Re: ETOPS question on Aer Lingus A330

Date:         29 Nov 97 03:24:28 
From:         Seth Dillon <bdillon1@mindspring.com>
Organization: MindSpring Enterprises
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Karl Swartz wrote:
> I thought the MEL included equipment that would be required for, say,
> 180 minutes, but could be inop for 120 minutes ETOPS.

I have been mulling this over for a while and I can not think of
anything that would allow this.  ETOPS status (for a specific airplane)
is either yes or no.  The only possibility that comes to mind might be
the substitution of a 180 min cargo fire bottle with a 120 min bottle (I
am not even sure such an animal exists).

> Now why would any airline be crazy enough to do that?!  Oh, I forgot
> you work for the engine-type-of-the-month club, er, Delta.  :-)

Hey, it is good job security for the training department. LOL

> >... they may be restricted to 60, 90, or 120 until there is enough
> >reliability data assembled to satisfy the carriers NAA that 180 is
> >justified.
>
> The reliability data is specific to the airframe/engine combo, not
> the carrier.

Not entirely correct, as I understand the system.  Each carrier must
maintain a diversion rate and/or IFSD rate ( I forget the exact numbers)
below an established limit for each ETOPS airframe/engine combination in
the fleet.  For example just because carrier A's IFSD rate exceeds the
limit for the 767/PW4000 aircraft it operates it does not mean all
767/PW4000 aircraft in the world are now downgraded.  Also a carrier
operating, for example, A310/JT9D-7R4 may lose its ETOPS authority on
that aircraft due to an unacceptable IFSD/Diversion rate while
maintaining ETOPS authority on its 767/PW4000 fleet.

>  The 767-300 / CF6-80C2 has long been certified
> to 180-minute ETOPS, so an airline already flying other types under
> ETOPS rules shouldn't have any problem getting ETOPS certification
> for the new combo.

True, although that is really the call of the carriers PMI.  Some may
have some heartburn over granting the full 180 if the carrier had no
experience with the CF6-80 at all.

-Seth