S-Tec 55X interfaced with the G1000 Ovation

[donkaye]

I was up in Canada last week doing a transition training with a student who had just purchased a G1000 Ovation with the S-Tec autopilot.  Does anyone know if the early G1000 with the S-Tec 55X autopilot has Altitude Preselect? I was able to get the V/S preselect to work, but not the Altitude Preselect.  I selected the Altitude on the G1000 and simultaneously pushed the ALT and V/S buttons as I have done in other installations of the S-Tec, but the ALT light would not light and, therefore, not arm the altitude preselect.

Thanks.

[Robert C.]

Don,

Yep, (pre-select) set the altitude on the G1000 with the altitude selector (rotating) knob and then when climbing/descending press ALT and V/S as you describe for altitude capture. Works like a charm in mine. It can be a little finicky about (me) pressing the Alt and V/S buttons simultaneously so sometimes I have to do it twice but I consider that more of an operator-error thing and is not an avionics problem.

Sounds like he may have a A/P problem and may need an avionics shop to take a look at his S-Tec.

Robert

 

 

[donkaye]

Thanks, Robert.  Does the plane really need to be in the climb before engaging ALT?  In other words, you're saying preselect the altitude, engage VS and THEN ALT and V/S together after the plane begins climbing.  I have another student who has the G500 and just follows the procedure I originally stated. That was not the case with this plane.

[Danb]

Don I have one of the earlier models and yes it does have stec /alt alert/ selection.

No it doesn't have to be in a climb to engage alt mine can be in a climb,descent or level flight to engage the system.

[mike_elliott]

16 hours ago, donkaye said:

I was up in Canada last week doing a transition training with a student who had just purchased a G1000 Ovation with the S-Tec autopilot.  Does anyone know if the early G1000 with the S-Tec 55X autopilot has Altitude Preselect? I was able to get the V/S preselect to work, but not the Altitude Preselect.  I selected the Altitude on the G1000 and simultaneously pushed the ALT and V/S buttons as I have done in other installations of the S-Tec, but the ALT light would not light and, therefore, not arm the altitude preselect.

Thanks.

should work

[PaulM]

Stec must be in HDG or NAV mode first... Select the VS mode next.. dial in the VS you want via the knob.. and then press VS.. +ALT  and that engages the selector from the G1000.   It will slow down the VS when within about 200ft of the capture alt.   

I always press and hold the VS button first and then press the ALT button and adjust the VS via the knob. 

 

 

[Robert C.]

On 6/28/2016 at 0:31 AM, donkaye said:

Thanks, Robert.  Does the plane really need to be in the climb before engaging ALT?  In other words, you're saying preselect the altitude, engage VS and THEN ALT and V/S together after the plane begins climbing.  I have another student who has the G500 and just follows the procedure I originally stated. That was not the case with this plane.

 

I actually don't know the answer. Guess I fell into the habit of doing it in 2 stages. Will try and remember to test it next time I fly.

[dvk]

Does anybody know how the ALT capture works in the combination G1000 + STEC 55x?

I mean, how the G1000 sends the information about what is the selected ALT? Is that a kind of "table" of voltage and feet? Do you know which pin the G1000 is connected with the STEC55X computer for this purpose?

Just curious, and perhaps could help me diagnose and issue with my AP.

Thanks.