Autobrake and Reverse thrust problem while landing

[malfoy123 0]

Been flying this bird for a while, and found this problem happens to many around 80% of my landings.

Here's what I do on a manual landing with A/T on in SPD mode, A/P disengaged:

1.On final, I arm the spoiler and set Autobrake to 1 or 2;

2.Around,30 ft RA, I move the throttle lever on my Logitech Extreme 3 to idle.

3.Immediately after touch down, I press the F1 key then F2 key(1 or 2 hits only) on keyboard to engage a idle reverse. (I press F1 to ensure the thrust lever is idle, then press F2 for a idle reverse since the runway is usually long enough.

Then here's the problem:

When I pressed the F2 key to engage the reverse, I can see a yellow REV indication then changed to green on the EICAS, meaning the engine nacelle is IN TRANSIT -> IN REVERSE POSITION

However, only after 1 or 2 seconds, the EICAS Rev indication change to Yellow then number (thrust limit)! Which means the reverse thrust is disengaging ! I did not press any button or move lever on my joystick. And sometimes the autobrake automatically disengage it self and moved to Disarm position too and i did not apply any brake via keyboard/joystick. (the airplane is still around 100+kts )

 

Is anyone having the same problem? :ph34r:

 

 

 

 

[Don t moderate me this way 882]

A detailled description, thanks!

 

Have you set up your hardware controls properly (a small null zone for each axis - thrust/speedbrake) and re-calibrated (either via your OS control panel or via the FSX options)?

[777simmer 117]

I think Olli is right.

 

Initially all seems to work right.

But then since Reverse thrust selection disengages the AT things go wrong.

It looks like your thrust levers are not giving you idle thrust even you have positioned them all the way back.

 

Try recalibrating them.

 

Do you use FSUIPC?

Set idle thrust at just a tiny little bit before your TL is all the way back.

This creates a larger idle thrust area

 

or if you use the FSX interface, set a larger dead zon like Olli said.

 

 

Also, I I have setup my throttles to override the AT when in HOLD only.

 

With that, I set my thrust levers at idle at top of descend.

Why wait untill 30ft?

It could be that you are moving your TL to idle too late.

If you do anything with the thrust levers during the flare phase, then the AT will disconnect.

You have not mentioned an AT disconnect...but this could also be the cause.

[malfoy123 0]

 

 

Have you set up your hardware controls properly (a small null zone for each axis - thrust/speedbrake) and re-calibrated (either via your OS control panel or via the FSX options)?

Set idle thrust at just a tiny little bit before your TL is all the way back.
This creates a larger idle thrust area

or if you use the FSX interface, set a larger dead zon like Olli said.

I didn't setup calibration in FSUIPC,

In 737NGX, I don't have this problem.

I tried adding up some null zone in the Thrust Axis, but that results in an increase in my idle N1, the the problem remains.

One thought is maybe the problem is caused by the remaining progress of thrust reduction during landing:

When I engage the reverse, I still see the N1 is decreasing to its idle power(25%->23%), then the reverse gets disengaged automatically.

If I wait until the N1 stable at idle power, then engage reverse, no problem at all!

 

:blink:

 

 

With that, I set my thrust levers at idle at top of descend.
Why wait untill 30ft?

Good point!

 

Thanks guys!

[sosuflyer 30]

I've been having this same problem with the reverse thrust, but not with the auto brakes.

The only way I can get reverse thrust to activate is to hold down f2 until the nose wheel touches down, or wait until the nose touches to press f2.

In the ngx, I can hit f1 to ensure idle, then hit f2 right after the mains are down and get idle reverse, or hold f2 for stronger reverse.

This procedure in the 777 accomplishes nothing unless the nose is down too. It says the reverses deploy but then stow right back.

I just hadn't mentioned it till now cause it's not a show stopper

[Don t moderate me this way 882]

(...)When I engage the reverse, I still see the N1 is decreasing to its idle power(25%->23%), then the reverse gets disengaged automatically.

If I wait until the N1 stable at idle power, then engage reverse, no problem at all!

 

(...)

 

 

Still seems to me like a calibration issue (above-idle thrust with lever in idle position).

[777simmer 117]

I think so too.

 

Why dont you unplug your throttle and fly (once) with keyboard only!?

[blocks_off 5]

I've been having this same problem with the reverse thrust, but not with the auto brakes.

The only way I can get reverse thrust to activate is to hold down f2 until the nose wheel touches down, or wait until the nose touches to press f2.

In the ngx, I can hit f1 to ensure idle, then hit f2 right after the mains are down and get idle reverse, or hold f2 for stronger reverse.

This procedure in the 777 accomplishes nothing unless the nose is down too. It says the reverses deploy but then stow right back.

I just hadn't mentioned it till now cause it's not a show stopper

Hi, yes similar for me and also http://forum.avsim.net/topic/423125-question-about-reverse-thrust-ground-spoilers/#entry2822443

Thanks

[hopskip 253]

I think so too.

 

Why dont you unplug your throttle and fly (once) with keyboard only!?

 

No need to unplug. Pressing Ctrl+K disables any external inputs and sets the Sim to accept Control from the Keyboard only (Ctrl from the K only)

[sosuflyer 30]

Hopefully PMDG has already looked into this to see if it is an issue for sp1

[malfoy123 0]

According to http://forum.avsim.net/topic/423125-question-about-reverse-thrust-ground-spoilers/#entry2828524

 

PMDG's response said this issue will be fixed in SP1.

 

So..Yay!

[Lerbech 0]

I have exactly the same problem and have tried everything. It works in most cases but especially under bad weather condition reverse trust and autobreake fail. Plbne continue with 150+kts. One example is Tokyo, RJAA 081405Z, were I fail several times, but under good weather conditions reverse trust and auto breake work well. I was suspecting this to be the rod cause. But I think we have to wait for the sp1 to get this fixed.

 

Anyway: T7 is a great plane to fly.

 

Jan

[MAXM958 2]

I have exactly the same problem and have tried everything. It works in most cases but especially under bad weather condition reverse trust and autobreake fail. Plbne continue with 150+kts. One example is Tokyo, RJAA 081405Z, were I fail several times, but under good weather conditions reverse trust and auto breake work well. I was suspecting this to be the rod cause. But I think we have to wait for the sp1 to get this fixed.

 

Anyway: T7 is a great plane to fly.

 

Jan

I agree with you !

 

Thanks for sharing with us.

 

Marco Aurélio

[Wanthuyr Filho 83]

What do you think about Autobrake 1? More effective than should be?