EricJ

Ground is ground, and there should only be very small, stray currents going through the shields, so the wire doesn't need to be large. Any current in the shields should be going to the ground rather than through the pin into the connector, too. The 18awg wire indicated from pin 15 to ground is mostly to carry the return current out of the nav/com, particularly during transmit. The note referenced on the drawing may have some additional suggestions.

That line is indicating that all of those shields are grounded at Pin 15. Electrically just grounding one end of a shield (usually at the receiver if it is unidirectional) is better, but in aviation it is common to see shields grounded on both ends. I think this is just for mechanical redundancy in case one end becomes disconnected, but who knows.

No, it doesn't mean that. Airframe approval is separate from engine approval. This is why the limitations in the aircraft POH and specs in the aircraft TCDS drive rather than what's in the engine TCDS.

They do, but just like in cars they can get unregistered and spin. Letting pressure off the bearings during cylinder removal seems to increase the likelihood of this, so it is recognized procedure to not let the case relax too much. Cars also have the benefit of main bearing caps and much more rigid blocks than we have. We have two essentially relatively floppy aluminum case halves to keep the bearings in place.

Appendix D is the minimum regulatory requirement. There is also a regulation that an inspector must use a checklist, and Appendix D is the minimum checklist. Other checklists can be used, like the factory checklist, but they must contain all of the items in Appendix D. I came to the same conclusion, especially after repeatedly repacking bearings that were still full of good grease. There's a tradeoff between doing useful maintenance and increasing the risk of maintenance-induced failures, and doing stuff too often is not productive and adds risk. Agreed. The Lycoming service document on cleaning injectors warns that excessive cleaning of the injectors is detrimental.

There is no requirement to remove wheels or repack bearings for an annual or 100-hour inspection. FAR 43 Appendix D describes the scope and detail of 100-hour and annual inspections. Item (e)(7) in the landing gear section says: (e) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the landing gear group: ... (7) Wheels—for cracks, defects, and condition of bearings. Many inspection items are done blind, like inspecting the condition of rings and valve seats via a compression test, or the condition of seals or gaskets by leak checks, etc. Likewise "condition of bearings" can be tested without removing the wheels, and wheel crack inspections may be done visually, with mirrors or borescopes for parts that are otherwise difficult to see, etc. All of this is done to the satisfaction of the IA, and some may feel that it is necessary to remove the wheels to be comfortable with assessing the conditions of the components, and I think some do it just to assure that the bearings get adequately lubed as that is an oft-neglected component sometimes. The bottom line is that there is no requirement in FAR 43 Appendix D to service anything, except that it is required to "thoroughly clean the aircraft and engine" in Section (a), the very first item in the list. Everything else is just inspection. There may be components, like propellers, that require or suggest annual maintenance in their ICA, and most folks let those coincide with the annual inspection, although it is not required to do so, and ICAs aren't mandatory for Part 91, anyway. Some ADs might have annual requirements, or requirements that are just dealt with at annual for efficiency. I think annual inspections tend to grow in scope because many use it as an opportunity to catch up on deferred maintenance, i.e., they just leave stuff unaddressed to be handled at annual. An airplane with no deferred maintenance would be expected to have an easier time at annual, but even so, if the deferred items aren't airworthiness concerns or covered in Appendix D, they don't really even need to be addressed at annual inspection. It is in a shop's interest to point out as many things as they think they can get hired to fix, so often that's what they do.

Or the lawyers getting paid to send the letters? Yes, it's a convenient way around the bravo, so I think they were sending a lot of these letters out. This was about six years ago, and I haven't heard of anyone getting one of these letters for a long time. That was kind of still early days for mandatory ADS-B-out, too, but I don't know how else they would have been getting tail numbers to look up registrations.

A number of Mites were built as experimentals from drawings, so those drawings existed somewhere. In experimental category there shouldn't be any barrier to converting the wings to metal, or however much of the airplane you want to convert. The FAA would have to be convinced it is safe in order to get an airworthiness certificate in experimental category, but that should be doable.

Significantly west of the river. I dug out the letter, and the description is: 1/2 mile East of Pima to 144th St North/South between Stagecoach Pass and Happy Valley Road. That includes the preserve area around Granite Mountain and Brown's Mountain, but also coincidentally includes Troon (a fairly wealthy neighborhood in North Scottsdale). The request in the letter is to maintain 2000 ft AGL, which is generally not unreasonable. Still, I'm sure they were using the ADS-B-out tail number and registration info to get the addy's to send the letters to.

I noticed that a while back, too, so it's not super-new. Seems to have been done sort of quietly. A few years ago somebody a bit north of where I live would hire a lawyer to send a "strongly worded letter" to anyone who flew below a certain altitude over a particular open area to discourage aircraft from disturbing the wildlife there. It was along a route that is handy to use to avoid the Phoenix bravo airspace and some of the high-density traffic areas sometimes, so I cruised through there once and got one of those letters. Enough people were getting them that the AZ Pilot's Association looked into it enough to include a bit in their newsletter that they're just lawyer letters and could be ignored, but please be considerate about altitudes when you overfly things.

Somewhere I still have my 8" floppy disks with my PDP-11 assembly language assignments on them.

We don't get a lot of IFR around here, so when I'm feeling like I need to fly just for proficiency I'll often go shoot an approach somewhere in VMC, no hood, just flying the approach and doing the buttons and all the equipment setup and manipulation. My autopilot has been inop for many years, so I hand fly all of these. It's not IMC, but it keeps you proficient with anticipating events and flying the airplane according to the approach procedure. I do the usual proficiency flight every six months with a safety pilot, and no autopilot, and that winds up being pretty straightforward if I keep up with doing practice approaches regularly. All that said, I'm not a fan of actual IFR without an autopilot. There's too much multitasking required for me, especially if you get a reroute mid-flight in IMC or something. Fortunately around here it's not been a problem since it's rarely an issue to not be able to get where you need to go VFR.

If it is ever demonstrated in a group that that can be done continually and successfully without creating and tension and division it is an exception to the norm. Even in the barbershop politics and religion are discouraged as conversation topics for generations because the lessons are repeatedly learned. I'd discourage religious conversation here as well, but that doesn't seem to be a problem at the moment. I do like that this thread has been pretty civil, but I wouldn't tempt the beast.

Most states in the US are still very purple overall. The swings are driven mostly by the edge cases in the statistics, which blow back and forth based on events contemporary to particular elections. It is the same everywhere. What you think a particular place is like is often driven by media consumption rather than reality.

I had a similar experience when I bought my airplane. It had sat outside in a big storm before it was delivered here, and we were still sumping water while doing an initial inspection. The airplane went from here to Maxwell's for a tank repair and more inspection. We did some check flights at Maxwell's, during which time I was still draining small amounts of fuel unti clear before flying. Just before returning to AZ the FBO had spilled some fuel and decided to hose the wings down to clean it up. That resulted in a bunch more water in the tanks. I just sampled fuel until no water was evident in the samples, but that kept happening for several flights after that, i.e., water would show up, drain until clear, etc. It took a fair amount of time until I stopped getting water during preflight, but once it was gone, it was gone. I changed out the cap o-rings and haven't had any issues since, but it hasn't really been outside in much rain, either. Shaking the wing likely helps, but if you do see water it's worth keeping an eye on it for a while after that.

Most likely just deposits. Like most things with cylinders, I'd just run it a while and check it again later.

There are a number of failure modes evident in the video. As originally reported, the control handle can be jammed by the o-ring fragments which could prevent selection of a tank or crossfeed, and also prevent being able to shut the fuel off to an engine fire. The o-ring fragments were shown to be able to flow out from the selector to the engine, which can certainly cause issues. Also, since the o-ring disintegration or displacement from their grooves essentially removes them from the system, there could be some uncontrolled flow between all of the ports on the selector, in other words, you lose complete control over the fuel flow. It should not cause an external leak unless the main o-ring to the control shaft failed, which didn't fail in the examples, presumably because it is always in a constrained configuration, unlike the smaller o-rings in the system. It's a dangerous situation, IMHO. It's also not an isolated case, as nitrile/buna-N/etc. rings are still widely used in general aviation.

Yes, after a one-day soak in G100UL in the fuel selector assembly the brand-new o-rings failed after only a few actuations. If there was testing done at GAMI, it either didn't cover a common application like this or the results were not shared or included in their analysis. Neither case is a good situation.

It's easy to not have issues when you're your own DER.

When my airplane has been down at various times I used the opportunity to do something I wouldn't do otherwise, like a tailwheel endorsement, multi-engine rating, etc. Those helped me stay current/proficient/whatever, so I at least didn't feel nearly as rusty when my airplane was available to fly again.

AvareX is a fairly full-featured EFB, and if the user interface and display methodology works for you then it's a good option. It's free, charts and plates are free and geo-referenced, etc., etc. I just got tired of the UI really quickly, but that's just me.

Don't forget to put the Origin and Assembler directives for the assembler at the top of the file. Good practice is to put them together at the top: .ORG .ASM I knew I was going to enjoy my career when I kept running into stuff like that.

AvareX is a complete start-over rewrite of Avare, with an entirely new user interface, display, etc. Not much from Avare carries over to AvareX. They've already stopped update support of Avare, so what you have now is all it's ever going to be, which is fine. I liked it. I suspect, however, that eventually they'll stop supporting chart updates for it.

The AvareX developer seems to be enamored with a particular modern, minimalist "intuitive" interface style, but he doesn't seem to get that it's not intuitive to many people. There is no manual, that's part of the whole deal. It's supposed to be so intuitive that it doesn't need a manual. Everything really is there if you can figure it out, but I didn't want to be flying along trying to figure out for the nth time how to do something, so I switched to iFly, which I do find 100x easier to use. FWIW, the old Avare was really nice. I don't know why they thought they had to change the entire UI or how they display everything in the new version. Some of the old display features were really useful and just don't exist in AvareX. It's still a fully functional, useful EFB if you grok the UI, I just found it too frustrating to use. That's a shame as I really liked the old version.

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).