Making sense of NTSB report for M20F N9339M

[midlifeflyer]

20 minutes ago, Shadrach said:

In my view, the genesis of the discussion was born out of the recommendation in an Mooney Owners Manual that certain pattern speeds be used without any consideration given to weight.  The real-world operating weight of my aircraft can vary by more than 800lbs.  That represents an 11mph difference in stall speed.  Approach speeds are up stream of stall speed.

I don’t disagree at all. But what I’ve been reading suggests some are seeing a requirement to use full flaps for landing just because the published data is based on it. 

[Shadrach]

2 hours ago, Hank said:

But the handful of landings I made in an F were better when I used Full Flaps, the midbody handles surprisingly different from my short body at low airspeeds.

I agree completely. This came as huge surprise to me. Flying both aircraft on the same day cemented it.

[00-Negative]

1 hour ago, Shadrach said:

I have flown both it and my F model in the same day and I can grease the F model on smoothly, but the sea seems to have an extreme deck angle before the wing pays off and it plunks on with a thud. 

This. My short body E with passengers and baggage in the rear ends up with an uncomfortable deck angle before it's ready to land with full flaps. Half flaps yield much better results when I have weight in the back seats and baggage. Also I think much better on the airframe and landing gear to touchdown lightly 5mph faster than to plunk down at a slower speed. The landing characteristics of my plane vary widely depending on wind and weight distribution. 

-David

[Hank]

1 hour ago, Shadrach said:

It’s not a limitation. As you know, the only limitations in the AFM/POH/OM are in the limitations section.  

In my view, the genesis of the discussion was born out of the recommendation in an Mooney Owners Manual that certain pattern speeds be used without any consideration given to weight.  The real-world operating weight of my aircraft can vary by more than 800lbs.  That represents an 11mph difference the sea seems to have an extreme deck angle before the wing pays off and it plunks on with a thud. I’m going to try some different landing configurations to see if I can prove my touchdowns.

Welcome to the Partial Flap Club!! Read the Manual, see what it says; mine has both paragraph discussion abs checklists.

I have Flaps--to Takeoff at pattern entry, and leave them there until I'm on final, and as quoted from my Manual above, set them as needed.

Here's a wordy description:

Have fun with the C!

[Yetti]

The data for landing over a 50 foot tree is great if you know the distance of the tree from the runway.

dropping with a thud means you are running out of energy before touch down.   Not a good management of energy.

One trick with the long body is to carry a thing of water bottles in the baggage area.    You can take it out if carrying passengers, but it did help with the landings to get some weight back there.   Also you are removing the PIO tendency and it helps to keep the nose up if you release too much yoke.     

The other thing is to grab 2 handfuls of trim right at the fence/threshold.     This lightens the nose and helps keep it up

My theory on full flaps is there is 4 inches of full flaps and the runway.   So full flaps adds to the float if you are fast.   With the long body the weight is overcoming the float.

Some more data from the S manual.

of course it is missing the up slope or down slope of the runway.     Yesterday wind from the north 3% up slope. 

[Shadrach]

On 12/3/2025 at 10:36 AM, Yetti said:

The data for landing over a 50 foot tree is great if you know the distance of the tree from the runway.

dropping with a thud means you are running out of energy before touch down.   Not a good management of energy.

One trick with the long body is to carry a thing of water bottles in the baggage area.    You can take it out if carrying passengers, but it did help with the landings to get some weight back there.   Also you are removing the PIO tendency and it helps to keep the nose up if you release too much yoke.     

The other thing is to grab 2 handfuls of trim right at the fence/threshold.     This lightens the nose and helps keep it up

My theory on full flaps is there is 4 inches of full flaps and the runway.   So full flaps adds to the float if you are fast.   With the long body the weight is overcoming the float.

Some more data from the S manual.

of course it is missing the up slope or down slope of the runway.     Yesterday wind from the north 3% up slope. 

I have been landing Mooneys for about 27 years (almost half my life) and have logged 100s of landings into <1600' strips.  I am long term member of the church of energy management. Do you have any short-body time?  The short body feels very different from a mid-body in the flare to touchdown. I suspect it has to do with the shorter arm (and moment) from the empennage to the center of lift.

[Yetti]

1 hour ago, Shadrach said:

I have been landing Mooneys for about 27 years (almost half my life) and have logged 100s of landings into <1600' strips.  I am long term member of the church of energy management. Do you have any short-body time?  The short body feels very different from a mid-body in the flare to touchdown. I suspect it has to do with the shorter arm (and moment) from the empennage to the center of lift.

I would suggest the relation of the wing profile to weight is more the factor.

The ability to thud a Long body onto the runway is much greater than the F model.   In the long body if you pull out too much energy by reducing the throttle while bleeding off energy, there can develop a vertical sink that I never had in the F.    I experienced this with the instructor.   There I was on approach, letting energy bleed off, with too little throttle.   At .12 miles to threshold the vertical sink rate increased.   I caught it with throttle, but left the throttle in for too long. (it really was just a blip of throttle)(the Instructor felt it also and confirmed the throttle to catch the sink) Now the energy is way too much for touch down at an acceptable spot on the runway.   I could have popped the speed brakes.   I just chose the go around.     Which the instructor also confirmed and suggested he could have salvaged the landing, but it is a 6000' strip.    I am wanting to always be within 4000'.

Tuesday was a pretty day to fly. No wind.     with Medium braking I was making the 2000' turn off.   But I was coming in with 3 red dropping into the 4 VASI 

The chart above says 2200 feet with maximum braking. 

[Yetti]

And why do I say Laminar flow wing profile is the reason.    Because a little trick I was shown.   On take off if you dip the nose to level after lift off for just a second or two the plane will speed up and get the wing flying better.  Now you can go up faster than if you just lifted off with a constant angle.   So it would make sense there is a speed relative to weight that the laminar flow is not doing as well in the lift category as the plane slows down.  

[MikeOH]

3 hours ago, Shadrach said:

I have been landing Mooneys for about 27 years (almost half my life) and have logged 100s of landings into <1600' strips.  I am long term member of the church of energy management.

BINGO!

At my home drome (KPOC) I have never missed turning off at taxiway D, 1600 feet from the threshold.  That's calm wind.  If I have 10 kts on the nose I can make taxiway C with heavy braking, 650 feet from threshold.  Minimum energy at touchdown!

[Hank]

1 hour ago, MikeOH said:

BINGO!

At my home drome (KPOC) I have never missed turning off at taxiway D, 1600 feet from the threshold.  That's calm wind.  If I have 10 kts on the nose I can make taxiway C with heavy braking, 650 feet from threshold.  Minimum energy at touchdown!

I usually make the midfield turnoff at home (5400'; the turnoff is significantly off-center towards 18, which is downhill). But I never brake hard unless necessary,  and when landing uphill on 36 I don't brake at all.

Whether I make the turnoff on 18 is generally determined by whether I'm high or fast, which makes me land long, but because there's more room on 36 (plus being uphill), it's almost never an issue that way.

I rarely use full flaps, but tend to use more as windspeed decreases to get the descent angle I'm used to.