A320 THR LVR FAULT

[MD83FO]

Good morning,
how would you handle a VOR Approach
with GO AROUND with THRUST LEVER FAULT ?

[Togue]

Approach: respecting the limitations regarding NPA with OEI
GA: SE GA, leave the flaps at 1 and return for ldg. Thrust on affected engine will remain at idle for the GA.

[tubby linton]

Some Airbus are not certified for a managed NPA with OEI.

[sonicbum]

Originally Posted by tubby linton

Some Airbus are not certified for a managed NPA with OEI.

I believe you are referring to a specific limitation of the Autoflight system on some MSN to conduct NPA with one engine out, but nothing prevents you to hand fly it in FINAL APP, provided of course that all other conditions are satisfied (accuracy, temperature deviation, etc..)

[EI-PAUL]

All the new 320's can fly NPA SE approaches using AP in FINAL APP, NAV V/S or NAV FPA without limitations.
The limitation still applies for some old 320's, in this case you must check your MSN.
Instead the limitation always applies to the 319's fleet, in this case, as suggested by sonicbum, you may elect to hand-fly the approach in FINAL APP mode.
Ref:FCOM-LIM 22 10 NPA with EO

[tubby linton]

True, you could handfly the approach. All of our 320s have been modded to allow use of the autopilot, all of our 321s have the restriction.

[MD83FO]

Thanks for the interventions, my query digs more into the expected behavior of the thrust. Thrust lever resolver is out, but it seems, acording to FCOM LAYER 2 expanded, that autothrust can be used on that engine, if this is the case, i wonder what will thrust become in goaround once the flight director goes into auto thrust armed( blue).

Thanks

[tubby linton]

The thrust will remain at idle for that engine.

[Microburst2002]

The moment you lower the L/G or extend any slats flaps, thrust goes to IDLE. What I don't know is if in case of a go around, you recover the engine after cleaning.

[Goldenrivett]

Hi Microburst2002,

FCOM PRO-ABN-70 Power Plant
ENG 1(2) THR LEVER FAULT.

"For any case of thrust lever fault (TO, FLEX or between IDLE and MCT) the FADECwill command idle thrust for the approach when slats are extended (or when MN < 0.47 if associated EIU is failed). It is independant of the autothrust condition. Thrust of affected engine remains definitively at idle even for go around and the reminder of the flight."

I've tried it in the sim and thrust remained at idle even when clean.

[mcdhu]

With respect to Microburst2002's post above, it's when Conf 1 or greater that the affected engine goes to idle and stays there even on G/A. Reverse is not available. The landing gear has no vote.
Cheers
mcdhu

[FlightDetent]

You'd get it back with A.FLOOR.

[Microburst2002]

thank you golden rivett, that is a valuable information!

[sonicbum]

mcdhu,

I believe the L/G reference of MB2002 is for the A330.

[mcdhu]

Thanks Sonic.

FD you'd have to move the TL though. Because the A/Thr senses an EO condition with the TL at idle and thus no A FLOOR?

So maybe the GA technique for GA with TL FAULT should be - Both to TOGA, Full back stick to activate A FLOOR, Both to CLB Gate, Disconnect A/Thr, Rearm A/Thr, Recover. Apologise to ATC for busting Stop Alt!

Must try it in the sim!!

Please don't try this at home folks!!

Cheers,
mcdhu

[Ragazzo]

Good thinking FD, interesting subject, looking forward to the result of your experiment mcdhu

[FlightDetent]

Well, finished sim programme somewhat earlier and the instructor offered to take us for a joy ride.

Overhead at FL80, THR LVR 1 FAULT and a minute later ENG 2 FAIL (no relight). And so the story unfolds ...

[dream747]

Go with a flapless landing? You'll keep the engine with the thrust lever fault running?

[FlightDetent]

dream747 That's good thinking! No, we did not do it, closer inspection of my memory reveals, that the setup was probably different.

I do remember discussing F3 single (and idle) engine option but that never happened actually.

The OEI was only introduced on final approach. Then the pull into the red barber pole for A.floor. I have no idea why did we not capsize due Vmca, maybe we were still F1 and Vaprot > Vmca?. The TRE had the plan, I did not.
The G/A was pretty normal, but afterwards running engine stuck at TOGA, due to no TL resolver. We managed to stabilize about -400 fpm descent with full flaps out and come around for a shallow approach. Kill the thrust with Master SW (which was plan B, we mismanaged something) after touchdown.

Toys for boys, but after year and a half that's the only thing I remember from the session AND ENJOYED IT.

mcdhu I'd have to look into that, but in general my understanding is that A.floor works irrespective of A/THR (e.g. disengaged); yes there's the 40 sec disconnect proc ...
Interested in your SIM observations too!

[Lantirn]

Since it's relevant I will continue here.

It's complicated to understand what will happen from the FCOM. At least it's not crystal clear.

I am talking about THR LEVER FAULT + EIU fault at 500ft during takeoff.

2nd scenario THR LEVER DISAGREE + EIU fault at 500ft during takeoff.

Caution, I am talking only about takeoff, not during high speed and high Mach numbers.

I cannot understand if the thrust will be idle immediately after the failure due to Mach no being below 0.47, or conditions have to be satisfied to happen.

1st scenario:
As far I can explain and understand in THR LEVER FAULT plus EIU, you are at flex or toga, so FADEC normally is supposed to maintain takeoff thrust until slat retraction where it selects MCT thrust. However here slat position is already unreadable by FADEC due to EIU failure, so it should switch to approach condition due to Mach number, that is IDLE thrust (approach idle due to EIU). So practically there is nothing you can do, idle thrust is commanded. You can not delay it.

2nd scenario
THR LEVER DISAGREE plus EIU, assuming both TLA are above idle. Takeoff thrust is maintained normally until thrust reduction, at which point maximum thrust available is CLB thrust depending on the higher resolver position. After that point, it should trigger the approach condition when slats are extended. However again this is impossible due to EIU, so idle again due to low Mach number. So practically, you have idle thrust by the time you select CLB thrust in the thrust levers. It is noted in L2 as "If TLA at, or below, MCT and if the slats...". Practically here you can delay the idle selection by the FADEC.

Any corrections, suggestions?

Autothrust is out of the game due to EIU fault.
As autothrust is INOP, no alpha floor available.
What would happen in the other engine in this session can be questionable, but it depends on the scenario selected. I assume in the second scenario an engine fail could be managed with some speedbrakes and gear as long as CLB thrust is not selected on the discussed one.