PT20J

Thanks, Ross. Nothing beats a real test! Skip

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I have a KC 191 065-0054-03 SN 32144. MODS 6-11, 13-16.

GFC 500 will fly TRK or HDG.

Hopefully all the rebuilt ones include the stops which offer some protection.

Then, I would consider sending the mag out for service. I had a Slick mag with only about 200 hrs since new that was dropping about 250 rpm during a mag check. Timing checked twice and was correct. Drops less than 100 after I sent it to Aircraft Magneto Service for IRAN. Skip

Apparently, there are variations…

Skitter and dance? Sounds like a new disco move. Let's think about this... A lot us learned to fly in Pipers and Cessnas and were taught a couple of techniques that don't work as well in Mooneys. Normal takeoffs: Most of us were taught to wait for some particular speed and "rotate" to a takeoff attitude. (Rotation is really a jet thing, but let's ignore that for now). That works in planes that sit flat, but the Mooneys sit tail low. My M20J sits on the ground at 5 deg ANU (aircraft nose up). The normal climb attitude is 7 deg ANU, so there is not a lot of "rotation" at takeoff. But with the nose high attitude, the Mooney wing starts generating a lot of lift earlier in the takeoff roll than the trainers and if you wait too long to "rotate" it gets light on the mains and does the skitter and dance thing. Bob's 5 lb pull avoids all that and lets the airplane just gracefully leave the ground when it's ready to fly. Crosswind takeoffs: Most of us were also taught to hold the airplane on the ground with forward pressure longer than usual before rotating in order to get a rapid and clean liftoff and avoid any tendency to settle back onto the runway perhaps with sideways drift. But if you try to hold the Mooney down as it gets light on the mains, you transfer weight to the nosewheel and this can easily lead to a wild ride a.k.a. wheelbarrowing. I find that Bob's method gives me clean enough liftoff even with winds that it's not an issue. But, if you are worried about it, try taking off flaps up. This will reduce the induced angle of attack and the airplane will act more like the trainers. True, the liftoff speed will be 5-7 kts higher and you will use more runway, but the airplane is accelerating pretty rapidly as it nears liftoff speed and you'll likely only need another 100' or so. I've never measured it. With regard to bumpy runways, there is not much you can do about that. The Mooney stiff suspension doesn't help. It's like a rough water takeoff in a seaplane -- you have to "fly" the elevators on the ground as best you can to smooth things out as much as possible. Just don't overdo it, and if you do get launched into the air prematurely, just keep a slightly nose high attitude so that it doesn't come back down on the nose wheel. Skip

Not your fault. Sounds like maybe the gear swing was done with the doors attached and probably everyone was watching the gear and not the rudder. It would be difficult to see an interference with the steering horn/linkage with the doors on. I believe the service and maintenance manual calls for checking the rigging with the doors off after replacing the nose gear. Anyway, it should be easy to figure it out as Rich suggested above. Skip

I've never had this apart, but the indicator is a plastic rod glued to the end of the cable. I recall seeing some threads on MS about fixing it. Perhaps @carusoam remembers what to search for. In the mean time, you can set the trim so that the elevator is in trail with the stabilizer and that will be takeoff trim. Skip

SureFly is timed to engine at TDC. Advance is set by DIP switches. Sounds like maybe it was mis-set for 25 deg. Skip

I don't have any problem with a steeper approach. The biggest issues I see with people that are having trouble landing is flying too shallow an approach and not shifting their gaze toward the far end of the runway as they fly over the threshold. Either of these habits make judging height much more difficult. Mooney pilots seem obsessed with approach speed, but, within reason, it's not that critical. If you are a little fast, you just float longer and just need to be patient. True, if you are trying to shoehorn it into a 1500' strip, you better be on speed, but with a normal length runway, just be reasonable. At approach speeds, the airspeed stability is lower and it takes a lot of work to keep the speed within a knot or two. A steady glidepath is more important than constant airspeed. Skip

Higher rpm = more power Lower rpm = better efficiency, to a point. At higher rpm there is more tip loss and at lower rpm the angle of attack is not optimum. So, there is an optimum point. But, the whole point if a constant speed prop is to make that optimum broad, so we’re not talking about a big difference. Bob Kromer once said that Mooney optimized the M20J prop for 2500 rpm. David Rogers analyzed Bonanza props and came up with a rule of thumb that the optimum rpm is in the range of 14 to 15 times KTAS. https://www.nar-associates.com/technical-flying/propeller/cruise_propeller_efficiency_screen.pdf Skip

I’ve noticed that people that work on their own planes a lot complain a lot less about what shops charge.

My 1994 M20J was reweighed last year after the new Garmin panel and came out at 1895.3 lb and CG 46.03”

Probably not. Depends on the type of battery. If it is a Concorde AGM, it is recommended to charge it at constant voltage and as much current as the battery will take.

I thought that too, until I did it once

Mooneys are pretty nose heavy. When we weighed my M20J , it had 639 lbs on the nose wheel. I've never noticed that taxiing with up elevator does much except make my arm tired from fighting the trim bungies.

The most common cause seems to be forgetting to latch the baggage door. Usually, they pop open during the takeoff roll just before rotation speed. The latch pushes the pins out and you cannot depress the latch handle fully unless the pins engage the holes in the frame, and locking it adds no security because the latch is an over-center mechanism.

Bob Kromer conducted flight tests (in an M20K, if I recall correctly) with the airplane rigged to allow him to open the door in flight and found no problems. However, there are reports of the door coming off when it opened in flight. I think Bob tested an new airplane and over the years the piano hinge can wear a lot. So, it's probably best not to test it. Locking the door is a good way to make sure that you don't leave it unlatched. However, locking it only locks the external latch and does not affect the emergency unlatch mechanism, so if that is not latched properly -- or if the cover is missing and something in the baggage compartment snags it -- the door can still come open. Skip

I didn't know about the AD because it came out long after I had sold my 1978 J. But I remember replacing that gasket twice. Sounds like even after complying with the AD it would be good to inspect carefully at each oil change and keep a couple of spare gaskets on hand. Skip

Go here and enter 2002-12-07 in the search box https://drs.faa.gov/browse Skip

A large part of the break in happens in the first couple of hours. Lycoming ran my rebuilt engine in a test cell for about 2 hours, and I never saw elevated CHTs.

The IO-360–A3B6D has an adapter for the spin on filter that has a rubber gasket attached. The adapter is attached to the accessory case by the threaded nipple that the filter screws onto. Sometimes the filter sticks to the adapter and causes it to loosen. You should remove the adapter and check that the gasket isn’t damaged. Skip

Some thoughts on Mooney flaps: Flaps do three things: 1) They increase the effective angle of incidence which results in a lower body angle, 2) They reduce stalling speed allowing a slower approach and landing, and 3) They increase drag allowing a steeper approach. Mooney flaps are single slotted and have a wide span affecting most of the wing. They are more effective at reducing stall speed compared to many other single engine airplanes, but they produce less drag than some others making it harder to get the Mooney to slow down if you find yourself high and fast on final. I think that's the main reason speed brakes are a popular option. If the wind is really gusty and the runway long, I use less flaps. The reason is that I want a higher approach speed so that the gusts are reduced as a percentage of my airspeed. However, this is not strictly necessary -- it's just a preference. In gusty conditions, the airspeed will wander around and I set pitch and power so that it bottoms out at my desired approach speed. Skip