Compressor Stall:
I have been in Qantas for nearly two decades, have been on the line for the entire time and have regularly operated Trans-Pacific and very long range flights. You know how many times I have been in the situation that we are all debating here on this thread?
None! Nada! Zilch! Zippo!
I can, however, relate a tale from real-life experience to balance this discussion about always having an alternate.
NZ regulations required us to always have an alternate from top of descent. So to digress here briefly, if CASA were aghast at the QF policy, they could easily introduce a similar regulation if they wished. They haven't.
Anyway, I once flew from Sydney to Auckland (yep back when QF trans-Tasman flights were actually flown by Qantas pilots) that departed Sydney about 9pm and arrived in Auckland about 2am local time. The alternate airports in NZ for the aircraft type were Wellington and Christchurch.
The TAFs for the flight were Auckland - CAVOK for the entire period with no deteriorations at all; Wellington - fog for our ETA; and Christchurch - fog for our ETA. For the return scenario, Sydney would close due curfew half-way across, which left Brisbane and Melbourne (with a very strong jet stream to negotiate before landing).
The flight plan had us arriving in Auckland with sufficient fuel to divert from TOD to Nadi (which must have required less fuel than diverting to Brisbane or Melbourne from TOD). When we were approaching the west coast of NZ, we could see the lights of Auckland from 200 miles out, yet because of the NZ regs we landed with over 20 tonnes of fuel (which was astronomical for a 767). Could you imagine the cost of fuel carriage if this was multiplied for every single sector that we operate?
A second story:
When the cost of fuel was very high, our flight planning section was looking to minimize fuel carriage and Batam, about 15 miles away from Singapore Changi was approved for use as an alternate.
When we arrived at flight planning at Heathrow, Singapore had TEMPO TS for about an hour either side of our arrival time. Batam, however, was a single-line forecast and so we were given diversion fuel to Batam (5/8s of f*** all) rather than TEMPO holding fuel. That day we had the luxury of being able to carry TEMPO fuel for Singapore, so that's what we did. If we open up the possibility of using close-in alternates as SOP, that scenario would become much more the norm than the current system. I prefer the current system.
Somebody during the discussion has already mentioned risk mitigation. 99.9% of the time, the current fuel policy works.
Last edited by Shark Patrol; 30th May 2013 at 02:24.