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I used go to St. Martin a decade or so ago. Hung on the fence line at Maho Beach and watched the take offs & landings overhead. It was always a landing on 10 with the approach over the beach and a takeoff on 10 with a sharp right turn after lift off towards the open sea to avoid flying over the mountains at the near end of 10. Seeing Air France A340’s and KLM DC-10’s wing tips swing almost over the fence line as they did their turn to line up on 10 for takeoff was great then. For those not having been to St. Martin, it’s weird not to seeing a dedicated taxi way along side the runway side, but instead feel your plane come to a stop on the runway, turn 180, taxi a 1/4 of the length of runway distance then make an abrupt 90 degree turn onto a short taxi way leading to the terminal pad & gates.Now as I watch “Live from SxM” on YouTube I see not only the usual landing & take offs, but periodically see airliners doing the reverse (taxi onto the runway do an abrupt left turn, taxi 10 to its end, do a 180 rotation there and takeoff using 28) [the Air France A330 was believable as they were doing a nonstop to Paris]. At the same time this was happening an Air Canada 737 was stopped, holding on the jogged taxiway to 10, (with two Twin Otters also holding behind) finally the 737 went to the end of 10, did a left 180 turn and then did what looked like a takeoff using 10. It then looked like they were aborting the take off as they got closer and closer to far end of 10 and the roadway & fencing without doing any upwards rotation). They finally did come to a stop, did a 180 rotation and then their takeoff towards us using 28. I also saw other A330’s hold 90 degrees to runway before be allowed onto runway to use it as a taxi way to 10, do a rotation for takeoff using 10. I know this sounds like wind reversal has come into effect, but both light planes(up to twin Otters & GulfStreams)and other 737’s & A320’s United, Spirit, American, Jet Blue were still continuing to use 10 to do all flying in & out both before and after this event. Weather was clear ,sunny, 82 degrees.In short, why would some aircraft reverse takeoff direction and others not? It has never happened to me on a 737,757, or DC-9 flight. Does aircraft takeoff weight mitigate the take off direction, no matter which way the prevailing direction of the wind is? When I see this at LAX, if their E or W winds change direction everybody changes landings and takeoff directions.
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I haven’t been there in a long while so I’m not entirely sure…but there is terrain at the end of 10. Even though everyone flys the same planes sometimes we pay for different data and then will do different things.
In STT we take off downwind to avoid the small hill east of the airport. It’s supremely embarrassing to sit there burning fuel trying to get under rwy takeoff weight (worse downwind) and waiting for the tailwind to be just barely within limits while everyone else blasts off to the east over said small hill.
I could also see after some of the deaths at SXM airlines saying “if you have the performance numbers and arrival flow allows take off over the beach so you don’t blow anyone away”
All the performance numbers interact and change. So possibly a 5-10kt tailwind is less limiting taking off over an open beach than a 5-10kt headwind pointed at a mountain.
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I don’t have a specific answer but an anecdote that might help explain things. Last year the Nasa Super Guppy visited Nasa Ames at Moffett Field. The weather/winds were switched from the “normal” with planes taking off to the South and landing from the North. A friend and I went out for the Guppy landing. Since ALL of the aircraft were coming in from the North we headed to the North end of the field. Guess what? The Guppy landed from the South 🙂 In a few hours it was the ONLY plane that landed from the South.
I assume that all planes/airlines may have slightly different parameters. So yes most all planes should land/take off in the same direction but there are no guarantees. At SFO when the weather gets “iffy” it gets quite interesting with different airplanes/airlines taking different runways due to their procedures. Some planes takeoff and some wait for either a change in the winds or a different runway.
Ken
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Hard to say without more information. Couple things I can think of:
- Wind shift.
- Everyone else was ok with a tailwind takeoff, but AC needed more runway due to being heavier for a longer flight.
- Different op spec limits on tailwinds or reduced-thrust takeoffs
- Chime from the cabin, low-speed RTO, figure out cabin issue, winds calm, let’s take off the other way.
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I’ve seen that that a couple of times, last one was a TSC A310. Asked around and the answer I got most often was aircraft weight and engine out performance departing over the mountains.
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Thanks a lot ‘Stevej’. My thoughts were similar. As the loaded Air France A330 (to Paris) went directly to 28 runway from the gate could be expected, as gives it a low gradual climb out it. However, the Air Canada 737 was weird. No doubt a planned non stop flight to Toronto it would have been heavy with fuel and passengers so would’ve wanted a smooth gradual climb out to minimums. A late V2 at SxM on 10 makes for a perilous climb out while turning seaward to avoid the mountain at the foot of 10. Their action of a high speed taxi to the end of 10 then a reversal taxi back to use 10 again (might’ve been embarrassing to them). Or maybe what I did see was an aborted take off on 10 that made the crew ask for 28 usage to get smooth climb out rather than redo another 10 takeoff. 10-28 will have to be remade someday; maybe 12-30 with extensions having a unobstructed, higher beach elevation for approaches/departures at both ends with overrun extensions. So I say, visit SxM soon to see the close up landings and take offs before their gone.
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