Or fuel in the tank.

And it’s probably being blocked in by other planes. Those desert boneyards don’t park planes with random access in mind.

Looks like they leave fuel in the tank if it’s for short term storage, but they drain various fluids if it’s longer term storage. Probably depends on the circumstances.

Precisely—and this circumstance is retirement with no prospect of a quick sale.

At a guess, they’ll probably have limited parts value, only that which would be valuable to operators of 747 freighters. Mainly the engines, if they’re in good nick.

As a random fun fact planes don't have keys.

Do they have some other authentication mechanism instead?

The authentication method is knowing how to fly said plane and getting in said plane in the first place.

The planes that are relatively accessible aren't flightworthy without effort, and the planes that are flightworthy require violating federal law (in the US) to access them.

>and the planes that are flightworthy require violating federal law (in the US) to access them.

That doesn't really answer the question though. Breaking into a house also violates laws, yet it happens all the time. If you've made it onto an airport tarmac, can you just steal a plane?

It's logistically very difficult. Getting fuel into it usually takes a special truck, so you'd need access to that (when a plane is parked overnight it would have a little bit of fuel in it, but not enough to get very far after taking off). Even getting into the plane is difficult - you'd need a stair truck, and somebody to move the stairs out of the way when you're in. If it's parked somewhere where you can't just taxi out, you need somebody in a tug to do a pushback.

So assuming you're that far in, and you know how to start it up, you don't have a flight plan logged, so the tower isn't going to give you clearance to take off. If you take off without permission, they're going to call the air force, so you'd better be in a country that doesn't have a very big air force or a nearby base, and you probably want to choose somewhere where you can get into another country's airspace who isn't friendly with the country you stole the plane from...

it's easier than you might think. for example, on a 747 you don't need external stairs, since access is available via the nose wheel landing gear bay [0] according to a pilot.

0. https://aviation.stackexchange.com/questions/2605/can-large-...

It's happened before

https://en.wikipedia.org/wiki/2018_Horizon_Air_Q400_incident

https://www.cnn.com/2018/08/12/opinions/seattle-stolen-plane...

> most airlines do not lock airplanes because access can only be obtained by security vetted employees through jet bridges and coded door ramp access.

I don't think the law was a deterrent to 9/11 te'rists.

Airliners generally do not.

Some small ones do.