Why would a commercial airplane leave earlier than scheduled?

Factual Questions
21

There are an unlimited number of reasons a plane would depart early. Just from a logistics POV anything that would delay any plane down the road would justify it. Crews about to run out of duty time that can’t be replaced. The connection of jump-seat crew to another plane at the next destination. maintenance issues (parts on-board to connect another plane). Presidential visits that shut down an airport. Weather.

Monetary issues such as high density cargo (dollar density). Low density passengers ($20 super saver passenger versus high dollar space-available business passenger at next stop).

22

I couldn’t tell you why the OP’s flight left early, however, one common misunderstanding that I have come across countless times is this (at least for my airline, and I assume all others): There is a posted departure time- This is the time you see printed on your ticket, posted on the connection boards, and at the gate screens overhead. For the airline, “departure” means the the time at which the boarding door is closed and the parking brake is released. This is recorded automatically through electronic means.

Typically, the airline will cut off boarding at some pre-determined amount of time PRIOR to the “departure time”, so that the final passenger and bag counts can be delivered to the pilots for weight and balance reasons, and that any discrepancies can be addressed and corrected so the aircraft door can closed on time. For my airline, most flights cut off boarding 10 minutes prior to departure. So, if your ticket says 2:30, and you arrive at the gate at 2:25, there’s a good chance you’ll see your plane pushing back already.

For compensation issues and determining whether the airline is obligated to compensate an inconvenienced passenger in any way, and the extent of compensation due, please download and read your airline’s “Contract of carriage.” Keep a copy saved on your phone if you have one capable of doing so. Usually found on the airline’s website, the contract of carriage defines the rights and obligations between parties of the contract. (which is you, and the airline) I don’t know of any carriers that will buy a hotel room for a weather-related delay. Delays or cancellations due to other reasons may be due compensation. Know what’s in your contract of carriage! =)

23

That’s not always true. I once had a connection in San Francisco for plane to Sydney, and just made it running across the terminal. Of course, my luggage caught the next plane, 24 hours later, but that was not a big problem for me or for the airline.

I’m not aware of any airports in the U.S. where there are transit lounges. Passengers connecting in the U.S. from one international flight to another must go through immigration and customs, and must be either eligible for a visa waiver or must have an appropriate tourist or business visa. That means that, if they have a long time between planes, once they’ve gone through immigration and customs, they can leave the airport and see the local sights if they wish.

24

Whoah. Apparently that’s another reaction to 9/11, I’ve come to discover when attempting to contradict you. Apparently these days you do have to clear immigration and customs at the first port of entry. That sucks.

25

The rule is that passengers may not separate themselves from their luggage. Airlines are allowed to, either deliberately or accidentally. In this case the airline did it.

26

Not much to add here conceptually. Here’s a few arcane details & insight into the thinking …

My company’s policy is to normally stop boarding about 7 minutes prior to published departure time. If you’re not past the boarding pass scanner & terminal-to-jetway door by then, you’re not getting on. Getting everybody seated, bags stowed, bins closed, seatbelts checked, PAs made, and gate-checked strollers & wheelchairs stowed below decks takes that last 7 minutes. Then we push back as soon as we can, typically on-time +/- 1 minute.

The computers are tracking all the passengers. Once the gate agent gets notice that all expected passengers are on board, they *will *close the boarding door even earlier. Like up to 15 minutes prior to departure. Which leads to us actually pushing back about 8 early.

So if you are running to try to make an earlier flight than your reservation says, you may well be left behind. Conversely, if you’re running to make the flight in your reservation, we know that too and will normally wait at least a couple minutes for one person or several minutes for several people. The agent knows who is running from which gates and when their previous flights arrived. So they know about when to expect the runners to get to our gate. I don’t know the specific decision logic they (or the big computer in the sky) use, but waiting a 3-5 minutes for runners is common.

And that’s the story for a normal run-of-the-mill departure. Then come the special cases.

Our real goal is to *arrive *on time or early, not necessarily *depart *on time. DOT on-time statistics are based on arrival time. If we’re heading into a hub or an international gateway, folks depend on us arriving on time to make their connections. So the company plans, and we execute, to make that goal.

The published flight schedule starts with an expected taxi-out time based on the specific airport & time of day & planned congestion. Same for taxi-in. The scheduled time from takeoff to landing is based on the cruise speed of the planned aircraft type, the statistically typical route, the statistically typical winds for that time of year, and a factor for expected airborne congestion. Then some padding is added to cover for the daily “stuff happens”. The published arrival and departure times you see are built from that total duration.

If weather, airport or ATC issues, unusual winds, or a change in aircraft type mean that today’s flight will run longer than scheduled, we try to solve that. The best (read “cheapest”) way to do that is to depart early. Which we will do up to 15 minutes, but not at the cost of deliberately leaving people behind. If that’s not enough or we can’t leave early and still accomodate everybody, then we leave as soon as we and we can fly up to ~10% faster. At enough marginal extra cost to guarantee this flight was unprofitable.

Finally, occasionally we get into the “here comes a big storm; we either leave 30 minutes early or 3 hours late.” Or the equivalent situation is expected at the destination at our arrival time. That’s pretty darn rare though. Rare as in I do that once every 2 or 3 years of full-time flying. But if we are in that scenario, then we’ll leave early with as much load as has shown up. Sucks to be you if you get there after we’re gone.
A helpful tip: If you check in online & get your boarding pass before you leave for the airport, we *know *to expect you. If you plan to check in when you get to the airport, we *don’t know *to expect you until then. So if you’re delayed in traffic, you may get left behind, whereas if you already had a boarding pass we might not have left early or might even have waited a few minutes.

27

They did get him to his destination, if late. I don’t believe airlines in the US are very obligated to you in weather-related situations these days. He was also flying on frequent flier miles, but from a credit card, not from being at a premium level.
I think he also would have been just as happy to turn around, but couldn’t because his luggage was sent on.

28

It didn’t used to be this way. When I was in college, 40 years ago, we missed a connecting flight to Corpus Christi in Houston, and we got a hotel room and a voucher for a real (non-airport) dinner.
My daughter was stuck in the Heathrow disaster just before Christmas and she was eventually compensated, if not helped, by BA. However the EU came down hard on them, and without this it is not clear she would have been. EU rules are different from our rules in any case.