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Performance issue M20J


BettyFord

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Hi, I am planning to buy a M20J. As I am based at an airport with 2200ft gras strip I was interessted in the takeoff performance of the Mooney. Consulting the poh I found on a standard day at 800ft elevation the M20J from 1982 needs about 1200ft takeoffrun.
Now I found a MSE from 1995 wich is allmost the same aircraft, but has a little more max t/o weight. To my surprise the poh says that the takeoffrun with max t/o weight is now 2200ft! Allmost twice as much and with my short grasstrip I will get in trouble when the weather gets hot!
Can this be true or what am I doing wrong?

Thanks

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I have a 1978J and am off the ground on pavement almost always before 2,000 feet. However, a 2200 foot “grass” strip would not fit my comfort zone but would most likely work with ZERO safety margin built in.  A 172, 182, and 206 would have better safety margins for that length of runway and being grass.  I’ll defer to others who have more grass runway experience and their more qualified advice.

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46 minutes ago, BettyFord said:

Hi, I am planning to buy a M20J. As I am based at an airport with 2200ft gras strip I was interessted in the takeoff performance of the Mooney. Consulting the poh I found on a standard day at 800ft elevation the M20J from 1982 needs about 1200ft takeoffrun.
Now I found a MSE from 1995 wich is allmost the same aircraft, but has a little more max t/o weight. To my surprise the poh says that the takeoffrun with max t/o weight is now 2200ft! Allmost twice as much and with my short grasstrip I will get in trouble when the weather gets hot!
Can this be true or what am I doing wrong?

Thanks

It's not a "little more" weight, it's a 160 lbs increase to 2900 lbs gross weight with the same 200 hp in the standard M20J.  It's actually one of the lowest power/weight ratio of all the M20's, and that substantially eats into climb and takeoff performance.

The M20E's seem to have the best power/weight ratio, so if you're limited to a short grass strip, that might be worth considering

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I own an MSE 96’ and I can tell you it is substantially longer takeoff run then a standard j. I’d be much more concerned with landing performance. I’ve been in and out of a 2800 ft grass strip multiple times last year and it’s ok as long as everything is a ok. Crosswind, wet grass, etc. I wouldn’t even try it. The thing I notice with any mooney is on landing they don’t “stick” to the runway the way a Cessna or piper can. So you have to slow down a bit before you can really get on the brakes. I’m sure a great pilot could operate a mooney our of short grass strips but that way out of my skill level. 

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I didn't want to create a new grassstrip discussion. I just couldn’t believe that 160 pounds leed to almost double the takeoffrun distance. I thought that my calculation were wrong.

I would expect about just under 1500 on pavement, so that doesn't sound right. Suggest double checking to make sure you're not comparing runway run distance in one to clearing a 50' obstacle in the other.


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I live on a 3000’ grass strip with 70’ trees at the runway threshold.   The takeoff run in my ‘92MSE is considerably longer than my previous ‘78J, though I can’t recall the exact numbers. Landings are not an issue even on wet grass.

I never takeoff at gross weight from this strip.  I’ve developed procedures for different conditions unique to our runway such as max 10 knot tailwind on takeoff (it’s a one way runway), no more than 2600 lbs above 75F etc.

Ive found my takeoff numbers are almost right on the published values for paved runways and about 10% more than the published 50’ numbers.  This based on about 50 takeoffs where my wife would note the ‘break ground’ and ‘clear of the trees’ points.  I had to correlate her measurements to the runway because she would say “at Kelly’s bbq grill”, or “at Harold’s boat”.  Sometime Harold moved his boat which messed with my numbers!

lee

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5 hours ago, TomR said:

The thing I notice with any mooney is on landing they don’t “stick” to the runway the way a Cessna or piper can. So you have to slow down a bit before you can really get on the brakes. I’m sure a great pilot could operate a mooney our of short grass strips but that way out of my skill level. 

Raising flaps will help stick to the runway. Soon as you touch down. In my Mooney, I can hold the throttle to idle, extend one finger and raise flaps. Those with a slider on the right instead of a push-to-hold switch don't have it so easy . . . .

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9 hours ago, BettyFord said:

Hi, I am planning to buy a M20J. As I am based at an airport with 2200ft gras strip I was interessted in the takeoff performance of the Mooney. Consulting the poh I found on a standard day at 800ft elevation the M20J from 1982 needs about 1200ft takeoffrun.
Now I found a MSE from 1995 wich is allmost the same aircraft, but has a little more max t/o weight. To my surprise the poh says that the takeoffrun with max t/o weight is now 2200ft! Allmost twice as much and with my short grasstrip I will get in trouble when the weather gets hot!
Can this be true or what am I doing wrong?

Thanks

If I was based at a 2200 foot grass strip or hard surface strip, the Mooney wouldn't be my airplane. If everything is executed perfectly every time you'll be fine but we all know that everything isn't perfect all of the time. I would want much more margin of safety than that. A Cessna 182, in my opinion, would be a better airplane for that field.

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You don’t do a 2200 takeoff roll on grass.  You use soft field technique, which means that you keep the yoke full back and pull the plane off the ground and into ground effect as soon as possible.  In my 231 that is 1,000 feet or less.  The rest of the way, you stay in ground effect but off the runway until you reach rotation speed or a little more.  All that is required for the “in ground effect” part of the maneuver is good ground, i.e. not bushes or tall grass. Your wheels are not on it.  I have landed on all but one of the 22 grass strips here in MN, and most of them are built with a flat “runout” area for this reason.  That said, it would not be my idea of fun to regularly operate out of a 2,000 strip.  My personal limit is 2,300, and at that, I need to get in some short and soft field practice before I try it.  Landings are shorter on grass also, the friction of the grass will slow the plane much faster than asphalt.  The problem is, you are a test pilot and quite alot depends on having and applying very good technique.  The other problem is that all this works fine in normal wind conditions, but in gusty crosswinds when you might need more speed for rudder authority, you would be asking for trouble.

I guess I don’t see how or why a Mooney fits into this picture.  Mooneys are traveling machines.  Four hours from Minneapolis to the Rockies.  If you want to lark around on grass fields get a high wing taildragger or at least a Slowhawk.

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I landed a Bravo on wet grass at Canadian strip at 4500 ft elevation 80 degree day.70 ft trees to clear at approach end..with nil braking due to tires breaking traction it took all 4000 ft to get stopped.Two days earlier ,a chartered piper lance ran off the end with moderate damage to prop and cowling.2000 ft grass strip equals not based there

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Yes you will have a longer roll out at altitude airports.  I think you will find that most if not all airports out west take that into account.  Most of our rural runways in the midwest are in the mid-3,000’s, which is plenty of room.  Leadville is 6,400 if I recall correctly. The small strip at Taos is 5,500.  I don’t think I would land a Mooney on wet grass.  I was doing landings on grass in my 231 quite often for a couple of years, but always avoided any wet conditions.  Was not concerned about the braking as much as the ground conditions, ruts etc.

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Welcome aboard, Betty...

Many people around here operate Mooneys on grass strips.

The nicer the grass strip has been cared for, the better...

But, we have one pilot that has posted videos and pics of operating his Mooney from an unimproved farm dodging large cows...

As far as performance numbers go, the modern POHs have done a good job of graphing T/O and landing under various conditions...

Anyone doing this type of max performance T/O and landing has maintained good landing skills which requires good speed control in the traffic pattern.

T/O runs in airplanes is directly related the power to weight ratio.   High and hot requires more hp available compared to low and cold...

This challenge is often discussed as a high density altitude (DA) take-off.   

Modern technology helps us actually measure the combined skills of our plane’s and pilots.... a portable WAAS /ADSB device combined with an iPad app can let you practice and measure all of this before going to a short and grass field....

The plane doesn’t know it is doing something dangerous, only the pilot can know before he/she goes...

From a Safety point of view... many pilots want to be off the ground by the halfway point... this allows time for a decision regarding full power to continue on, or full braking to get stopped....

If your home field is only 2,000’ long, you want to plan all the engine failures that can happen... And all the decision failures that can happen...

High DA take-offs are closer to the edge of all the charts and graphs.  Loading the seats and the tanks has a similar effect of getting closer to the edge of the charts and graphs....

An example of how 10% more HP affects the T/O run... the Ovation normally has 1,200’ T/O run when lightly loaded.... the same plane with only 10% more hp (310hp in place of 280hp) has a measured T/O run of 800’...

Focus on the power to weight ratio and DA... when reviewing your calculations...  DA affects power generation and the ability to generate lift.  Independent of who built the airplane...

Small retractable wheels have a tendency to not work as well as large balloon tires on soft fields...

See if you can get some Mooney flying experience... you will be surprised with how much capability it has... and how quickly you can get the experience required to fly it well...  look for the words Transition Training...

Transition Training prior to buying a plane, may make a lot of sense for you...?

privare Pilot thoughts only, not a CFI...

Best regards,

-a-

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Today I was flying a M20J for the first time. And what shall I tell you. All the time I wastet in Cessnas and Pipers! IThe Mooney is so great fun. The ac is so agile and responsive quick and easy to fly. I neeeeed one!

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4 hours ago, BettyFord said:

Today I was flying a M20J for the first time. And what shall I tell you. All the time I wastet in Cessnas and Pipers! IThe Mooney is so great fun. The ac is so agile and responsive quick and easy to fly. I neeeeed one!

BettyFord, after reading all of the posts on here about basing a Mooney J at an airport with a 2200 grass strip, if you decide to go ahead with it, you need to spend at least a month of "transition training" here:  http://www.hazeldenbettyford.org/locations/betty-ford-center-rancho-mirage

:D

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