What value placed on IFR GPS w/autopilot

[Tony_Scarpelli]

I know it sort of depends on the exact units so here are a couple of senarios.

King 89B with altimac IIIC working

King 94 with altimac IIIC all working

Garmin 430W w Stec30

All things equal if you saw a bird that you would love to have but one has the GPS/autopilot and the other is still IFR but not GPS and autopilot.

What number would you place above and beyond for the three options above.

Assume it is on a Xcountry single retract like 177RG, Arrow, Comanche, Bo etc...

 

[JimNtexas]

The 430/Stec costs over $14,000 to install in a PA28. Certainly it adds at least half that much value to a used plane, maybe more.

The 89b or 94 would be worth $5K to me, maybe because I routinely fly with an 89b. It might be worth less to a Garmin only pilot.

Altimac III is worth nothing to me, since even if the seller has it working today, it will fail tomorrow.

 

[Ted]

If it doesn't have a 430/530, then the avionics isn't worth much to me. So for option 3, I'd maybe add $5-10k to purchase price.

Really I'd want to find a plane with a 530 at minimum. Or, if it had a 430, it should be in such an arrangement that adding a 530 would be easy enough.

 

[wabower]

Hey, Tony, isn't this where we left off two years ago?
QUOTE=Tony_Scarpelli;1050236]I know it sort of depends on the exact units so here are a couple of senarios.

King 89B with altimac IIIC working

King 94 with altimac IIIC all working

Garmin 430W w Stec30

All things equal if you saw a bird that you would love to have but one has the GPS/autopilot and the other is still IFR but not GPS and autopilot.

What number would you place above and beyond for the three options above.

Assume it is on a Xcountry single retract like 177RG, Arrow, Comanche, Bo etc...[/QUOTE]

 

[Clark1961]

Altimac III is worth nothing to me, since even if the seller has it working today, it will fail tomorrow.

??? The altimatic IIIC has a problem with servo parts availability but the computer and trim amp are fairly reliable and repairable with off the shelf parts. All I'm saying is my experience with the 'kota has been different. I firmly believe the competence and experience of the folks working on the IIIC has a lot to do with longevity.

With that said, I've flown the IIIC with a 90B (not on the list, I know) and a 430W. I much prefer the 430W and consider the pair worth somewhere in the range of 10 to 20 AMU. It drops to about 10 AMU with the 90B. I have no experience with STEC autopilots.

 

[AcroBoy]

I have a 430W and Stec 30 with altitude hold. The 430W is of course great, but the STEC 30 wanders and searches a lot until it finally starts tracking. It is a lot better than your basic wing leveler.

As for the old King stuff- not in the same league as a 430w, and a lot farther yet from a 530W.

Of course all this is driven by budget and mission requirements

 

[wabower]

Do you have the GPSS module for the Stec?

I have a 430W and Stec 30 with altitude hold. The 430W is of course great, but the STEC 30 wanders and searches a lot until it finally starts tracking. It is a lot better than your basic wing leveler.

As for the old King stuff- not in the same league as a 430w, and a lot farther yet from a 530W.

Of course all this is driven by budget and mission requirements

 

[AcroBoy]

No GPSS, and not really needed. It's on an Extra, and the only real use is to enable me to look at a chart or something else without the plane rolling, climbing, or diving.

The older KFC 200 I also have is much more stable and tracks better, also without GPSS.

 

[azure]

FWIW, my experience with my Stec-30 is similar to Jim N's -- when trying to intercept a VOR or LOC, it basically doesn't, unless you're already established. The turns it makes are so anemic that it blows right through the course. Once it's on course it does an okay job of tracking it. It's much better at intercepting and tracking a GPS-defined course, though it never turns at more than about 3/4 standard rate (usually more like half standard rate). Either way it is passably good at holding a GS.

I'm a little worried about what to do on the checkride BTW, since if the examiner wants me to fly a coupled VOR approach from 10 degrees off course, it won't do it worth a darn unless I intercept by hand first.

 

[Ted]

FWIW, my experience with my Stec-30 is similar to Jim N's -- when trying to intercept a VOR or LOC, it basically doesn't, unless you're already established. The turns it makes are so anemic that it blows right through the course. Once it's on course it does an okay job of tracking it. It's much better at intercepting and tracking a GPS-defined course, though it never turns at more than about 3/4 standard rate (usually more like half standard rate). Either way it is passably good at holding a GS.

I'm a little worried about what to do on the checkride BTW, since if the examiner wants me to fly a coupled VOR approach from 10 degrees off course, it won't do it worth a darn unless I intercept by hand first.

Tell him as such. Shows you know your plane. If he questions it, let him try.

 

[wabower]

I knew in advance that the 30A wouldn't track particularly well without the GPSS module, but that it shouldn't matter (much) since I could make it do whatever I wanted with the heading bug, and tracking a nav signal works fine once established on course. YMMV.

FWIW, my experience with my Stec-30 is similar to Jim N's -- when trying to intercept a VOR or LOC, it basically doesn't, unless you're already established. The turns it makes are so anemic that it blows right through the course. Once it's on course it does an okay job of tracking it. It's much better at intercepting and tracking a GPS-defined course, though it never turns at more than about 3/4 standard rate (usually more like half standard rate). Either way it is passably good at holding a GS.

I'm a little worried about what to do on the checkride BTW, since if the examiner wants me to fly a coupled VOR approach from 10 degrees off course, it won't do it worth a darn unless I intercept by hand first.

 

[flyingron]

For me the autopilot is secondary to having a solid moving map. I'd take the 430W with the most rudimentary autopilot over either of those King units. WAAS and the better display swamps even a top notch autopilot on a less capable navigator.

 

[dell30rb]

For me the autopilot is secondary to having a solid moving map. I'd take the 430W with the most rudimentary autopilot over either of those King units. WAAS and the better display swamps even a top notch autopilot on a less capable navigator.

I'll agree with you there...

My cross country plane now is a Warrior II with a GTN-650 and the simple piper autopilot, it will hold the heading set with the bug to about + or - 5 degrees. I can't see any situation where a better, coupled autopilot would make a big difference. Fatigue is rarely an issue for me.


Having LPV approaches is worth much more to me than a really good AP

 

[JimNtexas]

when trying to intercept a VOR or LOC, it basically doesn't, unless you're already established.

That's because the STEC 20/30 does not have intercept capability. If you read the manual you'll see that the pilot must be tracking within ten degrees of the VOR/ILS/GPS course before engaging track mode.

I regularly fly a Cardinal and an Archer with an STEC, and find they both track ILS and GPS pretty well if you engage tracking after you are established on course.

Neither of the STEC's I use can track a VOR, but really, who cares?

Our partnership stupidly (IMHO) saved a couple of bucks and passed on installing the GPS Steering module.

If intercepting with your STEC is important to you then that's what you want.

 

[Marauder]

That's because the STEC 20/30 does not have intercept capability. If you read the manual you'll see that the pilot must be tracking within ten degrees of the VOR/ILS/GPS course before engaging track mode.

I regularly fly a Cardinal and an Archer with an STEC, and find they both track ILS and GPS pretty well if you engage tracking after you are established on course.

Neither of the STEC's I use can track a VOR, but really, who cares?

Our partnership stupidly (IMHO) saved a couple of bucks and passed on installing the GPS Steering module.

If intercepting with your STEC is important to you then that's what you want.

I believe Jim is correct, the higher end models have the "capture" capabilities. My 60-2 will setup for a VOR intercept. Here is the POH excerpt on VOR tracking:

NOTE: If the VOR needle is at full-scale deviation, the autopilot will establish a 45o intercept angle to the desired course. As the aircraft approaches the selected radial, the autopilot senses the closure rate, and gradually, smoothly shallows the intercept angle. The point at which this turn begins is variable, depending on the aircraft position and closure rate to the radial. However, the turn will always begin between 100% (full-scale) needle deflection and 20% of full- scale. During the intercept sequence, the system operates in maximum gain and sensitivity to needle position and can command 90% of a standard rate turn.
When the selected course is intercepted and the needle is within 15% of centered, the CAP annunciator illuminates indicating course capture and initiation of the tracking gain sequence. This high sensitivity level is maintained for approximately 15 seconds while wind correction angle is established. Turn rate capability is then reduced to 45% standard turn rate (Capture/Soft Gain) identified by both the CAP and SOFT annunciation's.

Not sure the 20 or 30 versions do this.

 

[Tony_Scarpelli]

Yeah, still haven't pulled the trigger. Probably won't.

Hey, Tony, isn't this where we left off two years ago?
QUOTE=Tony_Scarpelli;1050236]I know it sort of depends on the exact units so here are a couple of senarios.

King 89B with altimac IIIC working

King 94 with altimac IIIC all working

Garmin 430W w Stec30

All things equal if you saw a bird that you would love to have but one has the GPS/autopilot and the other is still IFR but not GPS and autopilot.

What number would you place above and beyond for the three options above.

Assume it is on a Xcountry single retract like 177RG, Arrow, Comanche, Bo etc...

[/QUOTE]