flyBTV From United States of America, joined Jul 2012, 23 posts, RR: 0 Posted (11 months 1 week 5 days 16 hours ago) and read 3139 times:
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 From United States of America, joined Aug 2010, 181 posts, RR: 2
Reply 1, posted (11 months 1 week 5 days 14 hours ago) and read 3085 times:
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 From United States of America, joined Feb 2004, 9375 posts, RR: 52
Reply 2, posted (11 months 1 week 5 days 13 hours ago) and read 3079 times:
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!
flyBTV From United States of America, joined Jul 2012, 23 posts, RR: 0
Reply 4, posted (11 months 1 week 5 days 8 hours ago) and read 2940 times:
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?
Starlionblue From Greenland, joined Feb 2004, 16908 posts, RR: 67
Reply 6, posted (11 months 1 week 5 days 8 hours ago) and read 2928 times:
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."
DFWRamper From United States of America, joined Nov 2008, 56 posts, RR: 0
Reply 8, posted (11 months 1 week 5 days 6 hours ago) and read 2871 times:
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 From Canada, joined Jul 2004, 4603 posts, RR: 5
Reply 9, posted (11 months 1 week 4 days 23 hours ago) and read 2776 times:
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.