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-   -   APU inop risks (https://www.pprune.org/tech-log/663856-apu-inop-risks.html)

unobtanium 28th January 2025 03:51

APU inop risks
 
with recent events around the world, and noticing the increase in inop APU's around the network, should there be a push back agaist company, and start rejecting aircraft's for having inop APU's flying around the country for week's on end?

i imagine capt sully's story will end very differently if his apu was on MEL.


AQIS Boigu 28th January 2025 04:36

A bit hard to push back as a captain if the MEL permits it - go figure, 240 ETDO doesn’t even require an APU

gordonfvckingramsay 28th January 2025 09:56


Originally Posted by AQIS Boigu (Post 11815557)
A bit hard to push back as a captain if the MEL permits it - go figure, 240 ETDO doesn’t even require an APU

As I’m sure you’re aware, an MEL simply dictates what defects you may dispatch with, not what you must dispatch with. Furthermore any preamble to an MEL is very clear in what authority a Captain possesses regarding his or her right to request any defect be rectified. Remember, your company will not back you up if you accept a defect and a subsequent problem occurs which is exacerbated by said defect. Their position will be ‘they didn’t have to accept it’.

Pilots should always be pushing back against practices that reduce safety in the interest of profit.

Servo 28th January 2025 11:07

We had a flight from Perth to Hobart, well into the bight.

Inop APU. No thanks. Swapped the aircraft. Was not taking an aircraft with an Inop APU down that way.

BinChook 28th January 2025 11:09

Nothing more enjoyable then rocking up to Melbourne on a 40 degree day with no APU, shutting down the engines after GPU plugged in and the Swissport bloke on the ground tells you “sorry there’s no qualified stair pushers so it’ll be a 10 minute wait before we can open the door”

AQIS Boigu 28th January 2025 11:54


Originally Posted by gordonfvckingramsay (Post 11815699)
As I’m sure you’re aware, an MEL simply dictates what defects you may dispatch with, not what you must dispatch with. Furthermore any preamble to an MEL is very clear in what authority a Captain possesses regarding his or her right to request any defect be rectified. Remember, your company will not back you up if you accept a defect and a subsequent problem occurs which is exacerbated by said defect. Their position will be ‘they didn’t have to accept it’.

Pilots should always be pushing back against practices that reduce safety in the interest of profit.


I am aware of that - so will you dispatch a 787 or a 330 safely without APU on a Transpac or will you insist on an aircraft swap (with an extensive delay)?

Australopithecus 28th January 2025 12:54

An aircraft with a RAT is a different kettle of fish to an obsolete aircraft without one. That said: perhaps*

*I have been…difficult for 40 years as a captain and no one has ever argued with me, In that time I have been confronted with NO generators twice** and am reluctant to explore the attendant complications again. Your curiosity and acquiescence may eventually provide you with other insights.

**including once, for a time, on a 330

JW55 28th January 2025 13:02

Ha ! APU inop, that's NOTHING compared to a day in the life of a Network pIlot. They are running around with Packs out, bleeds MEL'ed for days (no APU bleed airborne) high engine vibes, fuel leaks, FMC's inop, HYD problems, GPS no RAIM for over a year now, you name it. QF couldn't care less.

PENKO 28th January 2025 13:53


Originally Posted by gordonfvckingramsay (Post 11815699)
Remember, your company will not back you up if you accept a defect and a subsequent problem occurs which is exacerbated by said defect. Their position will be ‘they didn’t have to accept it’..

I’m not sure what company you work for but a half decent company has no choice but to back you up if you make a sensible professional decision regarding an MEL. Accepting an MEL is just one of the hundreds of discretionary decision you make in a month, that’s what you get paid a professional salary for.

Now of course, if you think your company is bending the rules, then we are playing a different ballgame all together…

No Idea Either 28th January 2025 21:52


Originally Posted by JW55 (Post 11815818)
Ha ! APU inop, that's NOTHING compared to a day in the life of a Network pIlot. They are running around with Packs out, bleeds MEL'ed for days (no APU bleed airborne) high engine vibes, fuel leaks, FMC's inop, HYD problems, GPS no RAIM for over a year now, you name it. QF couldn't care less.

See post #3…………………don’t take them.

gordonfvckingramsay 28th January 2025 21:54

It doesn’t really matter who I work for. Suffice to say it’s concerning that any Australian RPT jet operator is still entrenched in the good ol’ GA mantra of ‘it says you can go so you should’. This also goes beyond just APUs, how many deferred items are airborne as we speak, and how many of those are occurring simply because airlines prefer to prioritise profit over maintenance? The company I work for is known for not-so gently coercing the Captain into accepting a defect just because the MEL suggests you can.

gordonfvckingramsay 28th January 2025 22:25


Originally Posted by JW55 (Post 11815818)
Ha ! APU inop, that's NOTHING compared to a day in the life of a Network pIlot. They are running around with Packs out, bleeds MEL'ed for days (no APU bleed airborne) high engine vibes, fuel leaks, FMC's inop, HYD problems, GPS no RAIM for over a year now, you name it. QF couldn't care less.

And that is the beauty of holding BUs at arms length. If it all turns to custard one day, all the parent company has to do is get corporate comms on it and claim that ‘it’s a subsidiary who mismanaged to operation and we didn’t know’. et voila, in the minds of the public, the perfect safety record persists and business as usual.

unobtanium 28th January 2025 22:53


Originally Posted by JW55 (Post 11815818)
Ha ! APU inop, that's NOTHING compared to a day in the life of a Network pIlot. They are running around with Packs out, bleeds MEL'ed for days (no APU bleed airborne) high engine vibes, fuel leaks, FMC's inop, HYD problems, GPS no RAIM for over a year now, you name it. QF couldn't care less.

endof the day your responsible for you're aircrafts not network or qantas. at the court hearings question one is why did you accept that bucket of bin chicken sh1t

Zumba in the street 28th January 2025 23:29


Originally Posted by gordonfvckingramsay (Post 11816131)
It doesn’t really matter who I work for. Suffice to say it’s concerning that any Australian RPT jet operator is still entrenched in the good ol’ GA mantra of ‘it says you can go so you should’. This also goes beyond just APUs, how many deferred items are airborne as we speak, and how many of those are occurring simply because airlines prefer to prioritise profit over maintenance? The company I work for is known for not-so gently coercing the Captain into accepting a defect just because the MEL suggests you can.

Ahhh the old Accountants sniffing around the DDG at 2am. Ahh those were the days.

Icarus2001 28th January 2025 23:37

I see some of the items in the MEL as a way to get the aircraft home to a maintenance base, not a way to fly it for two weeks with a US item. Notwithstanding the ten or thirty day restrictions.

Hey_pahlot 28th January 2025 23:46


Originally Posted by JW55 (Post 11815818)
GPS no RAIM for over a year

I believe that's with all Fokkers, not just the WA red rats

blubak 29th January 2025 06:23


Originally Posted by JW55 (Post 11815818)
Ha ! APU inop, that's NOTHING compared to a day in the life of a Network pIlot. They are running around with Packs out, bleeds MEL'ed for days (no APU bleed airborne) high engine vibes, fuel leaks, FMC's inop, HYD problems, GPS no RAIM for over a year now, you name it. QF couldn't care less.

Well i hope that every pilot is researching every current MEL on every aircraft they enter the cockpit on.
It doesnt matter how long it takes, if it causes a delay that is not your problem.
The chief pilot or any other management stoog will not be sitting next to you at 30,000 feet when you need to make a decision because of an equipment failure due to their dont care cost cutting measures.

TimmyTee 29th January 2025 08:45

Spare a thought for the FOs who may feel that it’s not acceptable, but due to it being “the Captain’s ship” would find it tough to speak up and effectively over-rule, and don’t have that defence in stepping off..

ScepticalOptomist 29th January 2025 08:52


Originally Posted by TimmyTee (Post 11816338)
Spare a thought for the FOs who may feel that it’s not acceptable, but due to it being “the Captain’s ship” would find it tough to speak up and effectively over-rule, and don’t have that defence in stepping off..

First question I ask my FOs when dealing with a serious MEL - any reason you wouldn’t take it?

PENKO 29th January 2025 09:07

The question in the OP is actually quite interesting: what is the risk of flying around without an APU and how does that correlate with the latest spat of incidents.

Was the APU a factor in any of the recent incidents to such an extent that the whole MEL safety assessment should be reconsidered? Contrary to the OP I don’t think the APU was a deciding factor in any recent incidents. Even in Sully’s case.

So, do we need to ask the manufacturer, legislator, regulator, airlines and pilots to reconsider the APU rectification interval in the MEL? Is there an emerging case for this? I doubt it.

gordonfvckingramsay 29th January 2025 09:34


Originally Posted by PENKO (Post 11816351)
Contrary to the OP I don’t think the APU was a deciding factor in any recent incidents. Even in Sully’s case.

Because it was switched on and it worked.

gordonfvckingramsay 29th January 2025 09:37

The larger, underlying question most of us have latched onto is the overuse of MELs to keep an under maintained fleet operating.

Wing Root 29th January 2025 10:12


Originally Posted by gordonfvckingramsay (Post 11816368)
Because it was switched on and it worked.

Indeed

The captain's swift and thoughtful action in immediately activating the APU also contributed to the successful ditching because the APU allowed the fly-by-wire system to remain in Normal Law. Without the APU, the aircraft would not have descended with the flight envelope and stall protections that Normal Law afforded. These protec-tions proved especially crucial because the aircraft entered al-pha-protection during the final approach, and the system may have kept the plane above the stall speed during the last 150 feet of the descent.

Got any ideas?

PENKO 29th January 2025 11:39

All kudos to Sully and his colleague by the way. Without the APU the aircraft would have flown in direct law, (just like a 737). Airbus aircraft land in direct law quite regularly after some in-flight computer failure so I’m sure Sully would have been able to ditch without a working APU. The argument that the accident report tries to make is a bit of a circle reduction. Yes the APU allowed normal law to protect the aircraft from stalling, but without the APU, Sully would have flown the aircraft in direct law, respecting the stall warning like in a conventional aircraft. He could have arguable made a more controlled ditching in stead of (unknowingly!) pulling so far back fully on the side stick that the computers had to take over to safe the aircraft from a stall over the Hudson.

The only area where the APU might have been critical is if an engine in-flight restart would have been possible. Which was not.

So more to the point, did the FAA change any MMEL after this incident regarding serviceable APU? Was there a need?

tdracer 29th January 2025 18:21


Originally Posted by gordonfvckingramsay (Post 11816369)
The larger, underlying question most of us have latched onto is the overuse of MELs to keep an under maintained fleet operating.

Everything on the MEL has a time limit associated with it (3 days and 10 days being the most common) - in most cases it can be extended, but just once (so figure 6 days and 20 days), at which time the aircraft is effectively AOG until the defect is fixed.
The intent - as Icarus noted - is that, during that time period, the aircraft will overnight at a maintenance base where the defect can be corrected.

gordonfvckingramsay 29th January 2025 20:17


Originally Posted by tdracer (Post 11816603)
Everything on the MEL has a time limit associated with it (3 days and 10 days being the most common) - in most cases it can be extended, but just once (so figure 6 days and 20 days), at which time the aircraft is effectively AOG until the defect is fixed.
The intent - as Icarus noted - is that, during that time period, the aircraft will overnight at a maintenance base where the defect can be corrected.

Thanks for the refresher…I am intimately familiar with how an MEL works. The intent may be as you say but the reality is far less purist. The sheer number of aircraft carrying deferred items departing SYD, MEL, BNE etc every morning that also left yesterday morning and the morning before that, and the morning before that is higher now than ever before. As I said, under maintained aircraft being under maintained out of a deference to profit.

maverick22 29th January 2025 22:14

The new uniform should fix things though…

cLeArIcE 29th January 2025 23:01


Originally Posted by TimmyTee (Post 11816338)
Spare a thought for the FOs who may feel that it’s not acceptable, but due to it being “the Captain’s ship” would find it tough to speak up and effectively over-rule, and don’t have that defence in stepping off..

Yeah sorry I don't buy into that. Part of this job is standing up for yourself and having some balls to say no sometimes.
I have politely expressed concern at multiple MELs affecting different systems that a captain was happy to accept. Told him I respected his decision as the PIC but I wouldn't be joining him.
Its not something I'd ever do lightly. But very occasionally, it is required. It's not nice nor is it easy but that's why you are there.

Lookleft 30th January 2025 03:47

Like everything else in airlines whenever there is a limit for something e.g. MEL,FD, FOD, there is now a target. whatever the intent was for a limitation has long been discarded and a binary choice has now been presented. That choice is "are you legal, yes or no?". Too many PIC's have been kowtowed into following the company line but if they understood their legal responsibilities then they would realise that standing firm will not get you fired. As clearice stated an F/O has to also stand firm if they believe the situation is compromised. The only way you get to be a captain that stands up to the company is to be an F/O that is prepared to do the same.

neville_nobody 30th January 2025 05:59


Originally Posted by Lookleft (Post 11816872)
Like everything else in airlines whenever there is a limit for something e.g. MEL,FD, FOD, there is now a target. whatever the intent was for a limitation has long been discarded and a binary choice has now been presented. That choice is "are you legal, yes or no?". Too many PIC's have been kowtowed into following the company line but if they understood their legal responsibilities then they would realise that standing firm will not get you fired. As clearice stated an F/O has to also stand firm if they believe the situation is compromised. The only way you get to be a captain that stands up to the company is to be an F/O that is prepared to do the same.

I don’t hold a lot of faith in the ‘legal’ argument as so-called aviation law and what we think is legal can be weak in court.

It would be interesting to actually see what position we are in legally if we refused a MEL then got fired or sued how all that stacks up. The problem is Pilots aren’t subject matter experts so on what basis are we saying something is unsafe? How are you going to argue against Company expert witnesses endorsing the MEL?

I know of too many examples of what was actually safe or the correct decision wasn’t legally ok.

Icarus2001 30th January 2025 06:07


It would be interesting to actually see what position we are in legally if we refused a MEL then got fired or sued how all that stacks up.
There is a line in the pre-amble that gives the PIC authority as to accept an MEL item or not. End of discussion.

gordonfvckingramsay 30th January 2025 06:51


Originally Posted by Icarus2001 (Post 11816931)
There is a line in the pre-amble that gives the PIC authority as to accept an MEL item or not. End of discussion.

Absolutely correct! Also, we are SMEs on our aircraft type, the endorsement process sees to that.

neville_nobody 30th January 2025 09:58


Originally Posted by Icarus2001 (Post 11816931)
There is a line in the pre-amble that gives the PIC authority as to accept an MEL item or not. End of discussion.

Sure I am aware of that but where does that stand legally though if it all gets nasty? Those in the industry take the preamble as being the end of the matter, the law may not see it that way.

FlightDetent 30th January 2025 13:19


Originally Posted by PENKO (Post 11816420)
All kudos to Sully and his colleague by the way. Without the APU the aircraft would have flown in direct law, (just like a 737).

[--- cut out ---]

where the APU might have been critical is if an engine in-flight restart would have been possible. Which was not.

So more to the point, did the FAA change any MMEL after this incident regarding serviceable APU? Was there a need?

This will be one of the most under-appreciated posts of 2025.

hotnhigh 30th January 2025 19:07

The bigger question is where is the regulator in all of this?
Clearly they are satisfied with the health and maintenance of the fleets across airlines, cough cough, across Australia.
i mean why were some of the Ansett fleet grounded again in history gone past?
The sh);t is hitting the fan and there appears to be silence from them.

cLeArIcE 31st January 2025 00:09


Originally Posted by hotnhigh (Post 11817607)
The bigger question is where is the regulator in all of this?

Let's be honest, apart from some CASA tokenism wielding of the big stick at small issues, the Q group is its own self regulator and CASA does what it's told. You only have to look at the fatigue rules to see that.

Icarus2001 31st January 2025 01:14


Those in the industry take the preamble as being the end of the matter, the law may not see it that way
All of the relevant regulations, the act, and company operations manuals give the PIC final authority on almost everything. They have to as the PIC has final responsibilty for the safety of the flight. With the responsibilty comes the authority.

gordonfvckingramsay 31st January 2025 05:32


Originally Posted by neville_nobody (Post 11817123)
Sure I am aware of that but where does that stand legally though if it all gets nasty? Those in the industry take the preamble as being the end of the matter, the law may not see it that way.

The company document suite, in its entirety is legally binding. They will hang you with any and all of the applicable document if you ever fvck up. Neither they nor you and I can cherry pick. The preamble is sacrosanct. We shouldn’t be accepting any MEL other than to return to a maintenance base, even then you’d need to be able to explain to a judge why you chose to accept the MEL if you were ever unfortunate enough to be fronting a board of inquiry.

Just for sh!ts-n-gigs, count how many times you hear the word ‘safety’ the next time you pax anywhere. You would swear they believed it.

Newhairdo 31st January 2025 05:43


Originally Posted by gordonfvckingramsay (Post 11817946)
The company document suite, in its entirety is legally binding. They will hang you with any and all of the applicable document if you ever fvck up. Neither they nor you and I can cherry pick. The preamble is sacrosanct. We shouldn’t be accepting any MEL other than to return to a maintenance base, even then you’d need to be able to explain to a judge why you chose to accept the MEL if you were ever unfortunate enough to be fronting a board of inquiry.

Just for sh!ts-n-gigs, count how many times you hear the word ‘safety’ the next time you pax anywhere. You would swear they believed it.

Agreed.
And if the Captain says we are not going, then that’s it. Game over. End of story.

Jester64 31st January 2025 07:29

Flown buses with the APU completely removed because I could. Was it unsafe? No. Was it legal? Yes. Was it efficient? Yes. Would I be having ****ty day IF I lost both engines. Yes. Did that bother me? No. Did I get the job done and was the airline / pax happy? Yes. Did I have faith that the appropriate risk assessment was performed by the manufacture when constructing the MMEL? Yes.


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