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The Mooney Pull & Take Off Trim ???


DCarlton

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I never could understand a good rationale for putting the flaps down in increments. In a normal pattern, I put the gear down midfield downwind because I want some time to ensure that it is down before doing anything else, and then I reduce power to the top of the yellow arc on the tach on my M20J, hold altitude and put down full flaps and trim for 70-75 KIAS and begin a descent. As the airplane slows, the RPM usually falls to the bottom of the yellow arc. If I have the G3X altitude bug set to pattern altitude, I usually get the 200' alert about the time I turn base and I get the "Five Hundred" callout shortly after turning base. I use that as a "check gear" indication. On final, I adjust speed slightly to final approach speed based on weight and wind gustiness and use whatever power is needed to maintain the PAPI glidepath (if one is available).

My final speed wanders a bit unless I really work at it. When trimmed for 65 KIAS (1.3 Vso at 2300 lb) my airplane has a trim speed band of 63-68 KIAS so the workload is high to maintain exactly 65 KIAS and I don't bother until very short final. 

Skip

Trim speed band info, for those interested.

Even though I replaced the eyeballs where the yoke shafts penetrate the instrument panel, there is still some friction in the controls which causes the airplane to be equally happy maintaining any speed within  a band around the trim speed. To test this I used a method suggested by Ed Kolano. I climbed to 4500', and configured the airplane for approach and carefully trimmed for 65 KIAS. Then I slowly raised the nose to get 55 knots and let it slowly come back down (slow is important to avoid exciting the phugoid -- you don't want the airspeed to overshoot for this test) until the airspeed stopped changing. I noted that it held 63 KIAS. Next, I lowered the nose to get 75 KIAS and let it slowly come back up until the airspeed stopped changing and it held 68 KIAS. I repeated this three times with results within half a knot. 

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Had a short local flight today, enjoying the cool clear air. Remembered to take pictures of trim before takeoff and after landing.

I pull to takeoff at 70 mph, trim at the top of the takeoff mark when solo or two people, no bags; had about 3/4 fuel today.

20221120_135726.jpg.b3059b033612cbff5ff040e3f8fa3213.jpg

Pattern speed is 90 mph with Takeoff Flaps, slowing to 85 mph on final and 70-75 on short final depending on weight. This was my landing configuration today--one TnG; one full stop, taxi back; then full stop and back to the hangar.

20221120_145732.jpg.755062e08094d4aaae8a8bc4f5098ba2.jpg

Today I paid attention, downwind was about 14-15" with Takeoff flaps; dropped gear to begin descent and reduced power to 12-13", which put me on glideslope. One landing I ended up at 11" and had to add power to reach the runway.

Winds were 320@6 to 360@8, using Runway 36; both runway exits required adding significant throttle to reach the 2500' exit, but it was uphill--landing downhill on 18 I can be long and coast to the 4500' exit after it levels off.

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6 hours ago, PT20J said:

I never could understand a good rationale for putting the flaps down in increments. In a normal pattern, I put the gear down midfield downwind because I want some time to ensure that it is down before doing anything else, and then I reduce power to the top of the yellow arc on the tach on my M20J, hold altitude and put down full flaps and trim for 70-75 KIAS and begin a descent. As the airplane slows, the RPM usually falls to the bottom of the yellow arc. If I have the G3X altitude bug set to pattern altitude, I usually get the 200' alert about the time I turn base and I get the "Five Hundred" callout shortly after turning base. I use that as a "check gear" indication. On final, I adjust speed slightly to final approach speed based on weight and wind gustiness and use whatever power is needed to maintain the PAPI glidepath (if one is available).

My final speed wanders a bit unless I really work at it. When trimmed for 65 KIAS (1.3 Vso at 2300 lb) my airplane has a trim speed band of 63-68 KIAS so the workload is high to maintain exactly 65 KIAS and I don't bother until very short final. 

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I think there are a bunch of reasons. The most simple is that most of us learned to deploy flaps in increments while flying trainers.

Practical reasons?

  • many vintage birds have a low Vfe. (>100MIAS for me).  I simply don’t wish to fly that slow until needed.
     
  • I think it’s easier on the equipment to deploy in steps as speed bleeds off rather than to dump everything out at the top of the white arc. Many of our planes are subject to an SB due to possible stub spar cracks at the actuator.
  • While Mooney flaps are not especially draggy compared to other planes, full flaps are pretty draggy relative to the clean airframe. I don’t need or want the drag of full flaps until final so no point in making extra noise dragging my way there by hanging them out early.
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We've gone from the Mooney pull and take off trim to landing with full flaps... but...  because of all the "encouragement" on MS (full flap shaming), I went out today on a calm day without much traffic in the pattern and tried several landings using full flaps and slower final approach speeds.  I trimmed for 80 mph after turning final and kept it at 80 across the fence.  Didn't check the speeds after I crossed the threshold; just waited for the landing.  I must admit they were the most serene four landings I've experienced in a long time.  Downright relaxing.  :> Winds were only about 5 mph and I was light with about 20-25 gals of fuel.  Biggest problem now is I have to add power and taxi to the turn off.  During all the celebration, I broke the little latch on my pilots side vent window.  Gotta source one of those...  suggestions welcome.  

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I visited a private strip today. It's 3500' long and paved, but it is very bumpy with a hump in the middle. 

So did I use the "Mooney pull" on takeoff? No. If I had done that the first bump or two would have surely launched me into the air prematurely.

Did I hold the nose down for a higher takeoff speed? No. If I did that I would risk the airplane skittering around the runway on the verge of LOC (did I mention this strip is also narrow?).

What I did was use the rough water seaplane takeoff technique and "flew" the elevators to maintain a constant pitch attitude as nearly as possible as it accelerated to the point where it could lift off. The airplane was fully under control during the entire takeoff run, and though it was bumpy, it did not leave the ground until ready to fly.

I think the point of this whole thread is that no one technique works in all situations. Sometimes more flap is better; sometimes less. Sometimes the Mooney pull is appropriate, sometimes not.

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2 minutes ago, PT20J said:

I visited a private strip today. It's 3500' long and paved, but it is very bumpy with a hump in the middle. 

So did I use the "Mooney pull" on takeoff? No. If I had done that the first bump or two would have surely launched me into the air prematurely.

Did I hold the nose down for a higher takeoff speed? No. If I did that I would risk the airplane skittering around the runway on the verge of LOC (did I mention this strip is also narrow?).

What I did was use the rough water seaplane takeoff technique and "flew" the elevators to maintain a constant pitch attitude as nearly as possible as it accelerated to the point where it could lift off. The airplane was fully under control during the entire takeoff run, and though it was bumpy, it did not leave the ground until ready to fly.

I think the point of this whole thread is that no one technique works in all situations. Sometimes more flap is better; sometimes less. Sometimes the Mooney pull is appropriate, sometimes not.

Skip

Actually, I think the constant pitch method probably does work in all situations.

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On landing I don’t do partial flaps either, probably would if Mooney had put nice notches like Cessna did. I do use TO setting for TO.

My technique is to slow to the top of the white arc, then drop gear (I’m convinced the gear see lower loads at lower speeds, did I mention I’m paranoid about the gear?), that slows the aircraft to well in the arc and I drop full flaps, then I usually fly at 2000 RPM or higher as necessary until I have a sight picture for landing, then reduce to idle and land, this is because of the yellow arc between 1500 and 2000. To get to the white arc I often descend 100’ or so lower than pattern altitude, then climb at idle, she slows down quickly doing that.

The rough water takeoff method is very similar to a soft field technique for those without seaplane ratings, if you don’t go to Jack Brown’s at BFR time and fly the Cubs, they may still have a Maule for those that are challenged by gravity, it’s a hoot.

All of these techniques are what I call Graduate level flying, initially we are taught methods and procedures that are easy, difficult to mess up and they are therefore safe for fledgling pilots, but over the years and a few thousand hours flying several different airframes, you may learn new techniques. For instance nothing teaches you how to fly severely overloaded under powered aircraft better than Ag flying does, that’s techniques and knowledge that sometimes is useful in mountain flying regular GA airplanes, where our N/A airplanes become overloaded and severely underpowered.

Practicing many autorotations in a helicopter makes you good at spot landing airplanes at idle, you learn where to place the intended point of landing on the windshield before pulling power until it becomes habit.

Most everything crosses over.

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55 minutes ago, PT20J said:

I visited a private strip today. It's 3500' long and paved, but it is very bumpy with a hump in the middle. 

So did I use the "Mooney pull" on takeoff? No. If I had done that the first bump or two would have surely launched me into the air prematurely.

Did I hold the nose down for a higher takeoff speed? No. If I did that I would risk the airplane skittering around the runway on the verge of LOC (did I mention this strip is also narrow?).

What I did was use the rough water seaplane takeoff technique and "flew" the elevators to maintain a constant pitch attitude as nearly as possible as it accelerated to the point where it could lift off. The airplane was fully under control during the entire takeoff run, and though it was bumpy, it did not leave the ground until ready to fly.

I think the point of this whole thread is that no one technique works in all situations. Sometimes more flap is better; sometimes less. Sometimes the Mooney pull is appropriate, sometimes not.

Skip

I tried a different trim setting today for take off too and pulled sooner that usual (around 70 mph).  Nothing to write home about but I did notice some drift (we had a light crosswind); I'm not compensating for crosswinds well enough when I leave the ground at a lower speed.  I need to work on that technique as well.  

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On 11/21/2022 at 6:08 PM, DCarlton said:

 I must admit they were the most serene four landings I've experienced in a long time.

low-energy landings are the best landings! 

I think the fast landings in Mooneys is a result of overcompensating for the unforgiving stall characteristics of these planes. 

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I fly a 231. My elevator hangs down. I flew a J before the K and noticed the two were different, the J elevator was level when the aircraft was parked. When I first started flying my aircraft I set trim at the takeoff mark but that required a strong pull to rotate. I flew with an experienced Mooney instructor at a Mooney PPP who also owned an K and he taught me to adjust the trim above the takeoff line. That pretty much is where it is after I land, so there is not much adjustment between landing and takeoff. My aircraft has a forward CG, sometimes I will fly alone on one trip and then cram two full size guys in the front seat the next trip, it is a good idea to trim up a little more for takeoff but if I don’t do that it is not a very big deal. Very shortly after takeoff you are going to go through some trim adjustments anyway when the gear and then the flaps come up. I am half flaps for most landings. Yes, full flap landings are serene in low steady wind conditions, but we don’t get that here very often and my experience with it is that practicing that kind of landing too much gets addicting, you set yourself up for failure the next time the wind is high, gusty, and 60 degrees from the runway, which is quite a bit of the time where I fly. 20 kts of wind is just another day in the Dakotas.

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Another reason to lower flaps in increments is i manually adjust trim instead of wearing out my electric trim motor. The autopilot uses the motor enough as it is. It’s much easier to trim with small flap changes than to trim starting with full flaps. This also allows me to feel how well the trim screw is lubricated as it is easier to change trim after an annual. 

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  • 1 month later...
On 11/19/2022 at 11:33 AM, DCarlton said:

For the full flappers out there, where in the pattern do you drop full flaps (the final notch)?  Are you operating out of a busy airport with a full pattern and jets on the straight in?  If so, how do you deal with a tower that often wants you to keep your speed up?  Thanks.

Half on base leg, and full on final. Just how I do it. Not right or wrong.

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On 11/23/2022 at 9:19 AM, rbp said:

I think the fast landings in Mooneys is a result of overcompensating for the unforgiving stall characteristics of these planes. 

this 100%

and you would think that this overcompensating mindset would convince pilots to land w  full flaps, but there are different (and contradictory) myths about full flap landings 

 

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On 11/23/2022 at 6:19 AM, rbp said:

low-energy landings are the best landings! 

I think the fast landings in Mooneys is a result of overcompensating for the unforgiving stall characteristics of these planes. 

First off I totally agree that slowest landings are by far the best landings.

But I don't understand the suggestion of "unforgiving stall characteristics" unless perhaps you are referring to an unfounded fear some pilots have about stalling period and feel they must add more speed!

Having stalled what must be over a 100 Mooney's from short bodies to Acclaim Ultras this fear is pure myth. The only time I've seen any issue is in the very rare Mooney that had previous wing repair from an accident and  drops a wing faster than normal. But more often excessive wing drops are from the pilot trying to use aileron to hold up the stalling wing - a big no-no! 

If a pilot has a deep rooted fear of Mooney stalls, installation of Vortex Generators should really help them get over it. The Mooney wing just mushes with vortex generators. Its quite amazing.  

Personally the Only time I don't land with full flaps is if I am doing a simulated emergency power off landing and need to keep the flaps up to make the runway or I am practicing a flapless landing. Or if I landing IFR at minimum visibility w/o flaps in which case I won't alter configuration at minimums for landing. But normally I am doing an approach at 100-110 kts and will use full flaps to get help get slowed down and trimmed to Vref for landing.  

 

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9 minutes ago, McMooney said:

One thing i've noticed about my birdy, starting to think i need rigging, she's usually trimmed full nose down or pretty close when straight and level with a passenger and bags.  Anyone else?

 

First check your trim indicator,  when you go from full nose up to full nose down is the trim indicator going to near both edge limits? 

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16 hours ago, McMooney said:

One thing i've noticed about my birdy, starting to think i need rigging, she's usually trimmed full nose down or pretty close when straight and level with a passenger and bags.  Anyone else?

Mine is similar.   I can run out of down trim during a fast descent, but not by much.   I've not attempted to rerig it because the indicator seems fine when set for takeoff, and after landing it's usually back in the same spot, which seems to be normal for most people (with a mid-body, anyway).    I suspect it isn't quite exactly right, but it's not causing me any issues other than minor annoyance running out of down trim once in a while.

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On 1/24/2023 at 5:43 PM, rbp said:

Mooney’s have a mythical reputation for very poor stall characteristics 

How many other planes can stall on base to final… and recover before hitting the ground?

I’m more of a fan of having the flaps down before the turn to base… and nicely trimmed…

Sure the drag is higher…

And the stall speed is lower…

But the only person that has had the engine die on final… had so little fuel, it ran away from the pick-up as the nose pointed towards the ground…

Use caution with maintenance flights and very little fuel in the tanks… they can lead to a small surprise….  :)
 

I’m also a fan of low bank angle turns…  I giant U-turn is OK with me…  (there is a name for this technique around here somewhere) George gave a presentation on it a few years back…

PP thoughts only, not a CFI…

Best regards,

-a-

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