S-Tec upgrade ??

DKirkpatrick

DKirkpatrick

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DKirkpatrick
Hello. Looking at a C182... 14Vdc airplane. It has an S-Tec 20 and has altitude hold. I'm pretty ignorant on autopilots... but, my understanding is the S-Tec 20 is a single-axis autopilot. Is there a simple upgrade to S-Tec XX (?) to get me a two axis autopilot?
Would like to be able to track GPS RNAV approaches.
thanks!
—dan
 
You've got two problems. The System 20 won't really track GPS well enough to do approaches. You can add an ST-901 to get GPSS capability in the horizontal access.
The system 30 ALT upgrade will give you altitude hold, but won't track a glideslope. You'll need to go to the System 60 PSS to get GS tracking as an add-on.
By the time you do all that you may find it cheaper just to switch to a 55-x or the like.
 
I have a 55X in a 210 and I like it alot. Reckon what switching from the S-20 to the 55-X would cost?
I know it'll be some bucks, but approaches w RNAV on a bad day are just hard to beat...
Thanks for your counsel.
 
You might be best served to pull the S-Tec and install a BK AeroCruze 100.
 
You might look into the new stec 3100. Can use your your current servos. Fairly simple. Not cheap.
 
Chip Sylverne said:
You might look into the new stec 3100. Can use your your current servos. Fairly simple. Not cheap.
Click to expand...

I had a conversation with an S-Tec rep about upgrading from my S-Tec 60 to a 3100. The cost was prohibitive. It was far less expensive to simply start from scratch with the BK AeroCruze 100.
 
If you have altitude hold and can add GPSS capability, that's a fine AP. I have the STEC 30, same as the 20 but with altitude hold. At least that's my understanding of their nomenclature. I was thinking about upgrading to the Garmin AP to get vertical guidance. I decided against it as mine can fly approaches pretty well, RNAV, LOC and VOR providing horizontal guidance. I can manage the vertical. It's also easy to do the switching needed to move from vectors to joining the approach. The cost of upgrading is substantial if you stay STEC and the Garmin unit will likely be in the $20k region from installation and adding a G5 that's required to run it.

Just one opinion, particularly if budget is an issue.
 
I have a perfectly functioning Stec system 60 and whichever upgrade option I looked at to make it 2 axis ended up as several (many?) thousands more than just starting afresh with a Trutrak/Bendix or a Trio. I still haven't pulled the trigger but will after this summer. Leaning Trio for the moment but truly undecided except for the firm decision that upgrading the Stec makes no sense at all.
 
Alien Mind said:
I have a perfectly functioning Stec system 60 and whichever upgrade option I looked at to make it 2 axis ended up as several (many?) thousands more than just starting afresh with a Trutrak/Bendix or a Trio. I still haven't pulled the trigger but will after this summer. Leaning Trio for the moment but truly undecided except for the firm decision that upgrading the Stec makes no sense at all.
Click to expand...

+1
 
Alien Mind said:
I have a perfectly functioning Stec system 60 and whichever upgrade option I looked at to make it 2 axis ended up as several (many?) thousands more than just starting afresh with a Trutrak/Bendix or a Trio. I still haven't pulled the trigger but will after this summer. Leaning Trio for the moment but truly undecided except for the firm decision that upgrading the Stec makes no sense at all.
Click to expand...

Both (trio/trutrak) are good economical options, but with some limitations that the S-tec and Garmin don't have. While they are both capable of being coupled to GPS for approaches, neither is currently allowed to be coupled on an approach by their AFMS's and have much higher minimum engagement altitudes. Neither will track VHF nav at all, only GPS. In this day and age, that's less of an issue, but is still something to be aware of.

If you aren't flying IFR or are content hand flying your approach (or are fine ignoring paper restrictions) they can be very low cost autopilots that relieve a great deal of burden of hand flying the enroute section of a flight. While they may go through the hoops to certify lower altitudes and approach coupling at some point down the road (with potential software and/or hardware changes needed), I would say don't buy something on the hopes of what it might do down the road.

For the OP about upgrading the S-tec 20 to 2 axis, you'd probably do better just pull it and go with a GFC 500... the upgrade to a 3100 wouldn't be cost effective I don't think and adding on the 2nd axis with a 60 PSS or whatnot isn't as nicely integrated.

I do think S-tec was offering some discounted 55X upgrades at one point, to resell all the 55X controllers that were coming in from folks upgrading to the 3100. You might want to reach out to Doug Tellef about that.
 
flyingron said:
You've got two problems. The System 20 won't really track GPS well enough to do approaches. You can add an ST-901 to get GPSS capability in the horizontal access.
The system 30 ALT upgrade will give you altitude hold, but won't track a glideslope. You'll need to go to the System 60 PSS to get GS tracking as an add-on.
By the time you do all that you may find it cheaper just to switch to a 55-x or the like.
Click to expand...
Slight correction: the STEC-20 by itself won't intercept or take you around turns, but once you've intercepted, it will keep you within tolerance by chasing CDI deviation (either driven by a localiser or the GPS).

However, fully agree that the STEC-20 is much nicer with the ST-901 GPSS -- with that, it will take you around turns, fly a hold or arc, etc. etc. Also agreed that there's no obvious upgrade path to a full 2- or 3-axis autopilot (with GS tracking). The only exception might be that you can keep your current STEC-20/30 servos when you upgrade (I'm not sure about that, though).
 
Hang 4 said:
If you have altitude hold and can add GPSS capability, that's a fine AP. I have the STEC 30, same as the 20 but with altitude hold. At least that's my understanding of their nomenclature. I was thinking about upgrading to the Garmin AP to get vertical guidance. I decided against it as mine can fly approaches pretty well, RNAV, LOC and VOR providing horizontal guidance. I can manage the vertical. It's also easy to do the switching needed to move from vectors to joining the approach. The cost of upgrading is substantial if you stay STEC and the Garmin unit will likely be in the $20k region from installation and adding a G5 that's required to run it.

Just one opinion, particularly if budget is an issue.
Click to expand...
I don't have the 30, but I still agree. While it would be nice, sometimes, to have a 2-axis A/P, the STEC-20 does most of what I need (even without the altitude hold), and is also fully independent of the vacuum system, just like newer A/Ps are. I can't justify spending the AMUs to rip it out and put in a GFC 500 (the TT isn't an attractive option for me, because I'd be downgrading from an A/P that's certified for IFR approaches to one that isn't, even though the TT has great functionality and price).
 
David Megginson said:
Slight correction: the STEC-20 by itself won't intercept or take you around turns, but once you've intercepted, it will keep you within tolerance by chasing CDI deviation (either driven by a localiser or the GPS).
Click to expand...
It doesn't have the tolerance inside the FAF to be legally used for approaches however.
 
Adding G5s will make the STEC-20 a pretty capable 1 axis AP for iFR. I still hand fly final approaches, but the G5 GPSS emulation does a great job with HILPTs and course reversals.
 
I started with the STec 20/30, then added the 60 PSS altitude hold with auto trim then the ST 901 for GPSS and finally the ST-360 for altitude pre-select and alert. Dual G5s provide the lateral and vertical course guidance from my GNS 530W. The system now will fly a GPSS (or VOR) route, intercept the final approach course, capture and follow the glide slope (or LPV) and at DH will climb to the missed altitude and follow the routing. Took a number of years to get here with the only "throw away" being the ST 901 because the G5s provide GPSS input. A lot of the cost for installing any autopilot is in the servo mounting, etc. So piece meal upgrades as I did are not terribly expensive. I'd like the STec 3100 but Genesys has no plans to pursue an STC for the Piper PA 28 series and I'm not willing to spend a lot of $$ to have all the STec servos as well as computer, etc. removed and replaced with Brand X equipment.
 
flyingron said:
It doesn't have the tolerance inside the FAF to be legally used for approaches however.
Click to expand...
no such limitation in the manual for the STEC 20/30. Source?
 
(Update: I didn't see @flyingron 's subsequent reply until after I posted this. They've already checked the AFMS and confirmed the same point.)

flyingron said:
It doesn't have the tolerance inside the FAF to be legally used for approaches however.
Click to expand...
What's your source for that? There's no approach restriction in my STEC-20 AFMS against using the STEC-20 for an approach. The only operating limitations are airspeed (not above 140 KIAS for my PA-28-161, which would be a steep dive in any case), and not to use it for actually taking off or landing (i.e. don't have it on when the wheels are in contact with the ground, as is the case with any GA autopilot). The AFMS specifically includes procedures for different kinds of intstrument approaches, with VOR, LOC, or GPS, and there's no mention of turning it off at the FAF.

The instructions in the STEC-20/30/30alt Pilot's Information Manual (which are not legal limitations, unlike the "Operating Limitations" section of the AFMS) also show approaches in great detail, with diagrams. Again, no mention of turning it off at the FAF. The only mention of disconnecting the A/P during an approach is this:

Note
If a missed approach is declared at the middle marker
2. A. Disconnect the autopilot and stabilize the aircraft for the missed approach.
B. Select the HDG mode
Click to expand...
 
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Good Afternoon,

We (Genesys/S-TEC) do have an upgrade path from the legacy S-TEC systems to the S-TEC 3100. The price will depend on which S-TEC system you have installed and in all cases you will get a new 2 year warranty on all the new components as well as a fresh 1 year warranty on your existing S-TEC servo(s) regardless of how old they are. Additionally, during the upgrade your existing servos will be inspected and if they are found to be needing service/repair/overhaul that will be taken care of under the 3100 warranty at no cost to you.

Genesys Aerosystems S-TEC 3100 is a fully featured, attitude-based autopilot that gives you a list of workload-reducing and safety-enhancing capabilities that were previously unavailable on aftermarket autopilots. Compatible with traditional steam gauges or advanced digital sources & EFIS displays from various manufacturers, the S-TEC 3100 delivers unmatched features and benefits:


· Precise, digital flight control for every phase of flight
· 2-axis (3-axis option on some models)
· Automatic Trim included
· Envelope Protection/Alerting*
· Straight and Level Recovery
· Precision Approaches/Missed Approaches
· Indicated Airspeed Hold*
· Altitude Preselect*
· And much more!

*Additional equipment may be required in some configurations


For more information on the 3100 please view this link:
https://genesys-aerosystems.com/products/s-tec-3100-digital-flight-control-system

You can find a list of S-TEC dealers here if you would like to call around to check on install prices and shop availability:
https://genesys-aerosystems.com/dealer-locator

Please let me know if I can provide any more information. Thank you.
 
Doug Tellef said:
Good Afternoon,

We (Genesys/S-TEC) do have an upgrade path from the legacy S-TEC systems to the S-TEC 3100. The price will depend on which S-TEC system you have installed and in all cases you will get a new 2 year warranty on all the new components as well as a fresh 1 year warranty on your existing S-TEC servo(s) regardless of how old they are. Additionally, during the upgrade your existing servos will be inspected and if they are found to be needing service/repair/overhaul that will be taken care of under the 3100 warranty at no cost to you.

Genesys Aerosystems S-TEC 3100 is a fully featured, attitude-based autopilot that gives you a list of workload-reducing and safety-enhancing capabilities that were previously unavailable on aftermarket autopilots. Compatible with traditional steam gauges or advanced digital sources & EFIS displays from various manufacturers, the S-TEC 3100 delivers unmatched features and benefits:


· Precise, digital flight control for every phase of flight
· 2-axis (3-axis option on some models)
· Automatic Trim included
· Envelope Protection/Alerting*
· Straight and Level Recovery
· Precision Approaches/Missed Approaches
· Indicated Airspeed Hold*
· Altitude Preselect*
· And much more!

*Additional equipment may be required in some configurations


For more information on the 3100 please view this link:
https://genesys-aerosystems.com/products/s-tec-3100-digital-flight-control-system

You can find a list of S-TEC dealers here if you would like to call around to check on install prices and shop availability:
https://genesys-aerosystems.com/dealer-locator

Please let me know if I can provide any more information. Thank you.
Click to expand...

Doug, what are the minimum and maximum dollars this upgrade would cost? Use my Cessna 182 with an S-Tec 60 as an example.

Thanks!
 
The current upgrade pricing is as follows:

Upgrades from a legacy S-TEC system w/ trim already installed:
Single axis to 3100 - $12,495
Dual axis to 3100 - $10,495
55X to 3100 - $9,995

If you do not already have a S-TEC electric trim installed that will add $1,500 to the above prices as auto-trim (including a manual electric trim switch) comes standard on the 3100.

For customers who do not have a legacy S-TEC system installed a complete system is $19,995. An optional integrated yaw damper can be added for $5,000. (yaw is not avaialable on the Cessna 177 and 182 series or the PA-24 series)
 
Doug Tellef said:
For customers who do not have a legacy S-TEC system installed a complete system is $19,995. An optional integrated yaw damper can be added for $5,000. (yaw is not avaialable on the Cessna 177 and 182 series or the PA-24 series)
Click to expand...
Thanks for sharing that. It's interesting to compare pricing

GFC 500:

base unit - $7,000
G5 (if not already installed) - $3,000
Electric trim: $2,000
Yaw damper: $3,000

S-TEC 3100:
Base unit - $20,000 (already includes electric trim)
Yaw damper - $5,000

So a comparable GFC 500 system to the S-TEC 3100 without yaw damping would be $12,000 vs $20,000. With yaw damping, it would be $15,000 vs $25,000.

Since I have an S-TEC 20 (one servo, no electric trim), I could upgrade to the S-TEC 3100 for $12,500 + $1,500 for the trim, which would come out to $14,000 --- still more than purchasing a comparable GFC system, but closer (and I might save a bit on installation by leaving the S-TEC servo in place; not sure).

It would be great to have a full-IFR autopilot in competition with the GFC 500 (the TT/Aerocruze 100 is too limited for many IFR pilots), but I think the $8K-10K price delta puts the S-TEC 3100 out of reach. I've been thrilled with the reliability of my S-TEC 20 over the past 10 years, and when it does come time to upgrade (which won't be soon, I hope), I'd seriously consider another S-TEC unit if the price were comparable with the GFC 500.
 
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Actually, as I've been thrilled with the flawlessness of my venerable old Stec, I'd be quite prepared to pony up the extra $$ to upgrade to the amazing 3100 instead of the somewhat limited Trio/Trutrak - BUT, for some reason, Stec haven't got an STC for a PA28! (unless, of course, Doug has some secret knowledge on 'coming soon'?)
 
David Megginson said:
Thanks for sharing that. It's interesting to compare pricing

GFC 500:

base unit - $7,000
G5 (if not already installed) - $3,000
Electric trim: $2,000
Yaw damper: $3,000

S-TEC 3100:
Base unit - $20,000 (already includes electric trim)
Yaw damper - $5,000

So a comparable GFC 500 system to the S-TEC 3100 without yaw damping would be $12,000 vs $20,000. With yaw damping, it would be $15,000 vs $25,000.

Since I have an S-TEC 20 (one servo, no electric trim), I could upgrade to the S-TEC 3100 for $12,500 + $1,500 for the trim, which would come out to $14,000 --- still more than purchasing a comparable GFC system, but closer (and I might save a bit on installation by leaving the S-TEC servo in place; not sure).

It would be great to have a full-IFR autopilot in competition with the GFC 500 (the TT/Aerocruze 100 is too limited for many IFR pilots), but I think the $8K-10K price delta puts the S-TEC 3100 out of reach. I've been thrilled with the reliability of my S-TEC 20 over the past 10 years, and when it does come time to upgrade (which won't be soon, I hope), I'd seriously consider another S-TEC unit if the price were comparable with the GFC 500.
Click to expand...
Update: I realised afterwards that the S-TEC 3100 is really more in competition with Garmin's GFC 600, so the price comparison with the GFC 500 wasn't quite fair. Maybe they'll release a lower-priced GFC 500 competitor in the future (?)

To bad neither the Trio nor the Bendix-King AeroCruze 100 has IFR approach certification. Garmin is really the only game in town for an IFR PA-28. :(
 
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