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Engaging FLCH on the ground

Started by Hardy Heinlin, Mon, 11 Apr 2016 11:47

Hardy Heinlin

Last time you checked FLCH did engage. Just the A/T didn't engage.

Britjet

Yes, you're right. It did. Hmmmm.
Recheck required..
Peter.

Hardy Heinlin

Have you been in a different* 744 sim? Are the 744 sims all identical, equipment-wise?


* English lesson: "different" or "another"?

Britjet

One of the 4 sims is usually configured as a GE for third-party work. The others are standard BA config.
I will check back and see which one I was using last time. I try to avoid testing on the GE sim though..
Edit - just checked. They were both BA sims.
It is probably something I did - I am working like a one-armed paper-hanger when I do this, trying to keep the aircraft right way up with a beginner flying it, answering questions about one thing while talking about another, trying a test agenda while allowing them free rein - it's a madhouse! Not an ideal test situation :-(
Peter

Ps edit - either...:-)

John H Watson

QuoteFLCH didn't engage?

Do you mean THR didn't appear on the FMA in the A/T slot? Or FLCH SPD didn't appear in the A/P vertical slot either?

Britjet

Nothing happened at all. I will retest it when I next get chance.
Peter.

Will

I'm sure it would be an unacceptable violation of the students' privacy, but were it not to be so, then you could stick a GoPro digital camera to the ceiling and record the session. Alas...
Will /Chicago /USA

John H Watson

QuoteNothing happened at all. I will retest it when I next get chance.

Much appreciated. This doesn't quite align with my real aircraft tests. FLCH was shown on the FMA and the pitch bar responded (but the engines weren't running).

Britjet

Tested again today on BA sim. As per my originsl post.
Aircraft set up on runway for departure, with 6000 in ALTSEL. Flaps 20.
FLCH SPD on vertical mode. No autothrottle engagement.
Peter.

Will

Thanks, Peter. That's starting to sound pretty conclusive.

Will /Chicago /USA

John H Watson

Re FLCH, you didn't happen to notice the pitch bar did you, Peter?

Hardy Heinlin

#31
As usual, it most likely commanded maximum nose down in order to increase the airspeed above 30 knots :-)


(It also does so when engaging V/S and setting -8000 fpm. I just noticed in version 10.0.9, when on the ground, the FD bar won't go below 0° if the new option "IDLE on non-autoland" is selected. This is an unwanted side effect. But it's just cosmetics.)

emerydc8

QuoteI just noticed in version 10.0.9, when on the ground, the FD bar won't go below 0° if the new option "IDLE on non-autoland" is selected.

Not even cosmetic if you don't use that option. Thanks, Hardy.

Jon

Britjet

The pitch bar - sorry - yes, it moved to zero pitch.
Peter.

Hardy Heinlin

Not to -15°? Are you sure? Surely it moved down from the TOGA +15° position; perhaps it moved further down below the horizon? I think I once saw -15° on a Qantas aircraft :-)


|-|ardy

Britjet


John H Watson

That's a worry... That's one of the methods we used to check the A/P after we replaced an FCC. Engaging V/S (from TOGA) V/S = 0000 (synching with current V/S)...  pitch bar goes to zero.  V/S down, pitch bar down. V/S up, pitch bar up. With hydraulics engaged, the column moved in the direction of the bar.

Hardy Heinlin

Maybe FLCH is different to V/S regarding the ground test? Peter tested FLCH, not V/S.

Britjet

I'll try VS next time I'm in.
Peter.

John H Watson

QuoteMaybe FLCH is different to V/S regarding the ground test? Peter tested FLCH, not V/S.

My mistake.. I thought the topic had switched to V/S.

As per the video I posted earlier (on a real aircraft), the bar does go down with FLCH on my old airline. This applies whether the MCP altitude is above or below the aircraft altitude (with airspeed zero and engines off)