Not at all, it was an interesting read.
Outside the jet for work, I fly a twin turboprop Peter. For light aircraft the list is too long. I've lost 2 vac pumps (not at the same time) on a C310, one on a Cherokee, several whilst instructing on singles such as the TB10 and that ilk. In the region of 5 pumps over several thousand hours g/a time.
You say you change the (inexpensive) pump every 250 hours.
That's my whole point. Your the one suggesting replacing parts on a pure time basis is in most cases totally pointless.
Replacing bits on a pure time basis is in most cases in fixed wing GA totally pointless.
Contradiction? I take it the two items I mention come under your "mostly" part? You also self admittedly say two vac pumps are not a bad idea...
Replacing bits which are worn is OK.
Well, thanks for the advice. I'll make sure I let our company engineers know that...
What about the Thai aero clubs TB20 with two alternators? They base their regs pretty much on the FAR's. It must be possible.
Seatbelts? Now who's being "disingenuous"...
Oil hoses? Are they not a 10 year lifed item on your '20? if that's what the AMM suggests, then do it. But you have haven't you? I'm sure that's on the website somewhere! Personally if it was my aircraft, I would. That's regardless as to whether under part 91 it's required or not. The JAA seem to think so.
An electric backup vac pump doesn't help with that, because if the AI goes, so does (on Honeywell systems) the autopilot, which is just what you want
Oh no, the autopilot has failed! Declare an emergency!