EricJ

It would have failed a number of annual inspections or other inspections if the actual airworthiness certificate was missing, which is *not* that logbook entry. If there was ever a checkride done in that airplane the DPE would likely have checked that the AWC was there as well. So it is highly unlikely that it has been missing for a long time.

There used to be a lot of institutional biases against "free" or "open source" projects because of perceived quality issues. In many areas that's been swinging the other way, or at least there's no longer a quality assumption either way. The increasing trend to minimize testing or minimize development time or cost (via things like agile) has led to a signficant decline in commercial software quality in many markets for a long time. So now there are many customers that may prefer open source for quite a few reasons. Another aspect is that most open-source projects don't do a lot of marketing or have sales people, so they're expected to be underdogs in the market. The big corporations aren't always their target market, so, yeah, they often don't wind up there. Sometimes they do, though, and that seems to be happening more these days than it used to. I've been genuinely surprised to see some of the places where a complex, highly-integrated app with security needs, etc., etc., turns out to be open-source (e.g., TAK/ATAK).

The math isn't that hard. I've been working on a tracker to locate ELTs with a low-cost portable system. I've been using wx bots (ASOS, AWOS, etc.) as proxies for testing, and made a CDI display (on the tablet) to facilitate tracking to the estimated emitter location lat/lon, which gets continuously improved using various radio signal processing techniques. I had to make my own lat/lon math processing library because I couldn't find one suitable for what I was doing. It's not trivial, but the math isn't all that hard. I did the whole library by myself in not much time. Graphics processing is old hat these days since so many applications need it with a lot of libraries available for that as well. I think the main challenge with EFBs is integrating the various rendering, processing, database, UI functions into something that doesn't continually step on itself and make a non-functional mess. It appears that just having good, modern tools helps this a lot, which seems to be a critical element to the success of the new AvareX, which simultaneously integrates and develops everything from one source for multiple platforms.

Even critical missions with government customers tend to move toward open source these days. The transparency is a significant benefit for security analysis.

That's pretty much what AvareX is (and Avare before it). There are some other open-source EFBs, too, that are similar but seem to be not as popular.

It's possible that the orientation of that link makes no difference.

I used Avare, one of the free EFBs for many years and liked it a lot. The developer decided to stop support and start over using some of the newer development tools that make cross-development possible (to multiple platforms simultaneously). So now we have AvareX, which was developed by a few volunteers relatively quickly and is already reasonably full-featured as EFBs go, and is available on Android, Apple, Microsoft, etc.. I don't like the new user interfaces in AvareX, or the lack of documentation, so I switched to iFly, but I think AvareX is a bit of an example proof that it might not be as hard these days as it once was due to the modern software tool sets. It's definitely not trivial or inexpensive if you wanted to fund a similar effort, but it's apparently not the hurdle it may have been in the past. So there still are free EFBs out that that are very usable, and low-cost subscription alternatives like iFly. Avare, AvareX and iFly and other EFBs all have free charts and plates, so there are no fees related to the charts or plates. They're all still geo-referenced, too. I think one of the pressures on Jeppesen has been that they weren't offering much value-add compared to the free government charts used in many of these other EFBs, so I suspect that's part of why their prices came down. It'll be interesting to see what happens from here. This acquisition is just capitalists doing capitalism. I'm told it makes everything more efficient.

Field approvals happen all the time. Our local FSDO has been encouraging them, and I've heard that from reps from other FSDOs as well. The older G1000s are not well supported as evidenced by the difficulty of adding WAAS. I fly fairly regularly behind various G1000 systems including old stuff and newer NXi stuff, and compared to the newer stuff like the G3X I find the user interface of the G1000 extremely clunky. Some who use both find the GFC500 to be a much better autopilot than the GFC700. I totally understand somebody wanting to upgrade from an older G1000 to a newer system, whatever it might be.

Or a field approval. You can change anything with a field approval. People have changed engines with field approvals. Since L, M, R and S models are listed on the G3X AML the approved data already exists.

The AML includes M20L, M20M, M20R and M20S. The note says "Excluding aircraft equipped with G1000". If you uninstall the G1000, I think it would not be unreasonable to say the AML includes those aircraft. If somebody thinks additional approval is required, the STC data for those aircraft would likely get you close enough that a DER (or not) for a field approval would not be missing much, so I would not expect the expense of developing the data for the aircraft to be excessive. I've recently seen seeing FSDOs (including our local one) encouraging field approvals, so it might be worth trying. I don't see a regulatory barrier here.

There's a scat tube that is supposed to be connected between the muffler shroud and the mixing box on the passenger side firewall. If that hose is loose or disconnected, or the mixing box control not working, you could get what you're describing. Edit: You can see a lot of that just by looking into the oil hatch.

It doesn't look like corrosion, but it's often hard to tell for certain from a pic. A pre-buy inspection with a note pointing to check that specifically would be a good idea.

Sound like you did all the right things. Had you been cruising with the ram air open by any chance? Was there any moisture in the air where you were cruising? The fuel servo is sensitive to what happens with the ram tubes, and if the ram air is open and there's any moisture in the air I'm guessing it's possible either one or more ram tubes iced over or moisture was ingested into a ram tube and froze inside the servo. There's all kinds of crazy stuff can happen when then servo isn't happy, including failing (I've been there, too). It would also explain why everything was fine afterward. That's just speculation on my part, but it might have been something crazy like that. Edit: BTW, nicely done and I'm glad it came out well and you're getting it sorted out.

That'd be my thought. Likewise a DER, if needed, shouldn't have too much trouble working from the usual installation manual. There's always a way to do it, and I suspect the DER/approval wouldn't be a huge expense compared to the avionics and installation.

FWIW, Garmin still makes the G1000, and it is still being delivered in new airplanes. I don't know what the compatibility issues may or may not be with older G1000s and new replacement parts, because there is definitely an evolution there, but Garmin or a Garmin dealer should be useful there. In other words, if a component of an older G1000 needs to be replaced or updated, that may still be possible. If I were considering purchasing an aircraft with an older G1000, I'd look at that. We recently replaced a G1000 MFD in a 2015 C182 that I help with occasionally and the shop that did it just ordered the part and replaced it. Not cheap, but definitely doable. I don't know how much worse it might or might not be for a 2005.

It seems a dilemna whether to reseal before or after paint. The reseal strip might damage the paint, and the paint strip might damage the reseal.

+1 that that looks more like a prep issue. An existing leak or two weren't cleaned up during the process.

I think that's another risky part of it. Just like moving the prop control forward too fast, moving the throttle forward too fast may lead to an overspeed, which is very hard on things like valve springs, etc.

I'm trying to figure out whether the gear collapsed or stuff just got a bit tore up because it slid backwards a bit. It's probably all fixable, regardless.

Less paint staining than G100UL!

The IO-550 in the M20S is a Continental engine, so unaffected by the Lycoming SB. Most of the engines on the affected model list in that SB are geared, which creates a number of similar operating concerns, including making sure the engine is always producing positive thrust, so there are some additional factors at work there. The Lycoming IO-360s in the J model Mooneys also have dynamic counter weights and aren't on the affected model list and don't really have this concern. I don't think the TIO-540 in the M model does, either. I'm not aware of any similar concerns for the Continental engines. Just fwiw.

I don't think I've ever seen one unpainted, either, fwiw.

On-board weather helps, too. I try to stay away from purple stuff, at least. We don't get a lot of experience with that stuff here in the southwest, though, so it's not very often that it's even been an issue for me.

Basically, yes and no. No from the standpoint that you can't put anything "non blessed" on a certificated airplane, but Yes in the sense that there has been a lot of interpretation and guidance on what "blessed" means, particularly for "vintage" or orphaned aircraft. AC 23-27 is one example of guidance specifically provided for these cases. Additionally, there is a fair amount of room for creativity in Owner Produced Parts, and the ability to put a stake in it so that nobody makes you take it back off via the VARMA process, which is also specifically for "vintage" aircraft (it's the V in VARMA). These are all FAA efforts to make it more practical to maintain aging or "vintage" or orphaned airplanes with little or no factory support. All of this applies to part substitution, but can often be interpreted to apply to repair or overhaul, since the overhauled or repaired part could be considered a substitute for an original. Your IA is the guy who's opinion matters on all this, since he's the one that signs the logbook. VARMA is a path to verify that something that might seem sketchy may actually be approved, so that an IA with a different opinion doesn't make you take it back off later. Coordination and cooperation with your IA is key, since they can even "supervise" you doing the work and then sign it off if they're satisfied that things were done correctly according to the regs and various guidances. Some IAs are much more flexible on this than others, since some of it does require interpretation or understanding of the various regs and advice. We've been a bit surprised sometimes on how pragmatic the FAA reps can be on this during public presentations, so it really does need to be done carefully in consultation with the people you work with (i.e., your IA). So, imho, you can get there from here, but it isn't always easy, and it takes being careful about navigating the regs and guidance in a way that is supportable for whatever you're trying to do. My personal standard is that if I'm okay with standing in front of a judge explaining why I did something, then that's a reasonable path.

An acquaintance I used to race with bought a UH-1H out of a museum and flew it around for a while. He was not a very responsible-type of person and flew it in what was evidently a bad configuration in ways it should not have been flown, and he was told as much by more than one person. Repeated mast bumping ultimately caused rotor separation and when the rotor came of it sliced the crap out of the airframe, including chopping the tail off as well as neatly slicing off the entire right side of the helicopter which separated with the main door still in its tracks. If you want to go down a rabbit hole of learning how not to do things with a Huey, you can follow the links through the NTSB report to the supporting documents, etc. https://asn.flightsafety.org/wikibase/wiki.php?id=160816