PT20J

I had mine done this past spring at Sunquest in Everett WA. It took about 8 weeks. They do 40+ planes a year and do caravans for FedEx, Kenmore Air Harbor’s seaplane fleet, historic aircraft for museums and the Nordstrom family’s fleet among others. It wasn’t for CBs, but they took great care with the prep, layout, spraying and especially the touch up afterwards. My advice is to find a quality shop with a backlog of business and get on their schedule. They cannot afford to do a crappy job and screw up their reputation, and they cannot afford to take too much time since it screws up their throughput. Then, be prepared to pay what they want and ignore the posts that talk about how they got their airplane painted for $30K.

My only tip is that it gets easier every time you do it. The A&Ps advantage is practice — lots of practice.

My bad, I somehow missed the part about the light coming on after recycling the gear, so my comment about the breaker is not pertinent. You said you slowed down and did not get the gear horn. Did you pull the throttle back enough to be sure to actuate the microswitch?It depends on how it’s adjusted but it needs to go almost to idle. Also, do you know that the throttle switch/gear horn was working before this incident? It’s not something we hear a lot in normal operation. The gear up and down switches are DPDT. One pole of each switch controls the gear motor (through relays) and the other pole controls the warning circuits. It’s possible for one pole to be bad and the other good. The best (and safest) way to troubleshoot gear issues is to put the plane on jacks and ground power and open the belly. The good thing about Mooneys is that the floor indicator is mechanical and is the primary indicator. If it aligns properly, the gear is down. The lights and horn are secondary indicators.

The fuel tank pickups are above the sumps. That’s why there is unusable fuel. It would take a lot of water in the tanks to reach the pickups in level flight. Maybe less in a steep bank. There are coarse screens on the pickups to catch big chunks. Since the mechanic looked inside the tanks (presumably with a borescope) I presume these were checked. Some aircraft require adding a fuel filter between the Dukes boost pump and the engine-driven pump per MSB20-222.

Most likely the gear warning breaker tripped. Mine did that recently. It hasn’t done it again, so I have no idea why it tripped. That breaker powers the annunciator light, the floor light and the warning horn.

There needs to be some space between the knob and panel to ensure that the governor stop is limiting the movement and not the knob end.

I think the relays are only in the planes that have the takeoff position preselect.

Galling is microwelding caused by pressure and friction heating. Lube and not turning fasteners at high speed with a power driver will prevent it.

When mine did that it was a relay. Mooney used a couple of different relays. The original design used socketed relays that are available and easily replaced. The “improved” design (which I’ve been told by a well known MSC is no better) uses soldered-in relays making replacement somewhat more difficult

I agree with Ross @Shadrach. My 1978 J had one; my 1994 J does not. If I don’t get a greaser landing, the pitch down when the mains touch can bang the nose wheel down. It was much softer on the 1978 with the shock.

Good idea to remove it. It’s questionable to modify the wiring for the factory gauge if it is still the primary indication.

Is there a logbook entry?

That’s how I did it. When I put it back, I connected the ducts and wires and used some string around the ducts to hold the weight until I could get a few screws in and slip out the string.

The wemacs are glued in, but the duct tubing that connects to them has clamps similar to hose clamps (I replaced them with regular hose clamps when I reinstalled). So you can drop the headliner down enough to release the clamps and then remove it.

The heads in the two LASAR bolts don’t have the same markings. There may be a material strength difference. Anyone know what the concave depression in the nose gear bolt signifies?

The nose gear has three parts. The upper part is the truss, the middle part(which is the part that gets damaged by oversteering) is the leg, and the lower part is the spindle. But everybody seems to call the leg a truss.

Mod Works had a mod that worked really well. I’d try to find someone with pictures of it and copy it.

If the forward trim lead screw does not have the stepped stop nuts it can jam if enough torque is applied. The old BK trim servos have plenty of torque. I doubt a Garmin GSA 28 would do so. I don't know about others. Ks and later have a bob weight and variable down spring instead of trim bungees and seem to need a lot of nose up trim in the approach configuration. Also, because the elevator forces are higher in flare than many other airplanes, some have developed the habit of rolling in nose up trim to the stop during the flare (which of course exacerbates the nose up problem if you have to go around, especially after a bounce.)

So, it appears that the original POH indicating gear first was an error, later corrected by comment to agree with earlier versions of the POH. Interesting. Thanks, David.

It looks like a comment there in the pdf file. Mooney had been doing that rather than revising the documents and rolling the revision. What’s it say?

The horseshoe heading technique requires flying three headings exactly 90 degrees apart, so if your compass is off a few degrees on some headings then errors will be introduced. The NTPS technique only requires flying three legs at different headings and the exact headings don't matter. The only requirement is to hold the heading long enough for GS and TRK to stabilize. The NTPS spreadsheet allows entering four legs so that the solution is overdetermined leading to increased accuracy.

It's similar, but more general because it does not require flying a specific headings which may introduce compass errors into the calculation and errors if the headings are not held exactly.

The national test pilot school adopted this method and I believe that it is considered the gold standard. NTPS created a spreadsheet to automate the calculations. gps-pec-method.pdf GPS_PEC.xlsx

On my M20J with electric trim and electric flaps I find that the trim servo speed pretty closely matches the flap motor speed so if I actuate and hold the trim switch simultaneously with actuating the flap switch then the elevator force is minimal when either raising or lowering the flaps.

I think it depends. I looked up some from my library of flight manuals: Piper Arrow: Vlo/Vle 150 MPH, Vfe 125 MPH V35B Bonanza: Vlo/Vle 154 KIAS, Vfe 123 KIAS T-6G: Vlo/Vfe 150 MPH, Vfe 125 MPH DC-3: Vlo/Vle 144 KIAS Vfe 97 KIAS