M20K 231 - family plane?

[m20flyer]

The 231s look like a good value right now.  I'm getting more serious about buying and would look hard at a mid-body Mooney if the back seats are actually usable.

My experience is with an F model converted to a 201 (all the speed mods) and it was a decent hauler.  >1000 useful if I remember correctly.  I rarely had back seaters though.

Here's what I know:

• The -LB is more desirable, and I'd expect the -GBs to have been worked out by now.  If I find one with a -GB, should that be considered a dealbreaker?
• The earlier models and even some of the Js have SB208 for corrosion in the roll cage on the pilot side.  Are the 231s subject to this SB?  If so, how common is this problem on 231s.
• Takeoff distances and climb rates will work for the high-DA operations I expect to see (~7,500' @ 30*C near MGTOW; cruise into the teens but rarely into the FLs).
• It'll cruise 160-170 at 12gph or I can loaf around in on local flights at around 6gph.
• XC will be about 20% of the use, virtually all to high DA airports.  Local flights and currency will be about 80%.
• I can get insurance.
• I will rarely have to top the tanks for the flights that we intend to do.

What I need:

• 1,000lb useful
• Four usable seats
• Enough baggage space for light packers

Questions:

• How is the back seat legroom for people >6'?
• Are there any major gotchas for the 231 with an -LB engine?
• What are owners seeing as an all-in cost/hr for a 231?

Finally, if there is anyone in the Phoenix area willing to go for a demo flight, I'll buy the gas!

[hubcap]

I fly a 231, and it is a great traveling plane, but I believe other models fit your mission more appropriately. If 80% of your flying is going to be local, I don’t think you would need a turbo for that. Myrtle has a 950ish useful load. She does 150kts TAS at 10,000’ on 10gph and 170kts TAS at 17,000’ on 10gph. She has a lot of range with 72gallons useable. In order to take advantage of the turbo you need to use oxygen, so make sure you are comfortable with the cannulas.

[m20flyer]

O2 is not a problem.  We can do that.

DA at home is 5,000' on a "cool" summer day and closer to 10,500 on typical summer days at our usual mountain destinations.  I'm pretty much settled on a turbo or a 285-300hp NA engine in a 205/206/Cherokee6.

A 50% partnership would be ideal.

[PeteMc]

The 231 would be a good plane for you, especially at your base altitude.  Here are a few answers and thoughts.

• 1,000 lbs useful load is going to be pushing it.  After removing the vacuum system and the older radios I now have 902 lbs usable, that leaves 470 lbs with full tanks.
• Yes, all four seats are usable, but I don't know how it is for a 6'.  Everyone I've had in the back seat says there is plenty of room when the front seat people pull forward.
• You're right that there may not be many -GB engines left.  But if you find one, especially a high time one, that should drive the price down.  So use the -GB to do all your training, get extra hours for insurance, etc., etc. and just have in the plan to replace the engine.
• If the plane does not already have a Merlyn Black Magic Wastegate, you're going to want one.  You might also consider an intercooler, but not as critical as the Merlyn.

 

[natdm]

I don’t have a family but I’ve had some 6’ people in the back of my 231 and they said it was fine, “plenty of room”. 

My useful load is about 950 or so I think? Haven’t had to push it in a while. The CG is super forward though, which hasn’t ever been a problem. 

Absolutely love my 231, just wish Jimmy has set me up with a better pre-purchase inspection, as I’ve dumped thousands in to what I now know should have been caught. 

[Z W]

The 231 is a pretty good people hauler for a 4-place single.  Most have between 900 and 1,000 useful load but that number is deceiving when compared to other planes (even other Mooneys) due to its range, efficiency, and turbocharger.  I've been family hauling with one for a long time now.

As an example, if you do the math, on 50 gallons of fuel, you can fly up to 3 hours (with a 1 hour reserve) going 160 KTAS, which gets you 480 miles of range with a non-fuel payload of 660 lbs give or take.  Many planes with higher useful loads can't carry the same 660 lbs for 480 miles due to their higher fuel burn and/or lower speed.  In fact, as far as I can tell, you have to go to a 6-seat plane to do any better.

Then the turbocharger lets you actually use all the useful load at any airport on any day.  I've departed Telluride with two adults in the front, one teenager in the back, and 75 gallons of fuel on a 75 degree day, and it felt like a normal takeoff.

The rear seat space is fine for adults, after you do the dance to get everyone loaded.  If you have four adults, it's cozy, but you will probably end up doing shorter legs anyways.  I've found it's pretty rare that four adults have the flexible schedule required to take off and fly GA together for any distance.  If you have three, the rear passenger can spread out sideways and be very comfortable. 

[aviatoreb]

1 hour ago, natdm said:

I don’t have a family but I’ve had some 6’ people in the back of my 231 and they said it was fine, “plenty of room”. 

My useful load is about 950 or so I think? Haven’t had to push it in a while. The CG is super forward though, which hasn’t ever been a problem. 

Absolutely love my 231, just wish Jimmy has set me up with a better pre-purchase inspection, as I’ve dumped thousands in to what I now know should have been caught. 

I flew 6 and up year olds in my back seat and it was fine when they were small.  Its very cramped as they became 20 somethings year olds and over 6 feet but I have flow with the same used to be a 6 year old now 6'4'' who wanted to sit in the back holding hands with his girl friend.  Too small for that for a nice flight but it was superb when they were small.  When I got this plane I thought I would end up moving up to a larger plane when they got big but I never ended up doing that.  Now all 3 boys are all grown up - I drop my youngest off at college in Providence, RI in 2 weeks....  This plane serves me just great now on the other side and Im keeping her.  

[Pinecone]

You might want to look at a 252 with Encore update.  Mine is 1061 UL as of last weighing.

Also comes with auto wastegate and intercooler.

[natdm]

44 minutes ago, Pinecone said:

You might want to look at a 252 with Encore update.  Mine is 1061 UL as of last weighing.

Also comes with auto wastegate and intercooler.

Time to derail this thread.

Any idea how the 252+encore got a higher UL than the 231, which to my knowledge has less to weigh it down? Did something actually change or get taken out? Or did they just certify it higher after new tests?

[Pinecone]

1 hour ago, natdm said:

Time to derail this thread.

Any idea how the 252+encore got a higher UL than the 231, which to my knowledge has less to weigh it down? Did something actually change or get taken out? Or did they just certify it higher after new tests?

Encore upgrade gets you 130 pound GW increase.

[m20flyer]

2 hours ago, natdm said:

Time to derail this thread.

Any idea how the 252+encore got a higher UL than the 231, which to my knowledge has less to weigh it down? Did something actually change or get taken out? Or did they just certify it higher after new tests?

I agree!  I'd love one!  They're few and far between though.  I think there's one for sale now and the owner wants $200k.  Good for him if he can get it!

[m20flyer]

2 hours ago, natdm said:

Time to derail this thread.

Any idea how the 252+encore got a higher UL than the 231, which to my knowledge has less to weigh it down? Did something actually change or get taken out? Or did they just certify it higher after new tests?

What little I've read about it seems to point to an improved steel tube structure with larger diameter tubes (or maybe more structure?) near the wing attach points and beefier main gear units.  I have no idea if this is true.  It's just what I've gleaned from a couple articles.

Edited August 16, 2024 by m20flyer

[natdm]

42 minutes ago, Pinecone said:

Encore upgrade gets you 130 pound GW increase.

But *how*?

[Hank]

54 minutes ago, natdm said:

But *how*?

There are some airframe tweaks, beefier gear legs and different brakes. 

[natdm]

50 minutes ago, Hank said:

There are some airframe tweaks, beefier gear legs and different brakes. 

I guess that leaves me more confused as I'd think adding heft to the gear legs would weigh it down more. 

[kortopates]

they certified the plane for a higher gross weight, increased it by 230 lb, boosted the HP by 10 HP to 220, doubled the control balance weights to improve flutter resistance, changed the brakes to double pucks so that they last longer which required a change to the landing gear spindles without any change in weight (as i weighed them) - really not any beefier.
My useful load is over 1120 lbs

Then engines are a complete turbo with automatic hydraulic watergate and aftercooler unlike the manual watergate 231 (merlyn or fixed bolt are both manual) including tuned induction system and 28V system - very different from 231 and more $$.
Frankly the most efficient Mooney when cruising at altitude with much improved useful load. (Down low, the J earns that title )


Sent from my iPhone using Tapatalk

[N201MKTurbo]

18 minutes ago, natdm said:

I guess that leaves me more confused as I'd think adding heft to the gear legs would weigh it down more. 

There is more to the gross weight of an airplane than flying, Landing has a lot to do with it. You have to be able to slam a fully loaded plane into the ground without breaking anything.

[natdm]

35 minutes ago, N201MKTurbo said:

There is more to the gross weight of an airplane than flying, Landing has a lot to do with it. You have to be able to slam a fully loaded plane into the ground without breaking anything.

Then why am I practicing full stall landings?? 

Thanks for the help.

[Hank]

1 hour ago, N201MKTurbo said:

There is more to the gross weight of an airplane than flying, Landing has a lot to do with it. You have to be able to slam a fully loaded plane into the ground without breaking anything.

And get it to stop! Thus the larger brakes.

53 minutes ago, natdm said:

Then why am I practicing full stall landings?? 

Thanks for the help.

Because it’s a better way to land. But the plane has to be able to sustain higher speed landings, as in a 200' ceiling instrument approach, loaded, at 90 knots or more.

[N201MKTurbo]

1 hour ago, natdm said:

Then why am I practicing full stall landings?? 

Thanks for the help.

The cat likes them better.

 

[Pinecone]

5 hours ago, m20flyer said:

I agree!  I'd love one!  They're few and far between though.  I think there's one for sale now and the owner wants $200k.  Good for him if he can get it!

Then you would choke at what I paid for mine.  

The Encore conversion is about $15,000 in parts.

252 comes with 28 volt system and speed brakes also.   And the engine package is what the 231 should have been.

And nothing like 175 KTAS true on 10 GPH.

BTW, there are 6 listed on Controller right now from $174K to $275K.  One is definitely Encore converted, as it is advertised as a 1988 Encore.  The actual Encores are 1997 or so.

Remember, the purchase price is not really the major cost of owning.  And always, Buy Once, Cry Once.

OOOPS, one of the 6 252a listed on Controller is actually a 231 with the -MB conversion, sometimes called a 262.  

[Fly Boomer]

7 hours ago, m20flyer said:

I agree!  I'd love one!  They're few and far between though.  I think there's one for sale now and the owner wants $200k.  Good for him if he can get it!

He will get it unless there is something seriously wrong with the airplane.  I saw a J advertised recently for $300k.  That's right--1.5 times the ask on the Encore.

[m20flyer]

He could.  I'm learning the Mooney market.  Strikes me as steep, but I'll keep an eye on what moves.

I've been watching 205/206/cherokee6 sit for a long time due to fantasy pricing schemes. Maybe the Encore is a $200k plane.  Too rich for me in that case!

Market isn't what it was two years ago.

[Shadrach]

7 hours ago, m20flyer said:

I agree!  I'd love one!  They're few and far between though.  I think there's one for sale now and the owner wants $200k.  Good for him if he can get it!

Not at all an unreasonable ask depending on equipment and engine time. Encores are super nice and relatively rare aircraft. $200k is lower end of that market.  

The Encore is the ultimate Mooney in many ways, however, I am not sure it’s the best mountain mooney.  Most have empty weights between 2050 and 2200lbs. That puts them near the bottom of the Mooney power to weight ratio hierarchy.  We’re talking about 200ish horsepower airplanes. Turbo or no turbo, under most scenarios, the fatter the airframe, the more runway it’s going to eat.

I would urge you to look at book runway performance numbers for all the models you’re considering rather than making assumptions about performance.
 

You might also consider TN’d J or F model. Same size cabin, lighter airframes, less expensive to overhaul.  And both likely have better high altitude runway performance than of the K variants save for the Rocket.

 

[m20flyer]

I have the books for A-R models.  They use a good bit of runway for sure. Good rates of climb though.

I passed up a turbo F (all manual) a few years ago and regret it.  That would have been a nice plane.  Maybe a J is the way to go.  A TN J would be an excellent plane!

The mountain airports we use all have ~7,000' runways or better. The only exception will be Durango (00C) but that's still a 5,000' strip with a bit of a downhill slope.  My hard-IFR freight days are behind me and I'm willing to wait for favorable conditions.