PT20J

The mounting bases on the TCO wicks are riveted onto the control surfaces, but the wicks themselves screw into the base.

I have no idea (but it's an interesting question) but can't resist the irony that we would have to use a Russian system because we're jamming our own. Something seems backwards there.

Somewhere over central Texas, one of my elevator static wicks departed. I just purchased a replacement from LASAR ($47.14!). I notice that the new one comes with a #4 split lock washer. These are not installed on my other 14 wicks an not called out in the IPC. I'm aware that there is test data showing that split lock washers don't perform well in high vibration environments, but I'm going to install them on all the wicks under the assumption that they can't hurt and may help. Also, I'm checking that the wicks are screwed in tightly on my preflights from now on. Skip

There are a few things about oil consumption that I know, and a lot that I don't. What I know: Oil escapes by way of rings, valve guides, crankcase vent, leaks. You have to figure out which when chasing oil consumption. Some oil necessarily gets past the rings because the cylinder walls need lubrication or they will wear out more rapidly. As the walls wear, the cross hatching disappears. What I don't know: Why do Continentals seem to consistently use less oil than Lycomings? What's the best oil level for a Lycoming IO-360 for minimum consumption? Everyone seems to have their favorite. My experience with a lot of Lycoming 320-360 cu in engines over the years was to run them at seven and add a quart when it got down to 6. Many seem to find lower oil consumption with lower levels. I tried running between 6-7 for about 50 hours and 5-6 for about 50 hours after break-in in my Lycoming factory rebuilt IO-360-A3B6 and there was no difference. Does oil type (single viscosity or multi-viscosity) affect consumption? I recently changed from AS W100 to Philips XC 20W50 and in seems that the consumption has decreased, but it is too soon to have statistically meaningful data. I also added CamGuard to the Philips. Did that make a difference in consumption? (Hard to see how, but who knows?...) Here's a document I found a while back from AeroShell that states that "tighter engines" (I think he means cylinder to ring tightness) burn less oil on multi-viscosity oil, but he doesn't explain why. video-transcript-oil-consumption.doc Skip

Yep. The bunch that won't retract the gear for fear of needing it again drive me a little batty. It comes down pretty fast. Don Maxwell had an engine failure during a test flight, decided he didn't want to land straight ahead in the junk yard, did the impossible turn (made the tower controllers duck ;-) and was just about to touch down when he remembered the gear. Said it went clunk, chirp. Skip

The most efficient landing pattern is the 360 overhead, and the continuous turn to final is just 1/2 of that. I too like to put all the flaps in at the beginning of the descent -- it simplifies things and makes it easier to judge descent angle since the body angle isn't changing. Skip

For piston powered airplanes, there are two sets of curves necessary to define performance speeds: thrust required/thrust available, and power required/power available. One way to remember which set to use is that if a time element is involved, the power curves are apropos. Below are the formal definitions of a number of common performance speeds. Anderson, John D., Aircraft Performance and Design is a good reference. (Also, Anderson's Introduction to Flight is excellent because he explains concepts in a very straightforward manner). Less technical explanations can be found in Eckalbar, John C., Flying High Performance Singles and Twins. Vx = best angle of climb = speed where there is maximum excess thrust available above the thrust required for level flight. Vy = best rate of climb = speed where there is a maximum excess of power available above the power required for level flight. Best glide = speed for greatest glide distance with no wind = L/Dmax speed = minimum drag speed (since lift is a constant approximately equal to weight). At this speed the parasite drag and induced drag are equal and each comprise 1/2 of the total drag. This is also the speed for maximum range. Maximum endurance speed = speed for lowest fuel flow = [CL3/2/CD]max which works out to be L/Dmax x 0.76. At this speed, induced drag is twice the parasite drag and 2/3 of the total drag. This is also the minimum sink speed. Carson speed is minimum fuel flow per unit of velocity = [CL1/2/CD]max and works out to L/Dmax x 1.32 If you look at the thrust available and power available curves you will notice that the maximum thrust occurs when the airplane is stationary and thrust actually decreases with airspeed. However, the power available is zero when stopped (because no work is being done since the airplane is not moving). The power available increases with velocity. Skip

I'm not actually sure what is meant by "the wing being more efficient." Aerodynamicists use Oswald's efficiency (e) factor to correct for non-ideal lift distribution. But e is a fixed value independent of airspeed. Efficiency might best be represented by CL/CD max. But that's a fixed characteristic also. One thing that does change with airspeed is the propeller efficiency. Propellers designed to maximize cruise speed are most efficient at a certain rpm at cruise speed, so a higher climb speed will be more efficient than a lower one. Skip

Vy occurs at the airspeed where the power available in excess of the power required is maximum. It's best glide that occurs at minimum drag speed. But, it's fair to say that for a high performance airplane, climb rate is relatively insensitive to airspeeds several knots above and below Vy. The VSI is too sensitive to turbulence to accurately determine steady state climb rate -- it's much more accurate to use multiple timed climbs from +/- 500' around the desired altitude and average the results. Climb rate will depend on aerodynamics as well as engine power and propeller efficiency, so it's a bit complicated. Here are some interesting articles: http://www.mooneypilots.com/mapalog/powersettings.html https://www.advancedpilot.com/articles.php?action=article&articleid=1842 Skip

Here are a couple of examples to cheer you up... Fewer than 1700 DHC-2 Beavers were built; the last one rolled out in 1968. De Havilland Canada ceased operations in 1992. Yet hundreds of Beavers are still flying with many in commercial service in the US and Canada. Kenmore Air, Sealand, WhipAire and others manufacture PMA and STC parts. Viking Air owns the type and production certificates and also makes parts and currently is building new Twin Otters. If you can find a wreck, you can still get one rebuilt today better than new. There are still a bunch of North American P-51s flying. Cal Pacific Airmotive owns the type and production certificates and will build any part you need. With such a large fleet and high parts commonality, someone will step up to fill the void if Mooney can't. Skip

NACA

A '78J is a great machine - I used to own one. Don't feel bad about not having an engine monitor. A lot of folks here have them and have learned to use them to advantage. But, it's only another tool: Remember good mechanics diagnosed and fixed airplanes perfectly well before these things became common. It just takes a little longer. The J should climb fine full rich, cowl flaps open, 2700 rpm, full throttle. It won't be anywhere near detonation under these conditions. Engine roughness is caused by uneven power from the cylinders. The little Lycoming 4 banger only has four to begin with, each contributing 50 bhp at takeoff, so if one isn't pulling it's weight, you feel it. Assuming that the compression is good and the valves aren't burned (I assume the valves were checked with the borescope along with the cylinder walls) then it must be fuel, ignition or valve action. I'd clean the injectors, test the plug resistance and clean and gap them, and look over the ignition harness. If it's not fuel or ignition, it could be the valve action. Your mechanic can do a wobble test, measure valve lift and check the valve springs pretty easily and noninvasively. The thing to do is be methodical and through and check the simple things first. Skip

Early Js didn’t have the bump on the left side.

That is what I would expect. Glide ratio is numerically equal to L/D. Lift is fixed (it has to offset weight), so the only thing you can do is decrease drag and rotating the dead engine causes drag. The faster you rotate it, the more drag, so max pitch (low rpm) reduces drag. Rotating the engine requires power from the prop (which creates drag) in order to do the work of compressing air in the cylinders. Closed throttle = less air = less work done = less drag. Skip

Sounds like your measurements are pretty close to mine. When you run out of nose down trim, are you forward or aft CG and what's your airspeed? I've never run out of trim, but I've never looked at the indicator position in descent, so I don't really know how close to the limit it is. I'll try to remember to look next time I fly. Skip

I suspect some variation in takeoff trim setting is a personal preference issue. If set above the top of the takeoff range (forward CG) it lifts off with very little back pressure. But, you will need to trim nose down after it becomes airborne (before retracting flaps). If set within the takeoff range, it takes more pressure to lift off, but it will be in trim until you raise the flaps. I prefer the latter because I don't want it pitching up after liftoff at low airspeed close to the ground if I get distracted. Skip

Actually, there isn’t any appreciable force on the weld. The jack pad lifts on the solid horizontal rod. The short piece of pipe just keeps the jack centered on the rod. Skip

If someone disconnected the trim shaft for some reason and rotated the trim wheel before reconnecting, it can cause such a problem because the stops are at the forward gearbox, not the tail jackscrew. The trim indicator cable also attaches at the forward gearbox and can be set (by loosening a setscrew and sliding the cable) independently of the of the actual position of the empennage. Proper set up using the service manual procedure requires leveling the airplane and using travel boards. However, mine seems to be rigged properly and you can use my measurements above to check yours. Skip

When I asked Jimmy Garrison, he said there was no resale premium for an IO-390. I bought a Lycoming factory rebuilt IO-360-A3B6 which is on the type certificate (so it doesn't require an STC) and is less expensive. The most important improvement is the roller lifters which probably negate camshaft spalling and Lycoming puts that in every new and rebuilt engine nowadays so you don't have to get the IO-390 for that. Keep in mind that camshaft spalling hits your pocketbook but the engine will still run pretty well with a chewed up camshaft so it's not so much of a reliability issue. Also, keep in mind that if that engine has flown regularly and not been kept in a region of high humidity, it may be just fine. In fact, it might be the most reliable it's ever been, right now. If it has been serviced with Camguard, that may be a plus. If it has been serviced with Aeroshell 15W-50 that may be a minus. Skip

Looking through the Mooney IPC and Service Manual, it seems that Mooney used several different gauge clusters and transducers over the years. The early models used temperature and pressure transducers that were a simple variable resistance to ground type. Later models used more accurate wheatstone bridge type transducers, and some apparently required external amplifiers. I've never had to delve into the internals of the cluster gauges and I don't know what your setup is. Perhaps @M20Doc might have further details. I'd still bet it's something within the cluster since you had issues with multiple gauges. It's possible there is a regulated voltage reference or something inside, but it's hard to tell since Mooney doesn't show any details of the internals. But if you take it apart and something blew enough to make a stink it will probably have left evidence behind. Skip

Two installed and operable batteries are required per the limitations section of the AFM shown above for any of the kinds of operation specified. Per FAR 23.2620, the limitations section is the only section of the AFM requiring FAA approval. Note that there is a change bar for the battery entry, so this limitation may be different in some AFMs. The Limitations in the AFM of current revision for your aircraft is legally binding. Skip

When multiple gauges act up, look for something they all have in common. Pressure gauges read zero when the sender wire is grounded; temperature gauges read full scale when the sender wire is grounded. So, I’d look for some place where multiple wires could be shorted to ground at the same time. I’d start inside the cluster gauge unit since it’s easy to get at. The heat from the cabin heater is not hot enough to damage the teflon-insulated wiring. If the heater hasn’t been used for a long time, I have had a smell come from it for a short time when first turned on - probably just dust in the ducts heating up. But it should dissipate quickly. It’s always a good idea to check the engine compartment for any signs of trouble whenever anything goes amiss with any sender located there - flammable fluids and hot gasses abound there. Skip

From the BOOST website: Pocket Size Boost Oxygen canisters contain over 2 liters of Aviator’s Breathing Oxygen. This equates to approximately 40 seconds of continuous oxygen flow. People report enjoying anywhere between 15-40 inhalations of varying length. Medium Boost Oxygen canisters contain 5 liters of Aviator’s Breathing Oxygen, which is up to 100 one-second inhalations. Large Boost Oxygen canisters contain 10 liters of Aviator’s Breathing Oxygen, which equates to over 200 seconds of continuous oxygen flow, or over 200 one-second inhalations. From www.aqua-calc.com, a liter of oxygen weighs 0.05 ounces. Skip

You might try looking through the 337s and logbooks to see what equipment has been removed to get a clue. My ‘94 J has a light (it’s amber on mine) in the same location labeled GPS ACTIVE. I think it was part of the original factory KLN 90 installation which was removed and replaced with a GNS 430W at the same time the Aspen PFD was added by the previous owner. Since the Aspen annunciates the nav source, any requirement for a separate indicator is eliminated Skip

Does anyone actually use a compass anymore? Years ago, my HSI gyro failed on a MVFR flight in the LA area. I had to fly from Van Nuys to Chino on the compass with 3 sm viz. surrounded by busy airspace. Not that hard, but it did make me wish fo a vertical card compass which I now have. I took the plane to a compass rose and checked both the Aspen and the compass and they were within 2-3 degrees of each other on all 12 points, but in the air I sometimes see 5-6 degrees difference between the two. IIRC Douglas apparently thought so little of the requirement for a magnetic compass on the DC-9 that they installed it behind the right pilot seat and it could only be viewed through a mirror on the glareshield. Skip