FlyBTV
Posts: 73
Joined: Thu Jul 19, 2012 3:01 am

Transpacific 777F Flights - Fuel Burn Question

Wed May 08, 2013 6:31 pm

Quick question for those who are knowledgeable in this area: I've noticed that 777F operators such as FX or 9S occasionally fly direct HKG-MEM or HKG-CVG, for example. Other 777F flights on these routes include a stop in ANC. Obviously there are a number of reasons for the stop - crew change considerations, payload/range and the like.

My question is this: Assuming that the payload was such that an HKG-MEM (or similar) leg was feasible, is there a fuel burn advantage to flying direct? Obviously there is a savings from eliminating a second takeoff and climb from ANC, but is the additional fuel carried from HKG so significant that the added fuel weight negates any savings from the elimination of the stop?

Asked another way: Do these carriers eliminate the stop to save fuel, or are they actually flying direct to offer a more competitive schedule, time-wise?

As someone who regularly receives overseas shipments, I've always been curious. Thanks in advance!!
 
N809FR
Posts: 74
Joined: Sat Aug 21, 2010 6:10 am

RE: Transpacific 777F Flights - Fuel Burn Question

Wed May 08, 2013 8:51 pm

Now I have no personal knowledge of why they fly non-stop versus one-stop, however what I do know is that with FX the majority of their cargo carried is high volume, lower weight. Meaning essentially they may stuff the plane full and still be well under the weights requiring a stop. This is just my theory as to why they would fly non-stop.
 
roseflyer
Posts: 9606
Joined: Fri Feb 13, 2004 9:34 am

RE: Transpacific 777F Flights - Fuel Burn Question

Wed May 08, 2013 8:57 pm

I am guessing here, but if the cargo payload is low enough to go nonstop, they would prefer to go nonstop. If they have too much cargo, then they have to stop for fuel since they won't be able to fill up the tanks. Cargo operators always sacrifice fuel for payload since cargo doesn't mind a stop in ANC in the middle of the night.
If you have never designed an airplane part before, let the real designers do the work!
 
zanl188
Posts: 3447
Joined: Sat Oct 21, 2006 9:05 pm

RE: Transpacific 777F Flights - Fuel Burn Question

Wed May 08, 2013 9:55 pm

I understood this was one of the competitive advantages FedEx had with the 777 over UPS and the MD-11...

FedEx officials have called the 777 a game-changer because it will enable the company to offer later shipping cutoffs and other benefits.

http://www.commercialappeal.com/news...an/08/china-now-nonstop-for-fedex/
Legal considerations provided by: Dewey, Cheatum, and Howe
 
FlyBTV
Posts: 73
Joined: Thu Jul 19, 2012 3:01 am

RE: Transpacific 777F Flights - Fuel Burn Question

Thu May 09, 2013 1:57 am

Thanks for all the replies!

What piqued my interest in this was reading a discussion about ultra long haul flights and the concept of "burning fuel to carry fuel" which made very long flights economically challenging. Does a length such as MEM-HKG or MEM-SZX fall into the category where the length of the flight dictates a significantly higher fuel burn because of the additional fuel on board, versus a flight with a stop?

I'd imagine that there are additional expenses with the non-stop flight, such as the need for a relief crew on board (I'd imagine with a stop in ANC the flight should be able to be accomplished with a single crew, though I could be wrong). So I've been leaning towards the explanation that it's more of a competitive decision than an economic one.

I guess the ultimate question is this: what burns fuel more - flying a 777 HKG-ANC-MEM or HKG-MEM assuming an equal cargo payload and all other factors being equal?
 
User avatar
zeke
Posts: 9943
Joined: Thu Dec 14, 2006 1:42 pm

RE: Transpacific 777F Flights - Fuel Burn Question

Thu May 09, 2013 2:01 am

HKG to the west coast can have some nice tailwinds of over 300 kts at times, it can have dramatic reduction in trip times eastbound.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
User avatar
Starlionblue
Posts: 17119
Joined: Fri Feb 27, 2004 9:54 pm

RE: Transpacific 777F Flights - Fuel Burn Question

Thu May 09, 2013 2:13 am

Quoting flyBTV (Reply 4):
I'd imagine that there are additional expenses with the non-stop flight, such as the need for a relief crew on board (I'd imagine with a stop in ANC the flight should be able to be accomplished with a single crew, though I could be wrong).

You'd still need the extra crew members unless you had a long rest stop in ANC.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
rfields5421
Posts: 5651
Joined: Thu Jul 19, 2007 12:45 am

RE: Transpacific 777F Flights - Fuel Burn Question

Thu May 09, 2013 2:19 am

Quoting flyBTV (Thread starter):
Do these carriers eliminate the stop to save fuel, or are they actually flying direct to offer a more competitive schedule, time-wise?

FX is extremely cost conscious, but if there is enough money to be made by timely takeoffs and direct flights - they will do them if they have the right equipment available.

As zanl188 said - scheduling makes the 777F for FX an advantage option what the competition cannot compete with.
 
dfwramper
Posts: 29
Joined: Fri Nov 28, 2008 2:06 am

RE: Transpacific 777F Flights - Fuel Burn Question

Thu May 09, 2013 4:23 am

Quoting rfields5421 (Reply 7):
As zanl188 said - scheduling makes the 777F for FX an advantage option what the competition cannot compete with

I believe, but cannot locate a source right now, that FX was able to depart their aircraft 2-3 hours LATER than the competition and still offer an "overnight" service from Asia to the US. That's a pretty significant advantage in my opinion, particularly when the competition has to depart their flight at 5:00pm local. This means customers have to cut off shipping at 2:00pm or earlier just to get it to the airport, get it built up, and loaded on the aircraft. Those 2-3 additional hours with FX allow better utilization of the warehouse crew and better service (time in transit) to their customers -- a whole day earlier delivery in this case.
 
sunrisevalley
Posts: 5010
Joined: Tue Jul 06, 2004 3:26 am

RE: Transpacific 777F Flights - Fuel Burn Question

Thu May 09, 2013 11:33 am

Quoting flyBTV (Thread starter):
Assuming that the payload was such that an HKG-MEM (or similar) leg was feasible, is there a fuel burn advantage to flying direct?

Certainly if you are talking the same payload. HKG-ANC-MEM is ~16-hrs flying time; HKG-MEM is about 15hrs. From the load/range table for the 777F at a ZFW of 215t which is about 70t of payload , the one stop route requires a total fuel load of ~146t. The non-stop 133t. To give you some idea when a 77L burns ~7t/hr at cruise it needs 9.4t for a 36min takeoff and climb to initial cruise.

Who is online

Users browsing this forum: Bing [Bot], SoJo and 6 guests