PT20J

OK, here’s the scoop on control bearings: My M20J IPC does not list the bearings but only the next higher assemblies which are brackets with the bearings pressed into them. I confirmed with Dan Reisland at LASAR that the aileron, elevator and rudder bearings are PN3A. (I did not confirm, but believe that the flaps use PN4A bearings). I confirmed with Ivette Prerez at RBC Bearings that they are NOT sealed. Therefore, the Mooney Maintenance Manual is correct and the bearings should be oiled with a light machine oil annually/100 hrs. Skip

Maybe, but on my J, they fit perfectly after installation and then got a couple of small puckers after a few hours. So, I guess it could go either way. Skip

Not surprised they fit well. Guy die cuts them and makes his dies from originals he has obtained over time. If gaps are small and temps OK I wouldn’t worry too much as air pressure likely closes them during flight. Key to a good fit is stretching the material slightly during installation to get it to “lean” forward and inward. Even so, small gaps are, as Don says, inevitable. Skip

Bevan-Rabell is now Bevan Aviation. Haven't used them personally, but I know an FBO with a large fleet of C-172 rental airplanes that swears they keep his KX-155s running inexpensively enough to make upgrading the radios not cost effective. Skip

Not sure about this. I believe that Mooney uses PN3A bearings. I cannot find a spec sheet online for this. Closest I could come is Motion Industries listing https://www.motionindustries.com/productDetail.jsp?sku=02664850 which lists it as having an open closure. Maybe someone can find a full spec sheet. If it is unsealed, then light oil would make sense every 100 hrs. Skip

So, what did you ask, and what did they say?

One more thing... People sometimes get confused about whether slips are prohibited in the C-172. They are not. Cessna merely said in the POH: “Steep slips should be avoided with flap settings greater than 20 deg due to a slight tendency for the elevator to oscillate under certain conditions of airspeed, slip angle, and center of gravity loadings.” On the older models with the maximum 40 deg flap setting, there was also a placard stating “AVOID SLIPS WITH FLAPS EXTENDED”. Skip

A few things to think about: 1. Mooney changed the elevator trim design starting with the K model from the old trim assist bungees to a variable down spring. 2. So long as a maneuver is not prohibited in the limitations section of the AFM it should pose no undue hazard. 3. When an airplane is buffeting, it’s telling you something. 4. Kromer was talking about extreme sideslip angles with full rudder deflection. Smaller sideslip angles, used for typical crosswind landings and small glidepath adjustments, are a different thing. 5. Generally, I think of slips as a training maneuver and for glidepath control in aircraft that do not have flaps. Mooney’s don’t really need to slip much in normal operations and passengers generally don’t like them. Skip

Available on FAA website.

MIL-G-81322 (superseded by MIL-PRF-81322) is Aeroshell 22 MIL-G-23827 (superseded by MIL-PRF-23827) is Aeroshell 7 MIL-G-3545 (obsolete, superseded by MIL-PRF-81322) was Aeroshell 5 and you can use Aeroshell 22 LASAR sells10% moly grease for Dukes actuators. (You can't find a commercial grease with more than 5% moly). You can look up mil specs. at http://everyspec.com/ You can find mil-qualified products at https://qpldocs.dla.mil/search/default.aspx (you will have to get around the fact that this site frequently has an out of date SSL certificate) Aeroshell grease info: https://www.shell.com/business-customers/aviation/aeroshell/knowledge-centre/the-aeroshell-book/_jcr_content/par/textimage_1433441235.stream/1445042875796/e76780948490d28fdd9086517026d27c1442a76d/aeroshell-book-5greases.pdf Skip

Great idea. How about swapping the boost pump switch with the pitot heat while we’re at it. Makes it harder for someone to steal the plane

The flap system is pretty simple. It comprises a motor, a control panel switch, some relays to reverse direction and some limit switches. In this application, the diodes are“flyback” diodes placed across the relay coils to snub out the induced voltage when current is cut from the relay. The 1N4004 diode was(is) a common general purpose diode. It’s rated at 1A forward current and 400V reverse voltage. It is very unlikely to be the source of your problem. Since the motor bench checks OK, it most likely is either a relay or micro switch.

Check all the wiring for loose connections. There are three wires to the transducer: power, ground and signal which should be shielded with the shield only grounded at the EDM 900. You can try soaking the transducer in Hoppes #9. It helped mine for a few hours but ultimately I ended up replacing the transducer. Skip

Ah, Fisk. First time was 8/3/81 - first day of the controller strike (the one where Reagan fired them all)! Didn't know what to expect, but the striking controllers showed up for Oshkosh, and all went well. Wife's most vivid memory is the jumbo-sized mosquito repellant for sale in the on-field store. Also recall the sound the sleeping bags made as we peeled them off our damp skin in the morning.

Interesting. Hadn't thought of that.

I used to be based at San Jose CA which is just a few miles inland from the Pacific ocean and never did anything special, and no one else there did either. The seaplane company I sometimes fly for operates in salt water all day long with a fleet of Otters and Beavers. At the end of the day we just haul them out of the water and wash them with soap and water. Skip

If I were troubleshooting this, I’d start by understanding mechanically exactly what caused the right flap to be “slightly loose” and exactly what was done to fix it. The mechanical design is not robust. Limit switches are connected to the mechanical system. Could be something got bent. Anyway, I’d eliminate that possibility first.

Max L/D speed is the speed for minimum descent angle, (i.e., best glide). Minimum sink occurs at CL3/2/CD max. which works out to about 3/4 of best glide speed. Best ROC occurs where there is the greatest spread between thrust power available and power required. Best angle of climb occurs at the speed where there is the greatest spread between thrust available and thrust required. So, best climb speeds are dependent on aerodynamics as well as engine power and propeller efficiency. Good references for aircraft performance: Dole, Charles E., Flight Theory for Pilots Anderson, John D., Aircraft Performance and Design Skip

Best glide occurs at the angle of attack for L/D max. In unaccelerated flight, L = weight, so best glide occurs at minimum drag which is the point where induced drag = parasite drag. If you reduce the parasite drag, the minimum drag speed should increase. Also, since lift = weight and the angle of attack for best L/D is a constant, the airspeed must increase as the square root of the weight increase to maintain constant lift. Thus, the best glide speed increases with weight. We hashed out prop stopped vs. prop not stopped a while back. The results from an old NACA study and some Youtube flight test videos showed that prop driving engine at flat pitch has most drag, prop stopped almost as bad (due to flat plate area of stopped blades), prop in high pitch better and, of course, feathered is best. Skip

Let's take the sunvisor example since that might be even more ridiculous than a landing light (but it's the same rationale) Rosen designed a new, improved sunvisor. Only "approved" parts can go on a type certificated airplane, so how does Rosen make it legal to install it? The part wasn't made by Mooney (holder of the type and production certificates). It doesn't conform to Mooney specs, so a PMA authorization doesn't apply. It's not an owner produced part. There is no applicable TSO. It's not a standard part like a nut or bolt. So, it gets installed under an STC. That's the authorization that allows it to be installed. And the FAA considers STCs to be major alterations by definition and requires a 337. I installed Rosen visors on my previous and current Mooneys. I did not file a 337 for the first plane and doubt that anyone has noticed in the 20 years since I sold it. On the current plane, I decided to keep it "by the book" and paid an IA $100 to inspect my installation and file the 337. It's up to everyone to decide how "by the book" they want to be (I've obviously been inconsistent). Still, I think it's good to understand the FAAs rules and policies. That's my only point. Skip

Well, as you pointed out, TSO-C30c is for position lights. I don't believe there is a TSO for landing/taxi lights. Without at TSO, you need traceability to an industry standard (such as the incandescents) or an STC (such as Whelen).

Every thread about LED landing/taxi lights seems to devolve into a discussion about what is "legal" to install in type-certificated aircraft. Here's a way to think about it: When the airplane left the factory, it was issued an airworthiness certificate. Every component in it was "legal." Now, a year later, if something breaks and you buy a replacement part from Mooney, it can be installed with a logbook entry and it's still legal. Suppose you leave your recognition lights on and melt a wingtip lens. You decide to buy a lens from LASAR rather than Mooney. The LASAR lens is manufactured under a PMA. This means that it has been approved as an acceptable replacement for the Mooney part and so it can be installed with only a logbook entry. Want to replace the Mooney sunvisors with Rosens? Well the Rosen visors are a different design than the originals so a PMA wouldn't apply. But, Rosen has an STC so they can be installed with a 337 and a logbook entry. Suppose you want to install an ADS-B out transponder. The transponder will be TSO'd which means that it meets a specification approved by the FAA for use in aircraft and so it can be installed with a 337 and a logbook entry. OK, so far? The FAA allows certain parts that meet established industry standards to be used on type certificated aircraft without a PMA or STC or TSO. Commonly cited examples are nuts and bolts and safety wire. Incandescent landing lights fall into this category. A 4522 lamp is made by several manufacturers to an industry standard, and they are interchangeable. Replacing one with another requires a simple logbook entry. There is no such industry standard for the LED replacements. This is why Whelen has an STC for the Prometheus lights. To be "legal", replacement of the incandescent lights specified by Mooney with an "equivalent" LED requires an STC'd part and a 337 and a logbook entry. You may or may not think this is reasonable. Your IA may or may not care. But that's the way it works. Skip

I'll look forward to a pirep from OSH. I too have an Aspen and I'm not interested in getting rid of it to install a GFC500. Garmin makes some neat stuff, but they don't always play well with others and I'm an open systems guy. When I talked to BK last December, they were still working on the first cert (Bonanza) and had no idea when that would be done, or when they would get to the Mooneys. I haven't talked to them since, but if they've completed all the planes listed in the marketing brochure (I notice that the wording says that the initial AML STC will cover, rather than does cover), then they made a lot of progress in seven months. It does seem that Honeywell is committed to this. I'm happy to wait for them to work out the bugs. When I was in tech, we had a saying, "The pioneers get the arrows." Skip

A good instructor is a great resource. But there are ways you can figure this out for yourself, and in so doing you will learn a lot about your airplane. Besides, it's a lot of fun to develop procedures that work for you rather than just using someone else's. A good place to start is to get a copy of Positive Flying by Richard L. Taylor and William M. Guinther (https://www.abebooks.com/book-search/title/positive-flying/). They are the ones that originated the PAC (Power-Attitude-Configuration) concepts used by many instructors, and the book describes in detail how to develop them. Happy flying Skip

Ah, the Texas hog tied look