AA55 low fuel stop at goose bay AFB
 

well we had a little but somewhat inconvenient adventure yesterday. was on the AA055 MAN-ORD and at the checkin staff were handing out letters advising that due to "strong winds" we would be making a stop in Newfoundland, Canada.

this we duly did, and after about 40 minutes on the ground we were on our way again to chicago, with the whole trip having taken about 10.5 hours.

we then had to wait 75 minutes in the immigration line as well, but that's another story.

the staff at AA didn't seem to think this was out of the ordinary, but then they do only operate a B757 on that route. I would say seats were about 85% full. Is that normally a good reason for such an epic diversion ? Would a 767 also not have enough fuel to make the trip? Or are they overloading us weight wise ?

Headwinds can be more than a breeze. Check our this recent thread:
http://www.pprune.org/passengers-slf...don-track.html

This is all about the effect of headwinds on the speed of the a/c. Just the same when you are in a car on the motorway, except that the headwind might be 100mph or (as I understand it) even more. That means more drive needed by the engines to fight it and that takes fuel. Somewhere around the world, this is an everyday occurrence.

I have no idea why your flight would have done its on-route diversion, but a look at a Jetstream map is always interesting.

Here's one

B757 v B767
 

Both would be flying under ETOPS, but the 767 could have, potentially, approx 19T more fuel available (dependent upon certification and varient R/MTOW).
I could imagine that this would be sufficient to operate MAN-ORD direct.

Tightslot is correct, tech/fuel stops are more hassle.

Very strong headwinds across Atlanic last few days, i did AA63 CDG-MIA on Friday, flying time just short of 11 hours, much longer than usual made connection to next flight very tight but just made it!

Legal reserves for Commercial flights are substantial and maybe due to some weather routing and headwinds they were getting close.

Proceeding on legal reserves when you have an alternate is a No No.

A certain African airline was banned from heathrow (an thence EU airspace) after landing on vapours and not declaring an emergency.

i've seen just now on flightaware they stopped in there again on 28th feb (monday). i just think they should seriously consider flying some bigger metal on this route to avoid these stops.

I flew Denver to Heathrow on a BA B777 on the morning of the 25th February. The moving map on the inflight tv (dunno how accurate that is) was showing a tailwind of 179 mph at one point. It was quite bumpy and the cabin crew had to strap in for a while until the driver eased it a bit further north of track and into a more sedate 85 mph tailwind. A lot of severe weather over the Eastern US at that time.

Flight time was reduced from a normal 9 hours to 8 hours! I imagine that flying westwards would have been very slow progress.

DUB to MCO
 

I was on EI121 (A330) DUB to MCO on 22 Feb and the Captain announced headwinds circa 90kts. The flight took 27 mins more than scheduled.
On checking I see the return flight to DUB knocked 33 mins off its scheduled time.

Deep down in the southern hemisphere, the Perth-Johannesburg leg gets some really strong winds. My fastest time going east was 8 h 15 mins, and going westwards, times can be well over 11 hours. Not too many refuelling stopsin between, unless you deviate rather far north to Mauritius.

That's a different matter. The aircraft in question is nowhere near the limit of its endurance, and there is further contingency fuel taken where there is no possibility of a fuel stop (although presumably Durban westbound offers an opportunity).

In contrast 757 operations across the Atlantic, especially to somewhere as far west as Chicago, is knowingly pushing things to advertise nonstops in winter, but can be done because they do have all sorts of options along the way, and the stop, as here, may well be anticipated.

Correct me, somebody, but are the major US carriers worse at scheduling such maximum endurance flights for smaller types than others ? There are so many accounts of transatlantic 757s (a US carrier speciality in this market) needing fuel stops westbound in winter, and exactly the same with A320s and 737NGs making full US transcontinental flights and having to fuel stop at Las Vegas or somewhere, in comparable conditions - neither of these missions being what the aircraft in question were designed/optimised for.

TS

Actually the answer is quite straightforward; it is to assign an aircraft type to the flight which has adequate endurance to handle likely weather conditions. Needing to do a fuel stop on Transatlantics has only come back in any way in the last few years as 757s have come onto these flights at the edge of their range. Before that, when 767-200s and A310s were the smallest types on such services such stops had been unknown for years.

It's not that 757s had not done Transatlantics previously, they have done charters from Europe to Florida and the Caribbean for many years, but these have always been broken down into two medium haul sectors, say London to Gander and Gander to Montego Bay.

US carriers don't care about onward connections from westbound Transatlantic flights, because they have the belief that rebooking can always be sorted out on arrival at the hub, onto their next "frequent" flight to any of their destinations. Regular travellers who have experienced this situation, however, know differently !

It may be presumptuous to say the aircraft don't have the range. Full fuel isn't automatically carried on a long journey. Extra fuel tankered for a trip is expensive, and gets needlessly burned. Typically 4% of the fuel tankered gets burned, just to carry that extra weight, though this can be substantially more, depending on just how heavy the aircraft is.

Winds aloft can be strong. I had 200 knot winds recently over the Pacific. North Atlantic winds are not usually that strong, but going westbound certainly slows a flight. For flights that are conducted under re-release rules, the key issue is the amount of reserve fuel necessary for a long Class II navigation segment (the oceanic part). On a re-release flight, the total fuel reserves are reduced, provided that by a certain point on the trip, the company is contacted for an update and recalculation of the flight performance data. If the crew and company jointly determine that adequate fuel remains to make the remainder of the journey, then the flight continues.

If, however, a determination is made that fuel burn is too high, a diversion will be necessary. Evidently this flight diverted for fuel.

It's important to note that the flight wont' be operated at any time unless enough fuel reserves exist to be safe, but the re-release function on certain flights is there to allow a flight with reduced fuel for efficiency. Clearly a stop isn't efficient, but where field conditions are different than forecast and other events may conspire to increase fuel burn, a stop may be necessary.

In my opinion, it very much depends on the inconvenience it causes.

On business, if I book a non stop flight, then I expect it to go non stop and I plan around that, accepting that one may encounter delays occasionally.

If I missed an onward connection due to a non stop flight becoming a stopping flight, then I would become at least irritated.

One of the reasons I like to use British Airways for long haul is that the company does have a fleet of aircraft that are fit for purpose, all year round.

No. But the CAA could require that if you can't achieve the schedule more than, say, 98% of the time without being forced ino a stop, then you should advertise such a possibility in your schedules. That's some 7 times a year. From what I hear several of the 757 routes are stopping much more than that.

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I'm really, really not spoiling for a disagreement on this one WHBM

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Indeed not TS - its just since US carriers started drafting 757s onto Transatlantic routes there has been a great expansion in unscheduled and disruptive fuel stops by these aircraft on the extremes of their range, previously unknown. It doesn't do the business any credit.