Is A330 More ETOPS Capable Than B 767???

[AeroTech]

Hi,

First this is not Airbus versus Boeing...
We have a discussion in other forum about the APU automatic shutdown (in flight) in the recent APU's compared to the old, and this lead us to some stuffs that I didn't understand. Briefly, are these statements true:

1-In A330 you can do an ETOPS (180 minutes) flight if the APU is broken, but you still need to have the fire extinguishing capability.
2-If the APU is inop in B 767, ETOPS is limited to 120 minutes.

Are these 2 statements true? If yes, why?
If the first statement is true, why the fire extinguishing must be available and operative with APU inop for a full ETOPS flight (180 minutes)???

Feedback appreciated.
Best regards

[kenparry]

I have doubts about your point No. 2. It's some years since I was involved, but my recollection of B767 ETOPS uder the rules of the UK CAA is that the APU was required for all ETOPS so that a spare alternator was available.

Possibly your FAA rules are not the same?

[ironbutt57]

Boeing MMEL....apu for etops beyond 120 mins on 767

[Backtrack]

Hi Aero Tech,
I'm currently flying 767s for a UK based JAR-OPS 1 operator (I suspect the same as kenparry used to work for) and The MEL allows ETOPS up to 138 mins provided both eng driven genis(IDGs) are working & the Hydraulic Motor Geni (HMG) is verified to operate normally.
As to why, I think it's down to what you have left if both IDGs should fail & the simple answer is not a lot!! Lose 1 IDG & not much happens; there's obviously some load shedding (galleys, pax convenience items, the odd hydraulic pump etc), but the working IDG will still provide a full set of flight deck instruments.
The HMG is powered by the centre hydraulics & will start automatically- hopefully! - when both L & R main AC busses are unpowered. The only busses that are now powered are:
AC
1. L & R Inst Transfer Busses (powering items considered necessary for ETOPS),
2. Capt's Flt Inst Transfer Bus,
3. AC Standby Bus.
DC
1. Hot Batt Bus,
2. Batt Bus,
3. DC Standby Bus.
This basically means that the Capt has a few, essential flight inst & the co-pilot has none!
Have no knowledge of the A330, but if your claim is correct maybe the equivalent of the HMG is cleverer & provides a greater level of power.
Hope this helps.

[AeroTech]

Hi,

Thank you for your posts.
I am not claiming that A330 is capable of full ETOPS (180 minutes) even if the APU is inoperative, I am wondering if it is true. If the answer is affirmative, WHY the A330 have such capability even if the APU generator is inop?
It will be nice and helpful if someone can check and post this information from an official MEL. I don't have access to the official manuals:I get some information from the net, and I don't know if these information are updated and accurate (it says that the A330 cannot perform ETOPS flight beyond 120 if the APU is inop). I think the RAT in A330 can provide hydraulic and electric power (not fitted with HDG:hydraulic driven generator as in B767) and also it is not fitted with BUG (back up generator like in B 777).

Feedback appreciated. Thank you.
Best regards

[SMOC]

A330 APU (MEL 49-11-01)

May be inoperative provided:

1) No operation or procedure is predicated on APU use, and

2) The MASTER SW pb sw is selected Off.

[Consider 24-22-01 (AC MAIN)],

Airbus's typical way of repeating itself as this is a procedure (Single GEN) predicated on APU use as they have already said in point 1.

and

[Consider 36-11-01 ETOPS (BLEED)]

Again a procedure which is predicated on APU use. (Single BLEED)
You may do one ETOPS flight with one bleed, but still need the APU.

There is NO ETOPS limit for the A330 in the entire chapter of the MEL 49-XX-XX, also the only ETOPS restrictions in the MEL under electrical 24-XX-XX are, Dispatch is not allowed with AC BUS 2 (ALTN function) inoperative and the IDG oil circuit must be checked prior to each flight.

777 (MEL 49-11-1 Auxiliary Power Unit)

APU may be inoperative provided:

a) Other procedures do not require its use,

and

[b) Flight is operated within 180 MIN of a suitable airport.