What Autopilot for PA28 Arrow III when upgrading

Snoopy wrote:

That ship has sailed. It’s GFC500 or nothing.

Monopolies are never of anybodies advantage.

With the same conviction I could claim “For any one who has an Aspen, Garmin is no-go.”

Or: “If you want an AP, buy an airplane which has one.” That actually is probably the most sensible one. ANY installation today is quite often more expensive than the actual airplane.

With our fleet of airplanes which has all sorts of different equipment, tunnel vision costs a lot of money.

Mooney_Driver wrote:

Monopolies are never of anybodies advantage.

You are right – it is not. Although, could it be legally confirmed if it is a monopoly?
Because if it can, then surely it must regulated by law in pretty much any country, and in the EU/UK it means the regulators are likely to be able to dictate prices and read internal e-mails. :)

arj1 wrote:

Although, could it be legally confirmed if it is a monopoly?

As the others are just dragging their feet probably not. Which does not change the fact that there is very little choice.

Peter wrote:

Actually so does any autopilot, 1980s or later, that isn’t shagged

I believe that to be true, albeit I don’t have the big picture. We’re not comparing apples with apples on the one side a new installation setup of a GFC500 and on the other side worn out installations. I’ll be interested in seeing the outcome in all the Garmin installations in 50 or 60 years.

My A/P had been resurrected about 10 years ago and is now, in combination with the Aspen PFD and the GPS Steering commands from a GTN650 really flying “on rails”. Having it flying an approach or any other use case is just a computer game. Looks like the A/P was in good hands for that.

Just out of curiosity and as I had a really interesting offer for all parts of an 55x (most parts new) I asked around what costs might be involved for releasing such an installation. Turned out to be a no-go. STEC said that the parts could not be used (which I don’t believe to be true because it was designed for same model and type) and turning around and around buying new was cheaper than using this set of parts. Thank you, no.

arj1 wrote:

Although, could it be legally confirmed if it is a monopoly?

It is not a monopoly. It is a lack of competitors in a market that is too small to have any real-world impact. It is a market that has very high access limitations, that only starts with certification and STCs. Non-certified installations are way ahead in terms of functionality.

Every now and then a competitor device turns up, where the most interesting ones are bought away on the step of getting certified. Wasn’t that the case with the TruTrack Autopilot recently? That’s now rebranded King if I’m not mistaken.

Any other than that: the GFC500 is a huge step in “bangs for bucks” for all of us. In comparison to the market situation before, it is about to make autopilots a lot cheaper. So as always the medal does have two sides.

STEC’s attitude smells really bad but their position is to the advantage of “the industry” – revenue maximisation.

Garmin can do what they like – this sector is too small for anyone to go after them for anticompetitive practices.

Trutrak and Trio cannot fly ILS, or actually any “NAV” source AFAIK. Here.

GFC500 has an interesting problem which may worry you, or not… Personally I would not have it because an ILS is the lifesaver when other options are lost.

Peter wrote:

GFC500 has an interesting problem which may worry you, or not… Personally I would not have it because an ILS is the lifesaver when other options are lost.

yes, that is what was mentioned earlier why the 55x and that generation APs have an advantage there. You can loose a lot of stuff and still got a working AP. And you can fly an ILS based on any coupled NAV receiver.

I recall vividly when I got my difference training on a lovely Seneca I many many years ago which had a Piper Altimatic IIIb Autopilot.

This was before GPS so it was coupled to a venable KY175B ILS receiver and a HSI.

The owners were a flight school, whose instructors did not like the airplane. I loved it because it was massively cheaper to rent than the Seneca II. During difference training I was told to leave that p.o.s alone for anyhing but HDG/ALT hold. Well, I did a bit of rtfm and started trying the different functions and found it worked perfectly, including altitude preselect and ILS coupling, no difference really to the KFC 150 I knew but for the lack of FD. It was a bit fiddly to work with until you got the hang out of it. But it was in no way inferior to an STEC, but rather better in holding localizers and VOR radials. I bet it would do fine doing GPSS using an Aspen too.

When i was window shopping for a Twin Comanche i would always look for exemplars with that AP. I would much prefer it to any Stec 30 or 50. However, a 55x with autotrim and internal GPSS of course has it’s advantages over this one.

Really old stuff like the above is almost impossible to repair today. Not because it can’t be done (the schematics have escaped into the wild long ago) but because there are few options for doing it legally.

Anyway the OP wrote

What autopilot would you suggest when it’s time to change the old Auto control IIIb 1-axis auto pilot?

which suggests it is still working.

This is what that looks like

There are lots of options for replacing parts from Ebay, off the books Lots of people are doing it, hence the sales on Ebay.

It looks like it has a heading hold but not altitude hold; you trim manually. IOW, a “wing leveller” with heading mode.

Anything big will be 5 digits.

GFC500 has an interesting problem which may worry you, or not… Personally I would not have it because an ILS is the lifesaver when other options are lost.

Very hypothetical but I believe accepting a crappy rate based AP 99.9% of the time because it also works without GPS in a 0.01% chance is a much higher risk than having a modern digital ESP/USP featuring AP for 99.9% of the time and accepting that 0.01% case where loss of GPS requires manually flown approach.