Why would passengers on a diverted flight not be allowed into the terminal?

Question

I was recently on a flight to Washington DC, but due to adverse weather conditions at DCA we were redirected to Philadelphia to await suitable conditions to land in Washington. When we landed at PHL, we were told that we would have to remain on the plane because the airline didn't have client services at that airport. It's not one that they normally fly to.

After some time waiting on the plane, the flight crew announced that US Customs would allow us out onto the jetway so that we could at least stretch our legs and get some fresh air, but we were still not permitted to enter the terminal.

Why was the airline and/or US Customs and Border Protection not allowing us into the terminal? Does it have to do with the fact that the airline doesn't normally fly to that airport? Or maybe it was because PHL closes late at night? (We landed at 11:20PM EST and took off again at 2AM.)

Here are some details about the flight(s), if the specifics help. I'm interested in general regulations and policies that address situations like this, though.

http://flightaware.com/live/flight/SCX235/history/20160203/2340Z/KMSP/KPHL

http://flightaware.com/live/flight/SCX235/history/20160204/0615Z/KPHL/KDCA

Answer 1

I think the other answers do a very good job of explaining why you couldn't go into the terminal (the need to pay fees for use of the gate, use of personnel to board people afterwards, personnel to help disabled passengers, unaccompanied minors, etc). However, I'd like to clarify the customs part of the question:

Since you couldn't go into the terminal, the only other option was to let you "stretch your legs" on the tarmac. As I understand it, in international airports the tarmac area is a customs-controlled zone. The tarmac area of an airport is an area that has a lot of potential for abuse as far as customs/immigration is concerned, because there's a lot of mixing of people and goods of different status (e.g. you have airport employees, domestic passengers, arriving international passengers yet to pass through immigration, departing international passengers, and all these groups of people can have goods with them). You can see how if it wasn't controlled, it would be easy to e.g. sneak something or someone into the country. So, procedures exist to minimize and control this mixing in a customs-controlled area. So, likely one of the procedures is that the airline can't just decide to let people out of the plane without checking first. Also, it's a potential security risk, I wouldn't be surprised if airport security / TSA was probably involved in the decision as well. By the way, as I understand it, even if the airport only accepts cargo flights from international destinations, the tarmac area may still be a special customs zone.

Answer 2

If the airline isn't operating in this airport, then it means that they aren't paying any fee for using the airport services. Airport services aren't really pay as you use them. So a flight can't come and leave passengers like this...

Then it is also a matter of responsibility. What if the passengers start looking around and don't come back for the flight. The flight could be delayed even more and this woulf cost a fortune to the airline without elaborating on the schedule problems it could cause to the airport and others airlines.

Then for the customs, even if this is an internal flight, I guess they could do some random checks on the passenger list so if an unexpected flight comes, it could cause trouble to their organization even if I agree that it would be less of a problem than for an international flight.

Answer 3

My first official answer, so bear with me.

There are several reasons for this. There is a document created by the US DOT (here and more thorough one here) that pretty much covers all the reasons. It seems, primarily for the safety of the passengers (Enhancing Airline Passenger Protections). These are Tarmac Delay Contingencies.

Brief summary to answer questions:

• Since the airline had no presence at that airport, as other answers have pointed out, they have no means of providing any services for disembarkation/re-embarkation. I have personally experienced a rare case where another airline's operators helped with this and allowed passenger disembarkation. But, it's rare.
• Customs and Border Protection was involved per DOT policy. In the linked document, Customs and Border Protection is one of the agencies that should be coordinated with. The other being TSA. It depends on which one is appropriate. In the case of an airport that services international flights, Customs would probably be the appropriate one.

Hope this answers your question.

Answer 4

I'm sure there are various potential answers but here's a couple:

1. Some airports are "closed" with the exception of international flights. Depending on the origin country, some late arrivals are just necessary. So Customs might have had a say at that hour because it's just who was available.
2. The make-up of the passenger manifesto could play a role. For example, if you had people on your flight that required wheelchairs and those services were not available then it wouldn't be fair to them to release the passengers and have them unable to go anywhere. Same could be said for minors on-board. Much easier to keep everyone on the plane.