M20J / K on grass

[IndyTim]

As I've been looking at J (and K) Mooneys, it's noteworthy how many have had engine teardowns because of prop strikes.

I understand the requirement for well-controlled approach speeds, and that landing too fast is one of the primary causes of prop strikes due to the float/hop dynamics. And that this is both a function of the M20 aerodynamics, as well as its relatively short stature on the ground.

Does this mean that landings on grass strips are too risky for an M20? Or are there some pilots who are able to use the right techniques, and who can consistently land on grass without endangering the prop?

And is there anything that can be done to improve effectiveness/reduce risk on grass or soft fields? Going to a 3-blade, smaller diameter prop would help, no?

Does the gear height compress with aged biscuits? Is this also a factor?

I'm looking hard at M20's, but also considering a Debonair. In this category, methinks the Deb is the winner, and landing on grass strips out west is something that I'll want to do, occasionally. It's not a showstopper capability, but definitely up there on the list of nice-to-haves.

[Jeff_S]

A lot has been written on this board over the last year so you should search out these topics. The general consensus is that any of the short body Mooneys (pre-J or -K) are perfectly fine on grass. The mid-body J is generally fine, although you may want to have the inner gear doors removed if you're going to land on any rougher or high-grass strips. The -K may start to be problematic because of the heavier nose, and any of the long-body Mooneys most people do not like to land on grass strips again because of the heavier nose and general weight characteristics.

That said, I'm sure plenty of people will land anything on turf as long as they know the strip and are comfortable with their airplane. Search for videos by piperpainter on this forum to see some extreme examples!

As to wear on the shock disks, if the field is not overly rough I don't think that's a big problem. Turf fields are softer than pavement and I think they put less strain on the shocks all else being equal...assuming you're not on a washboard or something.

[Oscar Avalle]

Dear Tim

Mooney are great airplanes to fly and to land, as long as you use the right procedures. I had the same concern regarding softfield landings, but again, as long as you follow procedures and keep the speeds under control you will just enjoy landing the plane. Of course it has its limitations, Mooneys have not been built for bushflying...but a normal grass field with a good technic... no problem. There is a full discussion about softfield landings in this forum.

[The-sky-captain]

Tim,

Check out piper painters gallery to see how Mooneys (C model) handle non paved strips. Me thinks the pilots ability is just as important to landing on grass as the plane is...

[jlunseth]

I have a 231 K and have done a number of grass landings and takeoffs. With proper technique, landings are a nonissue. You will find that grass strips, being airfields, are generally well maintained. You might have issues the morning after a thunderstorm, but other than that the mysterious gopher hole that dings the prop really does not exist.

The takeoffs in the K were another matter. Takeoff technique is to hold full back yoke to protect the nose wheel, then the plane raises into ground effect and you stay there until you have sufficient speed to climb. However the nose of the K is quite heavy. I found that the plane did not move very elegantly into ground effect, and flew at quite a nose high attitude for too long when very near the ground. This is manageable with rudder, but not a good situation so I have stopped doing grass fields unless necessary.

[IndyTim]

Dear Tim

Mooney are great airplanes to fly and to land, as long as you use the right procedures. I had the same concern regarding softfield landings, but again, as long as you follow procedures and keep the speeds under control you will just enjoy landing the plane. Of course it has its limitations, Mooneys have not been built for bushflying...but a normal grass field with a good technic... no problem. There is a full discussion about softfield landings in this forum.

I think I found the thread, thanks. I just discovered the "search by phrase" feature!

[Hank]

Tim--

Several Mooney-specific points:

• Grass fields are generally OK. Inner gear doors are problematic for frequent grass landings. Nose-heavy models are also problematic.
  
• 3-blade propellers [except for one of the new composite models] are the same diameter as the 2-blade. No extra ground clearance.
  
• Shock discs do compress a minimal amount. If stack height is reduced by a minor amount [~½" IIRC], they should be replaced. Worn discs will not have an effect on ground clearance unless on the nose wheel.
  

Have fun flying! I know some people whose Mooneys are based on grass strips, and I visit grass strips occasionally.

Do check out Piperpainter's videos . . . . .

[jetdriven]

I have landed my J on grass a few times and once got stuck in the mud next to an airport ramp when being parked on grass. The only things to worry about on the doors is mud building up inside them when it gets 4" deep, and that ends up in your gear well right along with your spar when the gear comes up. Clean it thoroughly after operating near mud. Another thing is rough strips. The Mooney does not have much ground clearance for the prop. We had a nose tire go flat on landing and there is only 3" or so clearance with a flat tire. If taxiing over rough grass go very slowly, slower than a walk. I can see a situation where you hit a gopher hole, compress the nose shock discs, and could hit the prop on the ground because the airplane pitches a lot on rough ground while taxiing. Taking off or landing is no problem, as the elevator provides a lot of force to raise the nose and the nosewheel floats over the gopher holes.

Make real sure your gear down preload is rigged properly as well. If any of the 3 landing gear have insufficient down preload, rough ground could collapse the gear.

[IndyTim]

... so it looks like the very best M20 variant for my needs, which consist of 98% economy flatlands commuting and 2% flight into backcountry airstrips out west, would be a turbo-normalized J! Keep the weight down in the nose, get great fuel economy, yet still reach the higher elevation airports/air strips.

A rare beast, I'm sure. Anyone have a nice one for sale?

[aaronk25]

Protect the nose....protect the nose.....protect the nose......controls all the way back while taxing, taking off and as soon as possible with out becoming airborne after landing. Keep the nose up!

[Jeff_S]

... so it looks like the very best M20 variant for my needs, which consist of 98% economy flatlands commuting and 2% flight into backcountry airstrips out west, would be a turbo-normalized J! Keep the weight down in the nose, get great fuel economy, yet still reach the higher elevation airports/air strips.

A rare beast, I'm sure. Anyone have a nice one for sale?

There are a few out there, but you can make your own. Just buy the bird you want and budget another $40K or so to buy the STC from M20Turbo and have your A/P install it. Several of us have contemplated doing that very thing with our J's but I don't think anyone has taken the plunge lately.

[N201MKTurbo]

I have an M20Turbos J. I'm not sure if I would pay $40K for it. When I bought this plane, I paid an extra 20K for it. It was already installed in the plane. I had an M20F for 19 years before I bought this plane. I used to fly it all over the Rocky Mountains, including a few landings at Leadville, CO. I never had any trouble getting into high altitude airports with the NA M20F.

[laytonl]

I fly a J off grass at a private fly in community. The strip is 3,000 and well maintained and have never had any problems. I Leave the gear doors on. Lee

[RJBrown]

I was once directed into a gopher hole at an airshow in my Rocket. Cost my insurance 3 blades and a engine tear down. Last time I took that bird through the grass. Even at Oshkosh I ended up with green blades. I don't think the turbo issue is as much about take offs from Leadville as it is about climbing high. Having owned a Rocket I get uncomfortable when unable to climb with authority. There were times yesterday that I saw 65 knot ground speeds as I tried to maintain altitude over the mountains. When a mountain wave can push up and down at over 1000 fpm it is nice to be able to get above the wave.

[M016576]

I was once directed into a gopher hole at an airshow in my Rocket. Cost my insurance 3 blades and a engine tear down. Last time I took that bird through the grass. Even at Oshkosh I ended up with green blades. I don't think the turbo issue is as much about take offs from Leadville as it is about climbing high. Having owned a Rocket I get uncomfortable when unable to climb with authority. There were times yesterday that I saw 65 knot ground speeds as I tried to maintain altitude over the mountains. When a mountain wave can push up and down at over 1000 fpm it is nice to be able to get above the wave.

Mountain waves and rotors can extend well above FL350. Climbing into high strength jet streams can expose you to CAT. Either way, flying a single engine prop aircraft over mountains in high wind scenarios increases your risk profile. That said, I fly my J over the Rockies on a regular basis, and mitigate the increased risk by flexing my weather go-no go criteria. A jet can handily fly out of CAT and most mountain wave turbulence. A TC or NA single engine aircraft can fly out of some downdrafts, but when it comes to the big stuff- we all get hit equally. Check out some of the pictures of B-52's and 707's that hit mountain waves / CAT. Brutal stuff! I think the magic number is something like 25kts over a ridge and a decent visual indicator being lenticular clouds...

[carusoam]

Have you ever experienced the real empty feeling of losing altitude faster than you can climb?

I got that on an IFR training, night flight. Climbing at Vy, and losing a couple hundred fpm in hills over north Jersey, in a C172.

Losing altitude in a Rocket over the Rockies, supreme confidence, or wicked big empty feeling?

Best regards,

-a-

[M016576]

Have you ever experienced the real empty feeling of losing altitude faster than you can climb?

I got that on an IFR training, night flight. Climbing at Vy, and losing a couple hundred fpm in hills over north Jersey, in a C172.

Losing altitude in a Rocket over the Rockies, supreme confidence, or wicked big empty feeling?

Best regards,

-a-

+1. An area of extreme vulnerability in mountain flying is landing, as well. Wind shear induced by CAT or mountain waves can pull jets, twins and singles down at speeds over 6000 fpm. A big part of mountain flying is the decision making process leading up to and through the flight. High winds and turbulence don't discriminate between aircraft, and the difference between a rocket and an E model is pretty small once you look at what the weather/winds can do. The extra power of a rocket may just delay your impact a little... The extra power of a turbine might not even be sufficient in some cases. I guess my point is more that its very wise to take a class in mountain flying and spend some extra time going over winds and prog charts prior to mountain flying. The more power the better, but it won't make you invulnerable by any stretch of the imagination!

[mikefox]

Well maintained grass strips are fine if your soft-field technique is good! I have flown into many in the US and Canada, as well as a few good dirt strips in Mexico (airplane just needs a wash when you get home!)

I always drag the strip first to check general condition - well worth the time and gas, though I doubt you could see a gopher hole!

[201er]

While on the topic, what is the proper soft field landing technique in a Mooney? Is it the same as in any other plane? Do you put in full aft trim to help you keep the weight off the nosewheel? Do you try to roll with the nosewheel off the ground or on the ground but with the weight shifted back? I never bothered trying this sort of stuff cause I never thought I'd take my Mooney off pavement but this thread is making me think otherwise.

[Hank]

When I visit grass, I try a little harder to be slow on short final. Most of my landings are with the stall horn squeaking. Do try to hold the nose up after touchdown, but grass decelerates the plane quicker so don't expect a long time.

I generally taxi with Full Up on the elevator, and keep the speed slow. Takes more power and higher RPM, but usually not much more than a fast walk. Expect to play with the throttle to keep moving. Our beach trips are all to a grass strip, 3500' with a displaced threshhold, coming in over pine trees that hide power lines to a substation beside the runway. Slow is good, low is bad . . .

[M016576]

An AOA gauge would really help (simplify) any sort of short/unprepared surface landing... Thinking out loud here...

[aaronk25]

I landed on a grass strip well I should say ice strip because it was last sat here in Minnesota and was -10f here in mn. Frozen plowed runway of grass feels like landing on glare ice.........was a blast. Forget steering with the nose wheel keep yoke back and steer with the rudder. Wheeeeeeee!

[fantom]

I landed on a grass strip well I should say ice strip because it was last sat here in Minnesota and was -10f here in mn. Frozen plowed runway of grass feels like landing on glare ice.........was a blast. Forget steering with the nose wheel keep yoke back and steer with the rudder. Wheeeeeeee!

 

.....or steer and stop using the suction generated from your pucker factor   

[rbridges]

A lot has been written on this board over the last year so you should search out these topics. The general consensus is that any of the short body Mooneys (pre-J or -K) are perfectly fine on grass. The mid-body J is generally fine, although you may want to have the inner gear doors removed if you're going to land on any rougher or high-grass strips. 

 

that's the biggest reason I don't land on grass.  Those inner gear doors are crazy expensive for what they are, and I don't want to risk damaging them.  And yes, I'm too lazy to remove them.  

[fantom]

that's the biggest reason I don't land on grass.  Those inner gear doors are crazy expensive for what they are, and I don't want to risk damaging them.  And yes, I'm too lazy to remove them.  

 

Actually removing one takes all of 5 minutes, but if when you run into the home of the guy below gear doors will be the least of your problems.