Trains can't leave before their departure time right?

[Devil's Advocate]

I think some of the suspicion about weather delays comes from the vagueness of the explanation (front line staff tend to be rather terse) and that citing weather avoids compensation. With improved airline apps and flight tracking sites passengers can see more of the big picture than we could in the past but I can understand why someone who suffered an extended delay under clear skies might think they were being played. I personally stay away from airports in the Northeast and Great Lakes regions over the winter holiday period and I avoid problem airlines like Spirit and Allegiant since they seem the most inclined to shirk responsibility for delays.

 

[west point]

What seems to happen both thanksgiving and Christmas/ new Years that one or more airports get socked in. then airplanes do not arrive to make their next turn and beat goes on.

 

[Asher]

As Istone 19 pointed out. "One more thing - wind is weather. So if a flight departs on-time but arrives late due to enroute winds, at least my airline would say the reason is weather (it might be ATC but weather and ATC reasons both went into the same higher level delay reason"

On a flight to Guaymas Mexico last week, the trip down from Lancaster Ca. Was 4 1/2 hours total time. The trip back was over 7 hrs. And the reason head wind. At the bottom left of the first photo you can see ground speed 65.6 kts ground speed and over on the bottom right is the head wind with a arrow at 57 kts.

The second graph from Calexico to Lancaster shows altitude and ground speed all over the place for half the leg, getting better later. No clouds, rain, good visibility. Just Wind, had it on the tail going, got there early. Fought it coming back, sloow trip.

 

[lstone19]

One additional thing about enroute winds: there is both seasonal and daily variation. We had a good handle on seasonal variation (winds are normally out of the west with stronger winds in winter) and divided the year into five seasons to account for the seasonal variation. Domestically, we had lots of schedule latitude. Internationally, due to how most airports outside the U.S. manage slots, we were usually tied to a fixed arrival and departure time for the entire Summer or Winter industry season so could only vary times on the U.S. ends. (the industry seasons are Summer from the last Sunday in March to the last Saturday in October with the rest being Winter - those dates correspond to when Europe goes to and from DST).

But while we knew what the seasonal variation would be, daily variation dwarfs it. If the history and wind model said a market should expect a 30 knot headwind in summer and a 50 knot head wind in winter, a given day in summer might see anything from a slight tail wind to 100 knot head wind. On a six hour flight, that 100 knot wind, 70 knots over plan, is going to add an hour to the flight (but daily variation that extreme was pretty infrequent).

There was one international market where the seasonal variation was so extreme (about 100 knots) that we did monthly block times for it. Lots of manual work on my part as much of the automation we used to support making our forecasts did not go that level. The westbound longest block time in winter was about 25% longer than the shortest time in summer. And even then, in April when the wind really started dying, it would not be unusual to have no westbound on-time arrivals for the month by today (April 9) and yet I could state with reasonable confidence that we'd get to 50% by the end of the month as once that wind change kicked in, we'd start arriving early.

 

[jis]

On a nonstop from Mumbai to Newark, there have been times when we arrived 75 minutes early and then had to sit in the plane waiting for the CBP facility to open at 5am or some such! It was on a relatively low wind February day AFAIR.

 

[PVD]

Or the arrive early and no gate is available, or arrive very early on a red eye and no ground crew to serve as marshals or move the jetway.....

 

[west point]

Los Angeles to New Zeeland and Australia have very different arrivals due to winds. It can be so bad in winter that even the longest range aircraft have to fuel stop going west. These winds really make computing the equal time point difficult. ( ( also know as the incorrect term point of no return ) Crossing the equator is also a cause of wind directions changes Once arrived LAX 2-1/2 hours early. We did leave early as all passengers were on board.

 

[lstone19]

On a nonstop from Mumbai to Newark, there have been times when we arrived 75 minutes early and then had to sit in the plane waiting for the CBP facility to open at 5am or some such! It was on a relatively low wind February day AFAIR.

That sort of stuff happened a lot at my carrier. Sometimes it was because the flight crew, not understanding CBP hours, sped up thinking they'd get to bed earlier than planned only to sit until scheduled arrival before the door could open.

We had one flight that became a big problem because it was sandwiched by a departure curfew at the origin (had to depart no later than time) and CBP hours at the destination (had to arrive no earlier than). We tried to tell the departure station not to push it early and the flight crews to slow down but they don't always listen.

When circumstances permit, when the flight plan time comes in low, you have to deliberately take a departure delay so you don't arrive too early. We had one market where the destination arrival slot was 0610, you weren't permitted to land until 0601, and planned taxi-in time was six minutes (so scheduled landing time would be 0604). We were trying to hit a three minute window from 14 hours away. I did an analysis showing that we should expect to take a "destination curfew" departure delay more than 50% of the time which did not please upper management who thought on-time departures were all that mattered.

And then there's London-Heathrow where the slot people want you to comply with your slots, the curfew people don't want you landing before 0600, yet for historical reasons, there are pre-0600 arrival slots. Managing a flight with an 0555 scheduled arrival and also keeping the curfew people happy was lots of fun.

 

[west point]

Istone: Larry you and I have had a lot of experience with these problems. You are right about CBP being a pain. Arrived MIA as passenger one time just before thanksgiving with a fairly bad injured flight engineer. CBP did allow him off after about 15-30 minutes by EMTs Because of backup and late arrivals of other AC ahead passengers had to wait 2 - 1/2 hours to even get off aircraft. What really torqued me off was other flight crew allowed off without any FAs in case of emergency. Wrote letters but was politely told to drop it or else.