Spend my money - which autopilot?

traumamed

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traumamed
I have a Piper Turbo Arrow III (PA-28R-201T) that needs an autopilot. The current panel is an Aspen Pro Max PFD, G5 backup AI, GTN 750, GTX 345, an old King backup NAV2, an actual working King DME, and a JPI 900.

The current autopilot situation is clunky and now broken. It has an STEC 30 standalone alt hold for vertical, which still works fine. The ailerons are driven by an Autocontrol IIIB (basically a rebranded Century IIB) which is connected to the Aspen for GPSS. It recently became intermittent and unreliable. I have traced the problem to the connector at the back of the head unit. I've been in touch with Autopilots Central in OK, and unfortunately this is a much bigger issue than it would seem because the connector itself is no longer available. The repair could involve building a whole new wiring harness. I don't want to spend that kind of coin on an ancient analog AP.

I've come up with a few options for replacing the AP entirely.

1. GFC500 driven by my G5. Great AP, but in this config, it would basically relegate my Aspen to a monitoring screen. I would actually be flying the G5.

2. GFC500 + swap out the Aspen for a TXi. This would be the dream for achieving a fully integrated panel. Idk if I can swing the cost though.

3. GFC500 + swap out the Aspen for two GI-275s. I'd have an integrated panel, but I feel like trading out an Aspen Pro Max for GI-275s would be a backwards move.

4. STEC 55x. Idk much about this AP except that a bunch of people upgraded from it to a 3100. Unfortunately, there is not an STC for the 3100 in my plane. If I went 55x, I think the pitch servo from my STEC 30 can be reused, so that would probably reduce the price of this option. I do know the 55x can integrate well with both the Aspen and the GTN.

What would the PoA collective do?

PS - I'm sure someone will mention the Aerocruze 100 and the Trio, but those do not work for my situation. I fly IFR a lot. The lack of approval for instrument approaches and the inability to follow ground-based nav aids are dealbreakers.
 
Get the GFC500 with the G5’s or GI275’s. Either will be amazing!
 
And why not consider G3X/GFC500 combo, you already have the G5?
 
And why not consider G3X/GFC500 combo, you already have the G5?
I'm not opposed to it. I just didn't think the price difference would be significant enough to merit considering the G3X over the newer piece of tech. The bulk of the cost is going to be the installation, which will require panel modification or might even mean cutting a new panel entirely. If I go all in on a project that could approach mid-five figures, a couple thousand more for the G500TXi seems trivial. I'm all ears if I'm missing something. I would much rather keep a unified, large-screen PFD than go back to two little steam-gauge-sized circles just to get the AP well integrated.
 
I'm not opposed to it. I just didn't think the price difference would be significant enough to merit considering the G3X over the newer piece of tech. The bulk of the cost is going to be the installation, which will require panel modification or might even mean cutting a new panel entirely. If I go all in on a project that could approach mid-five figures, a couple thousand more for the G500TXi seems trivial. I'm all ears if I'm missing something. I would much rather keep a unified, large-screen PFD than go back to two little steam-gauge-sized circles just to get the AP well integrated.

Back in the good old days before Covid I had G3X/GFC500 installed with a new panel cut for about $30k, not 50s.
I think the TXi also requires Flightstream box for WIFI connection, G3X it’s built in but doesn’t do the wireless database updates.
The TXI has the high speed bus, G3X doesn’t, this is only an issue if you already use this tech.
TXi handles other hardware (like GFC 600, Stec55x, etc), but if going 500 route the G3X natively supports it.
My biggest complaint about the G3X is the slow database updates.
 
1. GFC500 driven by my G5. Great AP, but in this config, it would basically relegate my Aspen to a monitoring screen. I would actually be flying the G5.

2. GFC500 + swap out the Aspen for a TXi. This would be the dream for achieving a fully integrated panel. Idk if I can swing the cost though.

3. GFC500 + swap out the Aspen for two GI-275s. I'd have an integrated panel, but I feel like trading out an Aspen Pro Max for GI-275s would be a backwards move.

4. STEC 55x. Idk much about this AP except that a bunch of people upgraded from it to a 3100. Unfortunately, there is not an STC for the 3100 in my plane. If I went 55x, I think the pitch servo from my STEC 30 can be reused, so that would probably reduce the price of this option. I do know the 55x can integrate well with both the Aspen and the GTN.

I know a few people who have done 1., and they are happy with it. I don't think I would enjoy it too much myself, though. It works well technically but isn't great from a human factors perspective.

2. and 3. are both solid options. The TXi is obviously nicer and does more, but I've flown the #3 configuration in multiple airplanes, and I find it perfectly workable.

4.: nah, I wouldn't want to go through the expenditure and aircraft downtime only to have a previous-generation autopilot like the 55X in the plane. The 55X was a great choice ten years ago, just like the KFC200 was a great choice 20 years ago. But today, for serious IFR flying I'd go for the GFC500 or GFC600 whenever possible, and build the rest of the system around that autopilot.

- Martin
 
I think the cheapest option once you are in the STEC world, is to stay STEC as they give good credit for their installed equipment, and will "renew" your waarranty with your used servos. Do I like the Garmin GFC paired with Garmin, better ? absolutely. But its a cost factor and whether you want to go that route.

Most expensive is going to be the G500Txi, GFC500 combo. Expect easily 25K for the GFC installation by itself.

Least is using a combiantion of what you know with the aspen and upgrading the STEC. Im not a fan of aspen, but they support their products and have upgrades (just like stec) that garmin being the big elephant in the room doesnt have.
 
Have you looked into the Trio autopilot?
 
Have you looked into the Trio autopilot?

Reread the 1st post, last paragraph.
 
Reread the 1st post, last paragraph.
I believe that the Aspen will act as the nav track source for the Trio. If an analog nav source is driving the Aspen, then you can use the Aspen’s analog to digital conversion, hence digital output to drive the Trio track function.
 
Option 2 if the budget allows it, if the budget is tighter then option 3 would be my vote. I might have some used parts in the back for the Century 2 if you are interested.
 
Since it’s your money, #2. If I was paying, I’d at least try to do #3.
 
Whatever you decide for a PFD you’re going to be blown away once you fly with a complete system GFC500.
 
I think the cheapest option once you are in the STEC world, is to stay STEC as they give good credit for their installed equipment, and will "renew" your waarranty with your used servos. Do I like the Garmin GFC paired with Garmin, better ? absolutely. But its a cost factor and whether you want to go that route.

Most expensive is going to be the G500Txi, GFC500 combo. Expect easily 25K for the GFC installation by itself.

Least is using a combiantion of what you know with the aspen and upgrading the STEC. Im not a fan of aspen, but they support their products and have upgrades (just like stec) that garmin being the big elephant in the room doesnt have.
Prior to today, I would have thought you were 100% correct. That had me somewhat favoring option 4 even though I'd much rather have the GFC500 if money were no object. However, this morning, Sarasota Avionics gave me a formal quote of $47,212.50 (yep, they felt the need to get that last 50 cents in there) to do nothing except swap out the existing autopilot system for an STEC 55x. Their quote for dual GI-275s and a GFC 500 was nearly $10K less, unbelievably, and I'd be able to recoup even more by selling the Aspen.

Have you looked into the Trio autopilot?
Maybe I really should reconsider a Trio or an Aerocruze. Those quotes from Sarasota Avionics were real eye-openers. Basic modern AP that can fly 3.7 hours of a 4-hour flight for under $15K installed, or fancy AP that can fly 3.95 hours of a 4-hour flight for $35-$50K. I've flown behind an Aerocruze before and was happy with it.

I know a few people who have done 1., and they are happy with it. I don't think I would enjoy it too much myself, though. It works well technically but isn't great from a human factors perspective.
Yeah, I'm with you on that.

I might have some used parts in the back for the Century 2 if you are interested.
If my current system could be salvaged quickly and for under $1,000, I'd be game, but any more than that and I'd rather just put it toward tech that isn't a half-century old. I touched on the problem in my OP. I am happy to elaborate if you want to send me a PM.
 
if you have g5 you're halfway to the gfc500 might as well go that route. now if you just have ot upgrade, i'd go g3x again, since you have g5 you're a good deal of the way there
 
Prior to today, I would have thought you were 100% correct. That had me somewhat favoring option 4 even though I'd much rather have the GFC500 if money were no object. However, this morning, Sarasota Avionics gave me a formal quote of $47,212.50 (yep, they felt the need to get that last 50 cents in there) to do nothing except swap out the existing autopilot system for an STEC 55x. Their quote for dual GI-275s and a GFC 500 was nearly $10K less, unbelievably, and I'd be able to recoup even more by selling the Aspen.


Maybe I really should reconsider a Trio or an Aerocruze. Those quotes from Sarasota Avionics were real eye-openers. Basic modern AP that can fly 3.7 hours of a 4-hour flight for under $15K installed, or fancy AP that can fly 3.95 hours of a 4-hour flight for $35-$50K. I've flown behind an Aerocruze before and was happy with it.


Yeah, I'm with you on that.


If my current system could be salvaged quickly and for under $1,000, I'd be game, but any more than that and I'd rather just put it toward tech that isn't a half-century old. I touched on the problem in my OP. I am happy to elaborate if you want to send me a PM.

You should ask them to price the G3X/GFC500 combo, since you have a G5 already.
 
I'm not opposed to it. I just didn't think the price difference would be significant enough to merit considering the G3X over the newer piece of tech. The bulk of the cost is going to be the installation, which will require panel modification or might even mean cutting a new panel entirely. If I go all in on a project that could approach mid-five figures, a couple thousand more for the G500TXi seems trivial. I'm all ears if I'm missing something. I would much rather keep a unified, large-screen PFD than go back to two little steam-gauge-sized circles just to get the AP well integrated.
The G500TXi is a LOT more than a G3X. It does more and is a bit more configurable, but a great piece of tech.

G3X - $11,895 list
G500TXi - $17,305 list.

And the G500TXi requires a second 7" screen and setup to add Engine monitoring at another $10,960 for a 6 cylinder. G3X EIS adds $3,245 to the cost of the 10" display and doesn't require a second display.

As an aside, I like the G-5 over the GI-275 due to the rectangular screen. It just feels better.
 
If you're not pinching pennies, I would go for the GFC 500, hands down. While I haven't technically flown it, I have hundreds of hours with the GFC 700 in the Cirrus, a rock solid setup and autopilot. I've flown the STEC and am presently flying a KFC225. They are ok, but if I do it again, it's the garmin.
 
The G500TXi is a LOT more than a G3X. It does more and is a bit more configurable, but a great piece of tech.

G3X - $11,895 list
G500TXi - $17,305 list.

And the G500TXi requires a second 7" screen and setup to add Engine monitoring at another $10,960 for a 6 cylinder. G3X EIS adds $3,245 to the cost of the 10" display and doesn't require a second display.

As an aside, I like the G-5 over the GI-275 due to the rectangular screen. It just feels better.

The G5 needs to be flush mounted, otherwise its bezel sticks out.
 
While #1 is a little "weird" it's the way I'd go if this is a thing you're looking to do today.

I say that mainly because the GFC500 is hands down the best autopilot out there, but I'm not sold on the G500 TXi to drive it. The G3X Touch is significantly cheaper, can do bidirectional miscompare monitoring with the G5, and can directly drive the GFC500. The G500 TXi does have newer tech and a much nicer screen, but no monitoring and cannot drive the autopilot so a failure of the G5 would also take down your autopilot with that setup whereas having the G3X Touch and G5 both can do it so a failure of either does not take out the autopilot.

However, I feel like the G3X Touch is due for replacement before too long. It's been out for quite some time and is reaching the age at which Garmin will probably start running out of components for it in the not too distant future. With that in mind, I'd wait for the "G4X" or whatever replaces the G3X Touch as the low-end full glass solution in Garmin's lineup, provided it still has the capabilities above that distinguish the G3X Touch.

So, do the autopilot part now if you must, and patch it in with the G5. Otherwise, wait 'til after Oshkosh.
 
I'm going g3x due to already having g5s installed plus after flying behind one i'm not sure there is anything more a g500 can do, g3x is extremely nice. As for the autopilot, i'm probably gonna end up gfc500, was really wanting the aerocruz but who knows when i'd actually be able to get and install one
 
While #1 is a little "weird" it's the way I'd go if this is a thing you're looking to do today.

I say that mainly because the GFC500 is hands down the best autopilot out there, but I'm not sold on the G500 TXi to drive it. The G3X Touch is significantly cheaper, can do bidirectional miscompare monitoring with the G5, and can directly drive the GFC500. The G500 TXi does have newer tech and a much nicer screen, but no monitoring and cannot drive the autopilot so a failure of the G5 would also take down your autopilot with that setup whereas having the G3X Touch and G5 both can do it so a failure of either does not take out the autopilot.

However, I feel like the G3X Touch is due for replacement before too long. It's been out for quite some time and is reaching the age at which Garmin will probably start running out of components for it in the not too distant future. With that in mind, I'd wait for the "G4X" or whatever replaces the G3X Touch as the low-end full glass solution in Garmin's lineup, provided it still has the capabilities above that distinguish the G3X Touch.

So, do the autopilot part now if you must, and patch it in with the G5. Otherwise, wait 'til after Oshkosh.

Other than improving database update performance what do you want from it? It’s not like you are going to watch 4K movies so screen improvements wouldn’t be necessary? Integration of satellite imagery into the synthetic vision?
What does the new G1000 or even the G3000 do (applicable to pistons) that the G3X can’t do?
 
Other than improving database update performance what do you want from it? It’s not like you are going to watch 4K movies so screen improvements wouldn’t be necessary? Integration of satellite imagery into the synthetic vision?
What does the new G1000 or even the G3000 do (applicable to pistons) that the G3X can’t do?
Better resale value in the next 10 years... And yes, more features that we don't even know about.

For example, I got a GTN 750 in late 2017. Then they came out with the 750Xi: Higher resolution, brighter display, updated CPU, faster map rendering, smoother panning, faster startup, all merely nice-to-haves. But then, they came out with Smart Glide which is only available on the Xi for example, and they're still adding features to the Xi where the standard GTNs aren't really getting new software features.

It may not happen with the "G4X", but I do expect that Garmin's autoland system, or at least a workable subset thereof, will migrate down to the piston retrofit market at some point, and it's going to require the latest greatest avionics. And I'd expect that there will be more screen and less bezel with the "G4X", making it easier to read.
 
While #1 is a little "weird" it's the way I'd go if this is a thing you're looking to do today.

I say that mainly because the GFC500 is hands down the best autopilot out there, but I'm not sold on the G500 TXi to drive it. The G3X Touch is significantly cheaper, can do bidirectional miscompare monitoring with the G5, and can directly drive the GFC500. The G500 TXi does have newer tech and a much nicer screen, but no monitoring and cannot drive the autopilot so a failure of the G5 would also take down your autopilot with that setup whereas having the G3X Touch and G5 both can do it so a failure of either does not take out the autopilot.

However, I feel like the G3X Touch is due for replacement before too long. It's been out for quite some time and is reaching the age at which Garmin will probably start running out of components for it in the not too distant future. With that in mind, I'd wait for the "G4X" or whatever replaces the G3X Touch as the low-end full glass solution in Garmin's lineup, provided it still has the capabilities above that distinguish the G3X Touch.

So, do the autopilot part now if you must, and patch it in with the G5. Otherwise, wait 'til after Oshkosh.
The G3X's age also underscores the general concept of obsolescence. I have a panel that, aside from the AP, was recut and fitted with a modern avionics suite in 2018. The Aspen got the Max update less than three years ago. My panel situation is not comparable to someone who is planning an upgrade path from an old six pack, and yet the GFC 500 cost would be similar. It feels wasteful to gut non-obsolete avionics and cut a new panel so soon over what amounts to a glorified compatibility issue Garmin artificially created. The only way to do a GFC 500 without pulling perfectly good avionics is option #1, which as you so aptly put, is weird.

I am surprised to be saying that the lowly Trio seems to be the natural fit. I did learn, and was previously unaware, that the Trio is certified to do RNAV approaches down to 500' AGL when coupled with the avionics I already have. It fully integrates with my current avionics package, and can be installed out-the-door for $10-12K. Most of my approaches are RNAVs, and it's not like I'm out there shooting tons of approaches to mins single-pilot IFR in a non-deiced piston single lol.

Maybe some of the money I save with the Trio would be well-spent upgrading the GTN 750 to the Xi. As you point out, it is a nice step up from the original 750.

Thanks everyone for the discussion and input.
 
I'm going g3x due to already having g5s installed plus after flying behind one i'm not sure there is anything more a g500 can do, g3x is extremely nice. As for the autopilot, i'm probably gonna end up gfc500, was really wanting the aerocruz but who knows when i'd actually be able to get and install one
If you're interested in the AeroCruze, I just checked on AeroPerformance/Spruce Tuesday and they have availability of all 3 controllers - stack, 2 1/2 and 3 1/8.
 
Most people don't fully realize the GFC-500 is a GPS only A/P. It will track a Localizer or VOR, but with GPS. If GPS fails either due to a panel issue or satellite outage, it reverts to PIT & ROL mode set to last roll and pitch from the GPS. The 500 will still accept headings and pitch rate if GPS is out. So "vectors to final" still works to reduce workload.

Only the GFC-600 will genuinely track a green needle, the GFC-500 will not but will pretend too. That being said the GFC-500 will smoke an AeroCruze or Trio in anyway it's measured.
 
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However, I feel like the G3X Touch is due for replacement before too long. It's been out for quite some time and is reaching the age at which Garmin will probably start running out of components for it in the not too distant future. With that in mind, I'd wait for the "G4X" or whatever replaces the G3X Touch as the low-end full glass solution in Garmin's lineup, provided it still has the capabilities above that distinguish the G3X Touch.
I figured that the replacement would be announced at Oshkosh as my plane was completed in June. :D

But I figure that even if it comes out shortly, there will be a good window to upgrade and sell the G3X I have
 
Most people don't fully realize the GFC-500 is a GPS only A/P. It will track a Localizer or VOR, but with GPS. If GPS fails either due to a panel issue or satellite outage, it reverts to PIT & ROL mode set to last roll and pitch from the GPS. The 500 will still accept headings and pitch rate if GPS is out. So "vectors to final" still works to reduce workload.

Only the GFC-600 will genuinely track a green needle, the GFC-500 will not but will pretend too. That being said the GFC-500 will smoke an AeroCruze or Trio in anyway it's measured.
I’m pretty sure that is not correct.
 
I don't get what more could i want than a g3x, if it uses all my equip, what more? thing does just about everything
why bother worrying about what's next, fly now.
 
Most people don't fully realize the GFC-500 is a GPS only A/P. It will track a Localizer or VOR, but with GPS. If GPS fails either due to a panel issue or satellite outage, it reverts to PIT & ROL mode set to last roll and pitch from the GPS. The 500 will still accept headings and pitch rate if GPS is out. So "vectors to final" still works to reduce workload.
Only the GFC-600 will genuinely track a green needle, the GFC-500 will not but will pretend too. That being said the GFC-500 will smoke an AeroCruze or Trio in anyway it's measured.
I’m pretty sure that is not correct.

Pretty big topic and posting to a fresh thread: https://www.pilotsofamerica.com/community/threads/gfc-500-is-a-gps-only-autopilot.149393/
 
Does it automatically revert to those modes? Does it revert back when signal is gained?

I ask because I’ve had one instance of GPS signal dropping for about 5 seconds and it affecting my old school non-Garmin nav set-up. Once the signal came back, all was normal again. The A/P reaction was not good for that 5 seconds, but that’s a different story.
 
Prior to today, I would have thought you were 100% correct. That had me somewhat favoring option 4 even though I'd much rather have the GFC500 if money were no object. However, this morning, Sarasota Avionics gave me a formal quote of $47,212.50 (yep, they felt the need to get that last 50 cents in there) to do nothing except swap out the existing autopilot system for an STEC 55x. Their quote for dual GI-275s and a GFC 500 was nearly $10K less, unbelievably, and I'd be able to recoup even more by selling the Aspen.


Maybe I really should reconsider a Trio or an Aerocruze. Those quotes from Sarasota Avionics were real eye-openers. Basic modern AP that can fly 3.7 hours of a 4-hour flight for under $15K installed, or fancy AP that can fly 3.95 hours of a 4-hour flight for $35-$50K. I've flown behind an Aerocruze before and was happy with it.


Yeah, I'm with you on that.


If my current system could be salvaged quickly and for under $1,000, I'd be game, but any more than that and I'd rather just put it toward tech that isn't a half-century old. I touched on the problem in my OP. I am happy to elaborate if you want to send me a PM.
Check out this thread- you may find an easy solution if its just the connector. https://miscsolutions.wordpress.com/2011/02/16/troubleshooting-old-century-autopilots/
 
Check out this thread- you may find an easy solution if its just the connector. https://miscsolutions.wordpress.com/2011/02/16/troubleshooting-old-century-autopilots/
Thanks. I think I stumbled onto that site sometime in the past when I was troubleshooting the old Century on a previous plane. Very good info for those who want to try to salvage their Century. I may try some of the easier fixes on that site and that people here have suggested (particular thanks to Jacob Kinsey) to get the Century working at least on an interim basis, but it's getting pulled. Tom J is installing a Trio for me in January. I am excited to see if it integrates as well with the Aspen and GTN as Trio/Aspen claim it will.
 
Does it automatically revert to those modes? Does it revert back when signal is gained?
Based on what I've read, I believe the answers are yes and no.
I ask because I’ve had one instance of GPS signal dropping for about 5 seconds and it affecting my old school non-Garmin nav set-up. Once the signal came back, all was normal again. The A/P reaction was not good for that 5 seconds, but that’s a different story.
If it's reverting to ROL and PIT, it's not going to go nuts on you during that 5 seconds, it's going to hold steady... But you'll need to put it back in the appropriate modes.
 
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