A320 quiz
 

Assuming you are in cruise flight, advancing thrustlever one to the TOGA detent, number two remains in climb pwr detent. Yes, engine one runs now at TOGA. What will engine two do?

a) running at TOGA as well
b) doesn't care, remains at current rpm
c) slows down to idle
d) shuts down by a protection

Engine one wont go to TOGA at all, assuming of course you are at a normal (say above FL300) cruise level! Now you tell me why...

Thrust Lvr Asym max power MCT ???

@Spearing Britney

Are you sure...?

@FlapsOne
No, but nice try..

Certain, cos at a typical cruise level CLB=MCT=TOGA! You may change the FMA but the engine output can go no higher than the CLB limit no matter if the levers are advanced to MCT or to TOGA.

Only at low levels is TOGA>MCT>CLB, they come together as you climb and meet at FL250 or thereabouts...

.....a bit like the FCOM really!!

Cheers,
mcdhu

Spearing Britney is correct, the FMA says TOGA but engine one runs at MCT/ climb thrust. Anyhow, what about engine two?

regards

FMA says MAN TOGA and flashing LVR MCT, #2 stays at thrust necessary for managed (or slected) speed as the autothrust stays armed, dependant on whether #1 achives more thrust.

@idg

Sorry, no.

Well that's what our sim does!!

o.k.

Answer a) is correct. Number two runs at the same rpm like number one does even with it's thrustlever in the climb notch.

regards

CATCHUP

Questions for you!

1. CFM or IAE or both?

2. What technical manual reference have you found?

3. Have you cross-checked the validity on a sim? Which manufacturer?

Thanks :D

@Preppy

Questions for you!

1. CFM or IAE or both?

2. What technical manual reference have you found?

3. Have you cross-checked the validity on a sim? Which manufacturer?

1. Both, types flown and observed A319/320/321
2. Didn't look for that. Found out bei chance.
3. No, I didn't.

regards

Yeah but its not really TOGA is it?

Answer e) runs at clb limit

As bad as the JAA questions! I only make the point because it is significant at lower levels , you wont get toga out of number 2 by putting number 1 to toga below FL245 ish - the detent is always the limit.

@Spearing Britney

That's what the book of a large bus-airline says:

The pilot can always get MAX TO thrust by pushing the thrust lever all the way forward.

regards

Hi everyone, good question and here's a contradictory cut & paste from the A320 FCOM;

1. If one or both thrust levers are beyond the MCT detent, the engine instrument display shows TOGA.

OK no arguments here.

2. If the thrust levers are not aligned, an asymmetric message (ASYM or LVR ASYM) appears on the FMA. If so, each engine is limited to its appropriate TLA. This allows the use of autothrust to continue if one engine has to have its maximum RPM limited for some operational reasons such as excessive vibration.

Maybe idg was right!

3. The pilot arms A/THR : in flight ... while A/THR being active (A/THR white on FMA), the pilot sets (one) thrust lever ...above the MCT detent.

Or maybe idg (or his sim) is wrong (A/THR armed not active)

4. The pilot can always get MAX TO thrust by pushing the thrust lever all the way forward.

A translation mistake? ie should be levers (plural)

Maybe I've raised more questions than answers????

mcdude

@mcdude

Try it out!

I did and it worked like I said.

NO ASYMMETRY WARNING, cause it's not an ATHR mode!

regards

FCOM 1.22.30

LVR ASYM Amber

One thrust lever is in CL or MCT/FLX detent, and the other one is not in this detent.

-----------------------------------------------------------------

So that's a lie then, is it?

It may well be out of (above) the ATHR range, but the system is still surely telling you that there's something wrong with one of the levers that it can't do anything about. Therefore it throws up the FMA inviting your intervention.

Still think MCT is the best you'll get out of the motor, irrespective of what the FMA says.

I would like to see some reference for answer a) to be totally correct.

Catchup

Just tested your theory in a IAE A320 simulator (at FL120) - you are correct!

Preppy

Fine!

Like I said, it's not a theory I've observed it in real.

regards