v0.1.3 AP Problems

The Sledge

Hi,

seems there is something wrong the AP:

AP captures selected Altitude 100-200 feet off (+/-).

<snip>

Concur. This behaviour was not present in 0.12 but experienced every flight in 0.1.3
Bug introduced. Also I should mention that the altitude capture event is very abrupt, bordering on violent, which introduces some porpoising before settling at the incorrect altitude.

Martyn

This'll be fixed later today - https://community.justflight.com/topic/3387/update-change-logs-v0-1-3-released-edited-26-5-22

sbanks75

Ah good, not just me then! Posted similar in the 1.3 thread. I also had real trouble activating glide slope on final approach. Real trouble as in couldn’t activate it at all

Melon

@martyn I have noticed an issue on two flights now, when I am descending with VS and want to slow down (eg 250 -> 200 knots), the aircraft doesn't slow down but rather nose dives harder to maintain the speed it is currently doing (2000fpm -> 4000fpm, and staying at 250 knots), it feels like its confusing VS for IAS somehow.

The Sledge

@martyn

Belter.

I don't care what anyone says; I like you :)

Martyn

@melon How are you attempting to slow down? e.g. using SYNC mode to adjust the VS or just reducing thrust? I can't think of any reason for that behaviour

b3lt3r

@the-sledge I like you too :-)

Melon

@martyn Moving throttles back to near idle to maintain ~60% N2 (with DESC set on the TMS), and using SYNC mode to set VS. Previously I still had to use the speed brake a little bit to maintain 250 knot descent, otherwise it'd speed up a bit over time.

The Sledge

@b3lt3r lols I just realised why you replied :D

The Sledge

@martyn

Alt capture and hold perfect now thank you

esdigi

Downloaded v0.1.4, but still having AP problems during descent. Armed new altitude, AP sync mode and trimmed to 1500 feet/min sink. When AP sync is turned off, altitude sink rate gets back to 0. Having to descend manually.

Martyn

@esdigi Just to confirm as you don't mention it, you are selecting VS mode after selecting ALT ARM, and before using SYNC mode?

esdigi

@martyn Yes, Select and arm altitude (few thousand feet below current altitude), select VS mode, AP sync mode, set sink rate, AP sync mode off. Had been working till yesterday. Today, the sink rate is going right back to zero.

Martyn

@esdigi It worked when tested earlier today but we'll investigate

esdigi

@martyn Thanks! Its getting quite late at night so I'll try it again tomorrow.
By the way, it is one of my favourite planes right now on MSFS (even after the airliners following it).

Martyn

@esdigi I've just tested it again and it still works correctly here so can you submit a support ticket so we can investigate further? https://support.justflight.com/support/tickets/new

ankhtahr

@martyn I'm encountering a possibly related issue in descent, using version 0.1.4. So far I have only been able to reproduce it when descending by more than 1000ft from the previously held altitude.

Steps to reproduce:

Starting in ALT HOLD at 7000ft, LNAV, AP on
Set ALT SEL to 2900ft, select ALT ARM => The horn sounds (not sure if that's supposed to happen)
Status as shown by the annunciators is now: ALT HOLD (green), ALT HOLD armed (white).
Select IAS, reduce thrust to idle (TMS set to DESC mode).
About 400-500ft above the selected altitude, the aircraft will start to level off, reducing the descent rate to only about 200ft/m. IAS annunciator is still green, ALT annunciator is still white, but Airspeed starts to reduce rapidly. Adding thrust to keep airspeed at the desired value will cause the plane to keep a rate of descent of only about 50ft/m, while still indicating IAS green, ALT white.
My current workaround when this occurs: Selecting VS mode, pitching down using SYNC, the AP will capture the selected Altitude as desired.

esdigi

@martyn Tried it again today. Twice it worked perfectly. The third time it again went all haywire. At 22000feet, I set the target altitude to 16000feet and armed it, set VS mode, followed by SYNC switch (TOGGLE AFTERBURNER mapped to a switch on a keyboard), then set pitch down 1500feet/min. As soon as I pressed SYNC switch again, the vertical speed shot right up to +1500feet/min or more, then settled back down to zero. I tried this a number of times, then had to turn off the AP and hand-fly it down.
Guess I will submit a support ticket like you suggested.

Martyn

@esdigi Can you post screenshots showing the flight annunciators and glareshield before and after you have used SYNC mode to adjust the VS?

Laurens

I can confirm these autopilot problems. Yesterday I made a flight without any problems (version 0.1.4) and today the autopilot did not wanted to descent. Plane used, 146 200

The first stage of the decent went well, from 23000 ft to 15000 ft. As I was almost at 15000 ft I had to go to 3000 ft. While I was still descending (about -500) I selected 3000, Armed, set VS, SYNC on set vs -2000, sync off. Autopilot did not keep vs, came back to 0. Tried a few times to set the vs, but did not work. So I did de descent manually. Plane used 146 300