TBM 930 FLC doesn't work for descend

Discussion Hub General Discussion
1

Hi, I find out that FLC does not work if I set an altitude lower than the current one for more than couple hundreds feet. Yes, I did decrease the throttle, however, the plane just changes to the current alt rather than pitch down. It works when I want to increase the alt. Has anyone encountered this issue?

Screenshot (8)
Screenshot (8)2583Ă—1405 2.34 MB

2

you need to use vertical speed (VS) for descent

3

But FLC works perfectly fine on other Garmin G1000 equipped planes, is it a bug or I did it wrong?

1 Like
4

Thanks for including a screen shot. Everything is set up correctly, so would recommend an official bug report with the screenshot attached. A link to ZenDesk is in the top menu bar.

5

Thanks Mod. I just submitted a request through Zendesk. Hope the dev could address this issue.

1 Like
6

FLC should work for decents too.

8

Yeah, FLC descending works on other planes, such as the Cessna 172 based on my experience. However, it just flats out not responsive to me on TBM 930.

1 Like
9

Works perfectly for me. Dial up the lower alt, hit FLC, drop the throttle and dial the required speed - down she goes and holds the selected speed until she stabilises at the requested alt.

Check that the speed you request combined with throttle setting is actually achievable.

2 Likes
10

In the screenshot I posted. I first dialed alt to 20,000 feet when I was cruising at 22,000 using 99% torque. Then I hit FLC, the FLC speed is set to my current speed of 221KT. After that, I reduce the throttle to 7% torque. The airspeed dropped to 178 without pitching down. You can see in the screenshot the descending rate was literately 0.

11

Reducing throttle is required IRL also i believe ?

12

Weird, wirks fine this for me. I have a lot of issues with procedures. I cannot delete fixes, most of routes are longer, sometimes this thing makes a triangle route. But flc works

13

Reducing throttle is required IRL also i believe ?

Technically the autopilot only knows current airspeed and desired airspeed, and adjusts pitch based on the difference between the two. Throttle position or Torque is not part of the equation. But yes, with FLC you can indirectly adjust descent rate with the throttle, or directly by changing the commanded airspeed. In small airplanes it is somewhat rare to climb and descend in FLC. Most people use VS (or VNAV).

1 Like
14

TBM900 Hotstart for xplane - same thing, FLC is used for climb and VS for decend.

15

Also the FLC adjustment buttons are backwards. When you press UP, it should set a LOWER airspeed and DOWN should set a HIGHER airspeed. The buttons mean “nose up” and “nose down”. This way the UP/DOWN buttons work pretty much the same for VS and FLC.

16

Have you Zen’d this?

Strangely FLC descent isn’t working here either, and I do know how to use it.

Climb is fine.

17

I’ve noticed this too and assumed it was intended that way so that you can maintain airspeed while climbing. FLC for ascend, VS for decend. Can anyone confirm if the FLC should also work for decend?

18

I don’t know if it should work but I can confirm that it does work (for me anyway)…

19

Thanks - can you clarify how you are using it? Do you set the new altitude and just press FLC and the AP maintains airspeed and changes to the new altitude? Do you need to reduce the throttle as well (presumably yes)? Do you set the desired airspeed as well? I’ve not tried that - so maybe that’s what I’m missing?

20

See my first post in this thread - about half way down…

21

Got it, thanks - hadn’t realised that was your post. Thank you, will try tonight