QF 108 ex JFK-LAX 20/12/12

[Peter H.]

Am I stupid or just can't understand. My son is due back on QF #108 today Sat in Syd . In LA was handed a letter (for insurance purposes) saying due strong head winds forecast will be flying via Brisbane arriving Syd approx 2hr10 late

Check of Syd Airport arrivals both United 747 flights -who would encounter same conditions- are due in 1hr late and 41min late. How can they do same flights and not have to divert. Brisbane stop is for refuel only-no disembarking allowed so a nice sit of 1hr20 for what?

I cannot understand. Several years ago I flew QF to LA and overflew airport and landed Las Vegas to refuel so we could land in LAX which we overflew. Explain that one if any experts out there

[Sarah C]

Well it didn't stop in Brisbane, it went to Nadi but is arriving about 3 hours late. The technical wizards on this forum will give you a better answer but clearly looking at the weather, they planned for a delay due to the weather. The other airlines might have flown a different route - at least they told you in advance. It is the same problem QF faces with Dallas on a regular basis - the weather changes so much, they make plans to divert that don't evenutate or they have to divert (and it wasn't planned).

[Peter H.]

Thanks Sarah but if you go to Brisbane airport arrivals it has landed there

How can anyone work anything out with Qantas

[Mick F]

Settle down mate, it's hardly Qantas' fault that it's a bit windy.

There are many different variables as to why they had to refuel and others didn't. Maybe they have different engines, that burn more. Maybe they were heavier out of LAX and therefore weren't able to climb as high for a while. That'd make quite a difference (higher fuel burn). There are many different variables. When you're talking 4 jet engines on a large aircraft, over 13hrs of flying, it does not take much to put your fuel burn out by a couple of tons.

Your question about overflying LAX and going to Las Vegas. Perhaps LAX had developed a weather problem on the way which required more fuel to be in the tanks than what was required to fly to Las Vegas. Eg. it might have only been another 40mins to Vegas and no holding required, but LAX might have required say 1hrs holding fuel plus diversion fuel.

Mick

[Nigel C]

Maybe they have different engines, that burn more.

United uses P&W engines, Qantas have RR and GE on the B747's. I've no idea on the burn rates.

[Todd Hendry]

Peter,

Firstly I apologise for the delay of your sons arrival.

But by now I'm assuming he is home and safe.

To try to answer your question I have to guess a few things. So my answer will technically be a hypothetical one.

Ok. Here goes......

The QF flight was full of Pax and or cargo which would increase the fuel burn by about 400kgs of fuel per 1000kgs of extra weight carried compared to a lighter 744.

Domestic sectors between BNE, SYD, MEL, PER are all basically all slot times with minimal change allowed to the time. So if the QF108 was ready to go 1 hour before its slot time it can't.

Also the Pacific is flown using UPR's which is user preferred routes. Can't see a lot of difference in the flight plans happening but the united routes may have been better.

And to answer your LAX , LAS question,

The weather in LAX must have changed along route after the flight had departed and required extra fuel which was not carried. On reality it would not have probably been needed but was legally required.

These rules have been formulated over many years and have been designed to increase safety.

I'd rather be late than run out of options.

Any more questions let me know.

Todd.

[Max C]

http://flightaware.com/live/flight/V...740Z/KLAX/YBBN

http://flightaware.com/live/flight/V...100Z/NFFN/YSSY

[KVS Availability Tool 7.1.2/Diamond - Amadeus Operational Info: QF 108/20 Dec 2012]

Planned Flight Info
Segment Departure Arrival Duration
------- --------- --------- --------
JFK-LAX 18:30/Thu 21:30/Thu 06:00
LAX-NAN 23:40/Thu 09:10/Sat 12:30
NAN-SYD 10:00/Sat 12:35/Sat 04:35


Location Time Operational Event
-------- ----- ---------------------------
JFK 18:45 ESTIMATED TIME OF DEPARTURE
JFK 19:12 LEFT THE GATE
JFK 19:42 TOOK OFF
LAX 22:00 ESTIMATED TIME OF ARRIVAL
LAX 21:53 AIRCRAFT LANDED
LAX 22:12 ARRIVED
LAX 23:40 ESTIMATED TIME OF DEPARTURE
LAX 00:34 LEFT THE GATE
LAX 00:51 TOOK OFF
NAN 09:10 ESTIMATED TIME OF ARRIVAL
NAN 09:11 AIRCRAFT LANDED
NAN 09:15 ARRIVED


From all that it looks like BNE was Plan A, however it ended up being NAN.

3 hr delay is better than leaving people behind.

[Sarah C]

Could the aircraft operating not be an 747ER? (ie was it OEB?) That might explain it.

[David Ramsay]

QF8 (OEJ) was at NZAA this afternoon (24/12). I'm guessing the strong headwinds are still around.

[Brad Myer]

Not a big deal really...

I've seen UA divert many times while all the QF flights continued as normal.

As for the Vegas diversion... Most likely caused by long ATC hold times in LAX, more fuel probably required before re joining the approach line up.

Hope this helps