Porsche Mooney N137MP 

 

Performance? I flight plan for 155 knots TAS, about 5 knots faster than my 201. I didn't run my 201 hard, and don't run my PFM hard.

Surprises? Don't leave your master on.  Remember, this is an all-electric airplane.  Instruments are electrically driven and not cheap.  When I left my master on, I burned out my flight director as the gyro spun until my battery ran down.  Cost for repair $3500 for a rebuilt unit. A new one was $10 000. Ouch.

Support? I'm always a little scared...  Gary Butcher at Porsche has been fantastic.  He knows the PFM inside and out.  If you don't get him on the first call he'll call you back within hours.

Wittenbrook Flying Services in Barnsville, Ohio, Mooney experts with PFM training, have provided all maintenance with no problems, but about $300 more expensive for annuals than my old 201.  On my last trip they installed the free-from Mooney upgraded heater.  The old one was barely adequate.

If you don't have a PFM-qualified A&P mechanic near, Gary has offered to fly in and train your local A&P for airfare and lodging.  Now is that support, or what?

Would I purchase another one? You bet. It's not all that much more than a 201 the same model year, the features are light years ahead, and I love it when a tower operator asks, "Is that a Porsche?  Nice airplane."

Rodney Cobb N137MP.  Aviation Consumer 1994

 


 

 

“Porsche has built aircraft engines for over 75 years. This engine is based all on 1980’s technology versus 1940 technology done over and over by Lycoming and Continental.”

Darrell Duchesneau, defending the Mooney PFM design in letter to MAPA Log, Sept/Oct, 1994

 


“It took the dumb out of the pilot when the pilot was so inclined, and left him to concentrate on the far more important task of flying the airplane.”

 

 

Mark Twombly referring to the Mooney PFM (Porsche) engine and its replacement of mixture/prop/MP controls with a single control, AOPA Pilot, 1996.

 

 


 

“It was a dream machine for hands-on pilots.”

 

Mark Twombly referring to the Mooney PFM (Porsche) engine and its replacement of mixture/prop/MP controls with a single control, AOPA Pilot, 1996.
 
 

"When Pam and I traveled to our first Parade in Dallas/ Ft. Worth in 1987, A Porsche Mooney was there giving rides. We had to meet up at the airport, sign the waiver , and were one of just a few there taking this opportunity to fly in it. We were thrilled !
Flew over some awesome pasture land, scattering a few Texas longhorns for good measure. A gorgeous day.

The sound , as Chuck suggested, was totally ethereal. When on the ground looking up, that Baby just sang like a 911, but you were hearing the sound over you and around you, not from a car on the ground.
We got to stay up an extra stint, because there weren't any riders waiting . Our Pilot ??? Who would have believed......he grew up in ND about 12 miles from the farm where I grew up !

At the Colorado Springs Parade, in 88, the word was out........the length of the line-up was atrocious......several hour long wait. We wish now we would have hung around and went again, as the sound overhead sent chills up your spine when they flew it over the Parade site.

But at the Michigan Parade in Traverse City we went again.

The pilots all raved about the craft, the engine, the whole deal. The plane was as smooth as silk.

Great memories.....Thanks for bringing them all back again."
 
 

 


When we flight tested and certified the PFM in 1988, we were concerned for the somewhat sluggish takeoff and climb performance that the PFM 3200 engine/prop combination exhibited.  The PFM airplane was certainly certifiable, meeting all climb performance requirements per FAR Part 23.  But the airplane did not climb like other Mooneys.  Max power static thrust was low at lower airspeeds due to the slow turning, wide chord, two-blade propeller.  This resulted in initial climb performance being anemic until accelerating to 100 KIAS or so. At 100 KIAS and above, static thrust would dramatically increase and the airplane would climb out rather well (800-900 fpm on a standard day, max weight).

Three things this PFM pilot should check or do: 1) Check for proper engine operation so maximum power is being developed at full throttle.  This means maximum RPM, manifold pressure and the correct fuel flow.  It's hard to find a mechanic who knows how the properly set up a PFM 3200 engine.  This one sounds like it is way low on power. 2) Fly the airplane a little differently.  Lift off, retract the gear with a safe, positive rate of climb and then allow the airplane accelerate to 100 KIAS or so before pitching up for the climb, 3) Keep the fuel load adequate for the mission, but don't carry unnecessary fuel for the flight at hand.  Weight seemed to affect the PFM's performance more than the other Mooneys we flight tested.  The PFM carries a lot of gas - well in excess of what is needed for most flights. Managing fuel loads in the PFM will pay back big in better takeoff, climb and cruise performance.  Tankering fuel in the PFM really diminishes performance - much more so than the other Mooneys.

Just some thoughts from the Mooney/Porsche flight test program for any PFM pilots left out there.

Bob Kromer

http://members.cox.net/mooney.faq/PilotBob.html

 


 

 

  1. R. Zephro Says: 

    The PFM was/is a great airplane to fly. It was back in the ’90′s that Ken Shoup of All American had a PFM and a Mooney Turbo 231 for sale and I had a couple of guys inbounding from Alabama to buy one of them and wanted to fly in both to compare… Shoup had the 231 stored at Stinson on the South side and we were at AA’s office at SAT, so Shoup sent me to fly the PFM over to Stinson with the two other big guys aboard. It was a hot summer day here and about 105 degrees. I had mentioned to Ken that I had zero PFM time and he said to just push the throttle control in to go and even full out (idle) if I wanted to come down quickly. No shock cooling of this engine due to the 911 fan by Porsche. I got a kick out of starting that bird. Way more like a car than a plane! Wow, she sounded bad-ass from within the cockpit, so I gave her a testosterone rev or two and off we went to the active. The PFM did not have much useful load numbers, but why I don’t know. We were a bit over gross and on a hot day, she got off quickly and immediately went to about 1100 fpm minute climb and stayed there until I got 3 to 4,000 feet, my assigned altitude. We flew her a bit and had fun doing so as we were all impressed! After arriving at Stinson and pulling the 231 out of the hanger, we took off with about the same fuel load and only got 5-600 fpm that day even though we were weight legal. It was a hot day and fully understandable, but compared to the non turbo’d PFM’s over gross rate of climb? Sick!
    Shoup had gotten several PFM’s to sell and I was selling of his inventory as well as mine in those days, so I was able to garner some experience with the PFM. Porsche was hoping to eventually get a 3-4,000 hour TBO, so they sent one of their engineers around to the planes to do a free top overhaul just to see how things were progressing. None of them really needed a top that I was aware of and I sure bent that mechanic’s ear. His first name was Bill and his last escapes me at the moment, but Bill knew his stuff! He also told me that they hoped to make a higher horsepower version with a turbo and that was exciting to hear. I really loved that engine to spite hearing about an occasional engine failure in the vicinity of certain microwave towers, but they fixed that straight away so I was told.
    I love Mooney aircraft, but the problem Mooney suffers and has suffered in its past has been in my opinion poor marketing to spite being the best product out there by far. During the ’80′s, people were coming out of flight schools by the droves and many bought airplanes; usually what they learned in, the Cessna’s. There should have been a PFM parked centrally advertising a free ride to flight school graduates so as to show them what a “real” airplane is and how easy the PFM is to fly. How could the PFM compete when it was priced a bit higher than the flagship 252? Couple that with having to change out prop blades every 1500 hours as well as overhaul the gearbox to the tune of around $5800.00 in ’80′s money, and some thousands for the composite blade replacements, well, they set their own death by trying to advertise and compete with airplanes they were already producing.
    The PFM had greatness, just overlooked some. I would personally consider operating a PFM as experimental just to keep that great 911 engine purring under that jet-sexy bonnet of the PFM.
    zef