast) as at higher speeds.  I hold the forward pressure with immediate electric trim, Positive rate, flaps to takeoff position (now the plane is just like takeoff, gear is down and flaps at takeoff), gear up, then rest of flaps. As always YMMV.   Other High performance planes I have experience with (Twin Comanche, Bonanza) have similar traits, but I don't recall quite as much pressure as in the Mooney.

[carqwik]

Here's my 2 cents...first, very little trim adjustment should be needed beyond short final.  Get the speed right on target at the last 50' or so and you won't need to continue trimming in the flare so much.  (Of course, the long body M20s are very trim-hungry airplanes so its important to actively use it to reduce stick forces.)  But on a go around with full flaps and low speed, what you encountered is exactly what should have happened using your likely procedure....the best bet is to advance the throttle just enough to arrest the descent (about 25" in my Bravo) and start a slow climb...while adding power, it's right rudder as well..and start trimming nose down...then take the full flaps back to T/O flaps...wait...make sure you're climbing a bit...then gear up.....then a bit more power (30")....then follow your normal takeoff procedure from there as you add power and take out the rest of the flaps and add rudder trim.

 

The key is not to go to full power immediately....it's not needed...and start trimming away the nose up bias immediately (and add right rudder)...then start cleaning up slowly while adding more power as stick forces reduce.  Try it and you'll see it doesn't take a ton of power to arrest the descent in a long body Mooney....and less power means less stick force needed.

[PMcClure]

In the r model, the pitch up effects of removing flaps is more dramatic than in my f model. I am pretty sure the Ovation POH says to establish positive climb rate AND correct trim before removing flaps. In IFR this could be a very serious issue. As for after landing, I don't touch a thing until after calling clear of runway.

[Cris]

My experience is similar on my long body M20S.  I do trim for landing.  On go around, There is a lot of pressure initially.  At the slow speed, the trim doesn't feel as effective (fast) as at higher speeds.  I hold the forward pressure with immediate electric trim, Positive rate, flaps to takeoff position (now the plane is just like takeoff, gear is down and flaps at takeoff), gear up, then rest of flaps. As always YMMV.   Other High performance planes I have experience with (Twin Comanche, Bonanza) have similar traits, but I don't recall quite as much pressure as in the Mooney.

If you are are using power for altitude and pitch for approach airspeed as you should then you will have up trim close to max at touchdown. This is a good thing as you will not have a prop strike as you reduce power to idle at about 3' above the runway and your airspeed will rapidly decay. The A/C is almost at the flare and requires very little back pressure to land correctly In the Ovation/Eagle and similar long bodies. Your approach airspeed will be 75 kts less 5 kts at 300 lbs under gross and full flaps. On the go you will have significant upforce which can be easily overcome if you are not surprised by the effort. Just try two hands on the yoke while triming down and you find it is no big deal. The only differance I might have with the above post is to leave the gear down until above any obstacles. One last point is that if you do not practice this there will come a time that you really need to do it for real as in landing long and that will be the time that one is "really surprised" . You can practice at altitude before commiting to a real landing.  

[daveydog]

You all are excellent.  This was extremely helpful and valuable.  I'm headed out again to practice now.  I will report back.  I know where I went wrong, and Duke's comment about the seat back is particularly scary.  I like the idea of adding only enough lower to arrest the decent while trimming.  It seems to me, any excess load and stick pressure is unnecessary.  Why load the airplane, the seat, or the mind with extra workload.  I also read the POH again and I agree with PMcClure.  What I am going to do is:

1.  Add slight power to arrest decent

2.  Establish a positive rate

3.  Trim for T/O

4.  Flaps to T/O

5.  Add additional power 

6.  Wheels up after clear of obstacles

 

This seems most prudent and practice important so its automatic.  

 

Thank you again.  This was excellent feedback!

[daveydog]

Okay... it was an interesting discovery.  The advise given was spot on.  Thank you once again.  

[jetdriven]

A go-around is usually needed because of something happening (botched landing, traffic conflict, windshear, etc), and adding partial power, trimming, and then changing configuration before going to rated takeoff power is a whole lot of steps (and time) when close to the ground. The objective is to get away from the ground before anything bad happens.  All those steps seem to be a cover up for the improper technique for trimming in the flare. Trim it to your final speed, perhaps a bit more trim as you reduce power, and flare the plane.

 

I have not flown a long-body, but in the M20J, trimming for 65 knots is about 3/4 up, and firewalling it does not produce any unusual stick forces to maintain normal flight.  Another cool feature is the flap and trim motors run at the same speed and cancel each other out. Move the flaps, move the trim for the same period and the pitch forces are neutral.

 

You guys saying a long-body does not do this?

[Cris]

Byron- Long body works the same but you do not need much of a flare as the A/C is already in the correct attitude for landing. I think the original OP was not actually landing the A/C but performing a go around before touchdown. I'd suggest he actually land as the tecnique will be more clear. And yes your are pointing out an issue with all of the extra steps. KISS- full power while triming down, positive rate, flaps takeoff or flaps up, gear up after obstacle clearance. Some will use two hands on the yoke for a bit more comfort.     

[daveydog]

Byron, I agree with what you are saying.  Thats is what I did which caused the problem (severe nose up stick with one exception... I trimmed back for a light stick.  I don't do that anymore.  

 

I have since done many approaches and now simply trim for glideslope/speed and leave it alone.  That puts me in the white arc or very close. If I go around  (in my case it was windshear), I add generous and consistent power while also trimming and going to T/O flaps.    Its all seamless.  Power, trim, flaps.  Positive rate I put the wheels up. The lesson here is NOT to trim back outside of T/O range on final.  This was the problem.