Really funny to read about my backup alternator installation 
Yes that is the guy who did the field approval for me. I posted about him here too, hoping he would get some work from it – here.
Of course solid state stuff should be more reliable. But look at the cost. And you can’t really keep a spare 10k item. I have a spare KLN94…
To illustrate the opportunistic benefits, I bought two KC225 computers for 500 bucks each! 8130 form of course, overhauled by Honeywell. New about 10k each. Had a bit of fun with one of them though – described here because it had a duff display. This is a lesson that when you buy spares you need to test them ASAP.
The other issue with buying spares which come with some warranty is that the warranty will expire while they are on the shelf, and I know from experience that if you find it is faulty, no amount of pressure will make the vendor do anything other than wash their hands of it!
Malibuflyer – I have a fleet of one ;) but subscribe to Peter’s approach of picking stuff up as it becomes available for cheap, not paying whatever the market wants the instant something broke and I need it NOW. And, to be honest, I hope it will be a case of “since he has a spare, no point in breaking down, might as well not break”. I would seriously consider your “hot spare” approach, but that is not feasible in my Mooney, the panel is just too small. I do have an electric AI in the panel, so “almost there” and different power source for improved resilience, but it won’t drive the AP.
Zuutroy – in principle I agree with you, but I want to replace things at my own pace, not by being forced into replacing them. Say KI256 – I can replace it with a GI275 for say $10k installed, if I’m lucky, or use the spare I bought for $500 and hold out till Dynon gets the HDX autopilot certified for M20’s. Yes, it means I’ll end up with lots of useless devices on a shelf, but for me that’s the cost of playing the game. And no, I cannot use the G5, because it won’t drive the KFC200 autopilot. Also, with older planes that have a single battery / alternator, it kind of becomes an “all eggs in one basket” kind of thing, and following a recent discussion started by jlunseth over on MooneySpace and I think his logic has some validity. The 337 route for getting a standby alternator installed, also discussed on MS here and here – and with what I think is a reference to Peter’s installation in the 1st link.
I’ll allow myself to disagree with Peter and say that I think that a proper solid state setup will be more resilient overall, and much more maintainable; but the long term goal would be to replace “everything” with modern-ish devices – not just the AI, but also the HSI and the autopilot.
To add insult to injury, my AP started throwing a fit and pitching down…
With apologies to Clint Eastwood, there are two kinds of pilots:
But seriously I don’t think the new stuff is more reliable than the old stuff – with some specific exceptions. What does happen is that when something new packs up, you lose a lot more functionality all in one go.
To get really high uptime with the separates, you need to keep spares, or be based near a shop with lots of spares and never fly too far.
To get really high uptime with the integrated avionics, you need to be based near a dealer and never fly too far.
Electronics should be more reliable than mechanicals, obviously, and I’ve been doing electronics since the early 1970s so I know how it works. But there are things which kill electronics too: vibration (coupled with poor mech design), thermal cycling, corrosion…
If I went full-glass I would absolutely want all the dealer access codes/keys. We’ve done this before; it is possible with some and not others. I know a dealer in the US who says he would sell me anything and all the access codes, but then I have no useful warranty. OTOH there are avionics companies which have no European presence e.g. Avidyne…
In most cases, replacing a mech item with an electronic one is a huge job. Even the most obvious ones e.g. replacing a KI256 have poor options. We have discussed the KI256 I doubt an Aspen+EA100 (much has been written on that one) will be more reliable than a KI256 + the vac pump.
Keeping spares is a cheap strategy, and they get cheaper all the time as more people rip them out and throw them on US Ebay.
I suppose if you can get something you can legally fit for a good price, then maybe. For all of the stuff in the title you’d be looking at 500-1k for a replacement vs 2-3k for a G5 or GI275 with more functionality and the potential to get rid of the vacuum system entirely. My HSI went and I got a single G5. When the AI goes I’ll get a 275 or maybe go Aspen, and if the KFC150 box goes then I’ll go for a GFC500 though that is certainly more painful, financially.
zuutroy wrote:
Would it not be a better approach (for the mentioned avionics) to just pony up and replace these items with non-fossils when they break?
Not for all of them there is an affordable like for like replacement.
And you might not want to do a 10-100k avionics overhaul just because a part you can shot at Ebay for 500 USD when you are lucky and have no time pressure fails…
Would it not be a better approach (for the mentioned avionics) to just pony up and replace these items with non-fossils when they break?
Keeping spares makes a dramatic difference to downtime / AOG issues.
It also makes it possible to do quick troubleshooting, by swapping stuff.
It also means regular component overhauls (mags etc) have zero downtime.
Otherwise, to get replacement items, you need to have a very good “relationship” with a shop which is willing to lend you stuff. That sort of thing does exist but in every case I have known it was done with a shop
Most aircraft owners are in some sort of “middle ground” where they don’t have access to some handy facility like that.
It works best with an N-reg and a friendly freelance A&P who can sign off the swap in the logbook. I am not sure if any EASA66 guy is similarly authorised; isn’t there a “radio license” of some sort?
Another advantage is that you can buy up these spares at time and place of your choosing, on US Ebay for example, and not when you are stuck somewhere and over a barrel. Recently a kind ex owner gave me a Shadin fuel totaliser (the panel instrument). This is worth at least 1k. I may not need it for years, but…
Agree – it is really the question of what you are solving for:
If it’s really about “having a cold standby” that you could screw into the panel within minutes to avoid aircraft on the ground, I fully agree that your solution is a (perhaps the only) feasible one. In those cases, however, I assume that your fleet is so big that we are more talking about storing them a year rather than 10 years before use.
If it is more for “having a spare one because you never know if when mine is failing in 8 years I will find one on the used market at a reasonable price” then some days for the shop might not hurt too much.
And by the way the second use case does make lot’s of sense: The prices for such used equipement differ by orders of magnitude whether you “need to buy one now because yours failed” or you “happen to find one from someone that just updated his avionics”
I do see value in your approach, Malibuflyer, but it kind of defeats the purpose of having a spare ready for installation if I need it to go to a shop before I can use it. I’m looking into picking up a whole electric standby vacuum system on the cheap to make sure the cure I apply is not worse than the disease; I already have a vacuum pump and filter that silently became trash in the CAMO’s eyes.
I would consider not trying to “keep them moving” during storage (at the risk of damaging something by messing with pressure or not using the adequate dust filters) but rather keep them packed and dry and investing the money for the “movement rig” into an avionics shop doing a “cleaning and greasing” service before installation.
