JeeHell FMGS forums

Hey guys,

It is the second consecutive time that I have the following issue. After takeoff, the AC reaches only a speed of 175-180 knots during the climb. The AP disconnects several times because speed is too low. Engines have ca. 87% (CL detent). Pictures attached.

The autopilot also exceeds the selected altiude and keeps climbing.

After correcting the altiude and reaching cruise altitude, the AC accelerates and reaches the usual .778 mach.

What can be the reason for this behaviour?

You're still in SRS mode which is not normal, and should not happen. SRS should switch to CLB at ACC ALT. What values do you set in THR RED/ACC ALT in the MCDU?

Hi Jean Luc,

I never changed those values (also not during the planning of the last two flights when the problem occured).

BR, Alex

jeehell wrote: ↑Wed Mar 22, 2023 12:31 pm You're still in SRS mode which is not normal, and should not happen. SRS should switch to CLB at ACC ALT. What values do you set in THR RED/ACC ALT in the MCDU?

Do I need to enter / adjust these values at all?

No if they are correct.
When do you retard the THR LVR from TOGA/FLX to CL detent?

jeehell wrote: ↑Wed Mar 22, 2023 5:33 pm No if they are correct.
When do you retard the THR LVR from TOGA/FLX to CL detent?

When LVR CLB starts flashing on the PFD.

which airport, RWY and SID was it on?

jeehell wrote: ↑Wed Mar 22, 2023 8:13 pm which airport, RWY and SID was it on?

It was NZWN/16, ATVE1Q.

I might have found the reason. When I sat in the cockpit today in the evening, I recognized that before the last two flights when the described problem occured, I have performed the engine fire test which I practically have never done before. I tried it only once long ago with the B56 version and couldnt even start the engines after that. It sounds strange, but then today in the evening I have setup the same flight like today at noon but without performing the fire test. And everything worked fine again (see pictures attached).

Can this be connected somehow?