Vance Harral

That streamlined design was installed on the last of the F models, including our 1976 M20F. That's likely sufficient "approved data" for any mechanic to be comfortable installing it on any F model.

Let's all remember that everyone has a finite budget. Some more than others, obviously, but the question here is not really whether a 2nd nav/comm would increase safety. Rather, it's whether the small risk reduction in doing so is the best use of safety dollars for this owner and his mission, given an already pretty-well-equipped airplane. The guy already said his mission is limited to "gentleman's IFR", which isn't significantly higher risk in the what-if department vs. a VFR-only pilot who might accidentally stumble into IMC. Yes, I suppose his GTN could lock up right as he enters a thin layer, at the same moment that layer quickly turns into widespread IFR for hundreds of miles. Maybe the GTN is actually electrically damaged, such that it doesn't respond to power cycling. But what is the risk of that compared with all the other risks he assumes? Engine failure? Loss of control? To put some numbers on it, looks like a used KX-155 is running $1500-$2000 on eBay, and let's hazard a guess it would be another $1000 to install. $2500-$3000 walk-away price for the increased safety of a 2nd nav/com. But I'd wager $1000 spent by the OP on 10-ish hours of training with a good CFII on equipment failures (including simulated failure of his only NAV/COM), as well as takeoffs and landings and unusual attitude recoveries, would reduce his risk a lot more than the additional equipment, for thousands of dollars less. That's a good tradeoff.

@Hank probably knows this, but just for others reading the thread... some carbureted aircraft don't have a primer systems that inject fuel directly into the cylinders. Including some Mooneys, and I'm guessing Hank's is one of them. Pumping the throttle to force the accelerator pump to spray atomized fuel up into the carburetor throat is the only way to prime the engine in these airplanes. But please be careful about dispensing "pump the throttle to prime" advice, even in carbureted aircraft. Most carbureted airplanes have updraft carbs (fuel/air path into the engine intake is opposite gravity), and some of them don't atomize the fuel all that well, especially when it's cold. In these aircraft, some of the fuel you shoot into the carburetor throat by pumping the throttle runs back down over the carburetor, into the engine cowl, onto the ground, etc. This is a fire hazard, and not just a theoretical one - a 182 at our flight school suffered significant damage in a carburetor fire caused by someone who wasn't very skilled getting the engine started, and managed to light off an engine compartment fire after excessive throttle pumping. It's definitely safer to use a primer vs. pumping the throttle, though the risk reduction is hard to quantify. If you must pump the throttle to get the engine started, one way to mitigate risk is to only pump the throttle while actually cranking the starter. With this method, the vacuum generated in the intake by the moving cylinders will draw more of the fuel droplets up into the engine, less of them will rain down on the ground. I'm aware this isn't the POH procedure, but it has been effective for me in a number of carbureted airplanes, and I think it's safer. The "hot start problem" in fuel injected engines is almost entirely caused by the the fuel injector lines being routed right over the cylinder heads, such that the fuel in them is baked and vaporized by the hot cylinders as soon as cooling air stops flowing over them, i.e. immediately after shutdown. Lycoming/Continental carbureted engines don't have this problem because the entire fuel/air intake system is below the hot cylinder heads, so there's really no comparison between carbuerted/fuel-injected with regard to hot starts. Indeed, carbureted engines are almost always blissfully easy to start when warm. For what it's worth, your engine would likely start with zero throttle pumps when warm, albeit after a few more blades than with pumping. Reduces the admittedly small risk of a carburetor fire, at the expense of more wear on your starter.

I wouldn't teach IFR in widespread low IMC in an aircraft with only one GTN-650 for navigation. My concerns would be a combination of lack of redundancy, and the additional distraction of using a single flip-flop to juggle three COM frequencies during the transition from initial to final approach (weather, ARTCC/TRACON, Tower/CTAF). Those concerns aren't show stoppers, but it would really detract from my enjoyment. That said, lot of people with instrument ratings only fly "gentleman's IFR", i.e. mostly VMC with an occasional climb/descent through a thin layer well above the ground. I'd fly with the OP in their airplane under those circumstances.

The "takes a few seconds to settle down" occurs in our IO-360-powered M20F as well. It's been doing that for literally two decades, and I've come to think of it as normal. But it still bugs me because it would make it difficult to distinguish actual morning sickness (stuck valve) from whatever is otherwise happening. That said, you're wise to note that this is a new behavior. Something has changed. It might be a change in the starting mixture based on a change in air density relative to your constant 5 seconds of prime. But I'm always a little skeptical about this stuff. Pilots tend to claim there are known good formulas for priming, e.g. "5 seconds when cold, 3 seconds when warm" or whatever. But I think the actual fuel/air mixture you get in the cylinders at engine start is a result of multiple complex inputs (not just air temperature, but also fuel servo temperature, throttle position, rate at which you move the mixture lever, and so on); and that an engine that starts easily mostly does so through the grace of there being a broad variety of fuel/air mixtures that are combustible.

Well, as with any large, bureaucratic organization, it's hit or miss. My OSA SI, and a friend's SI for a stent, were relatively painless. Good experience with the AME that handled the process, reasonably prompt response from CAMI, requirements well-documented and evidence thereof accepted without further question. SI in-hand after a few weeks for me and a few months for my friend. There's no doubt others have bad experiences, and I'm sure one's likelihood of a good/bad experience varies from year to year as staff, administrators, and the executive branch change. But I also think it's important to give counterpoints to the sort of guaranteed-gloom-and-doom outlook other folks make here, because that sort of panic is exactly what leads people to conclude they have to sell their airplane and give up flying, when it's not actually the case. No quarrel from me about moving to BasicMed (or MOSAIC Sport pilot now) once a standard medical is obtained. But a subset of us want to preserve the legal right to offer paid ferry services, fly turbo Mooneys above 18,000, and so on.

First need to clarify if the OP simply has obstructive sleep apnea, or actual anemia interrelated with some sort of sleep problem. If it's "only" OSA, the special-issuance medical has become very common and arguably trivial compared with other denials (I speak from experience, I've been carrying a 2nd class SI medical with OSA for years). Make an appointment with a sleep clinic. Meet the doc and pick up the at-home-sleep-test-equipment (make sure it's "Type II", see https://www.faa.gov/ame_guide/media/OSA_FAQs.pdf). Wear the test equipment one night, send results to the clinic. For better or worse, you're essentially guaranteed to receive a diagnosis for OSA and a recommendation to treat with CPAP therapy. Buy the CPAP equipment and get used to sleeping with it (this is the hardest part, but you can do it). As soon as you and your doc agree you are "tolerating therapy", you can apply for the SI. Downtime on this is measured in weeks, not years, and you can fly with a PIC-current qualified pilot and/or instructor while waiting on the process. There are treatments other than CPAP such as dental devices, but I can't speak to that personally.

Lots of 70s-era M20 models are wired like this anyway. The "feature" of the SOS engaging on key twist before push is not universal, only some vintage Mooneys work this way.

When and if you get around to buying exterior screws, I second this advice. There just aren't that many different types of screws on the exterior of an M20F, and it's not that hard to get the exact part numbers from the IPC. The kits always seem to be a bit off, and even if you had a perfect kit it's not like the kit itself tells you which screws are really supposed to go in which panels.

Because one of the concerns with Vne is flutter, and the onset of flutter is a function of both indicated and true airspeed, not just indicated. A decent article is available at https://www.kitplanes.com/wind-tunnel-36/

That's my experience as well. The heavy flight training activity at some class D airports creates a particular kind of demand that just isn't found at "larger" airports. ATC staffing shortages are making the Class D situation worse, and not just in the obvious way. The nearest Class D to me (KBJC) increasingly refuses pattern work due to "staffing issues", but that doesn't stop the pattern work, of course - it just ships it out to nearby untowered airports. This (1) floods the suburban airports that used to have fairly easygoing patterns with demand they are not really designed to handle; (2) generates a ton of inbound/outbound traffic to KBJC itself which has now spawned local procedures that aren't published in official sources ("Cleared for takeoff, fly to Costco", I kid you not); and (3) generally results in angry flying. To that last point, we have instructors and students from KBJC who resent having to add 30-60 minutes of transition movement to what would ideally be a flight focused on approach and landing work, and furious locals at the nearby airports who sit on the ground waiting for the 5-6 flight school airplanes in the pattern to figure out that someone needs to make a hole for departures. Flying angry is counter to flying safely. I teach out of multiple airports in the area, so I see both sides of this, and don't blame any particular flight school or ATC organization for it. But it's frustrating. I try to be understanding, but every time I tune the ATIS at KBJC and hear, "Pattern work is limited/unavailable due to staffing issues", my brain mentally translates it to, "F**K YOU OTHER NEARBY AIRPORTS - YOU'LL TAKE OUR OVERFLOW AND LIKE IT!" The prankster in me wants to record a message on the AWOS at the nearby airports that says, "Due to staffing issues, pattern work by KBJC flight schools is unavailable. Go back home." The huge demand for flight training is good for "the industry", I guess. But in these days of waning supply of airline jobs, it feels like a pyramid scheme to me. I understand that occasionally the "forthcoming pilot shortage" is real. But I also run across a lot of defeated kids with a fresh CFI, mountains of debt, and no job prospects.

That makes sense, as a waypoint in the source device might not exist in the destination device. With time and knob-ology experience, I've become indifferent about crossfill, and hostile to "autosync" where one device is always slaved to the other, be it between two panel-mount navigators or - more commonly these days - EFB to/from panel mount. For me, it causes more problems than it solves, e.g. lack of ability to use one device for "what if" nav planning while the other is active. But I say that as someone who flies IFR in a part of the world where there is never an urgent need to get more than one or two waypoints into a navigator flightplan at a time. I might feel differently if I flew a lot of routes that involve lots of waypoints over short distances.

Yes, here we go down the rabbit hole. This is well and good, but the Reference Guide is yet another pamphlet-like document that is not the voluminous Pilot's Guide often found in the cockpit. Even the Reference Guide is not required unless "navigation is predicated on the use of the GTN." I think most would agree that flying IFR departure/enroute/approach procedures using guidance from the GTN triggers that clause. I'm less sure about VFR ops and lean toward arguing those do not trigger the clause. Getting a bit off topic here, but an AFMS limitation that comes up in CFII debates from time to time is this one: I've had fellow instructors claim there is nothing in FAA literature which prohibits flying an instrument approach with an expired database provided you "verify each waypoint for accuracy". That may be true, but if you're Garmin equipped it doesn't matter, because the AFMS for Garmin navigators explicitly prohibits it, allowing the "verify each waypoint" trick only for terminal and enroute ops. I don't know if other navigators (e.g. Avidyne) contain this same AFMS limitation.

Can't say, I've never been to H81. I just know that KTDW has treated us well, many times. @midlifeflyer's story about KAMA being quiet makes sense to me, and I wouldn't avoid it because it's "busy", I just think KTDW has cheaper gas, is closer to town, and now has the restaurant. Getting a bit off topic here, but in my experience, Class C towered airports are a lot more pleasant to fly into than Class D towered airports. I think a lot of pilots get introduced to towered airport ops at a busy Class D, and conclude that flying into a Class C must be even crazier, but it's often the opposite. Here in the Denver Metro area, I'd take a flight into KCOS over one to KBJC or KAPA, any day, and any time of day.

Just to be clear, the screenshot you posted is from the Pilot's Guide, not the AFMS. Two different documents with different legal status. There is a lot of understandable confusion about this. The voluminous "Pilot's Guide" may be nice to have with you, but it's not legally required in the airplane, and nothing it contains is regulatory. In contrast, the pamphlet-like Airplane Flight Manual Supplement (AFMS) is required to be in the aircraft, and anything found in its LIMITATIONS section is binding from a regulatory standpoint. The AFMS is not only serial-number specific, it is also software revision specific - you're supposed to get a new one with each software upgrade. I've been invited into several clients' airplanes in which the required AFMS is nowhere to be found. Sometimes the installation shop didn't provide it. But in other cases the owner is just confused - they put the not-required Pilot's Guide in the cockpit while filing away the required AFMS along with their invoice, warranty paperwork, and so forth. Here's a screenshot of the first page of a "generic" GTN650 AFMS, awaiting the make/model/registration/serial number info to be filled in. If you don't have this in your airplane with your Garmin navigator (GNS, GTN, etc.), you're failing the "weight of paperwork must equal weight of airplane" rule.