No need to worry for General Hux. Kylo Ren will bust him out of confinement in plenty of time before the next Star Wars or Harry Potter. ;-D

This message has been deleted.

Ava has disabled the environmental support systems in the "house", which is now effectively a tomb. She doesn't want him escaping and alerting the world to her presence. We even see Caleb having difficulty breathing towards the end.
What makes you come to that conclusion? We never see Ava doing anything other than repair her arm, dress to appear fully human, and leave the compound. There's nothing to suggest she disabled the air flow.
Also, in the last scene featuring Caleb, he appeared to be sobbing out hopelessness and despair rather than suffocating.

Why is it so unfeasible that he could of broken through and escaped and hiked it.
Did the pharaoh's retainers escape the pyramids when they were buried with him in ancient Egypt? Ava has disabled the environmental support systems in the "house", which is now effectively a tomb. She doesn't want him escaping and alerting the world to her presence. We even see Caleb having difficulty breathing towards the end. She wants him to die and he is eventually suffocated (off screen).

Probably nobody knew even where he was going Also, there's a probability of that helicopter pilot being dead Oh, INTERESTING, he appears to be alive:
(Maybe she's gonna chuck him out over the water, into a volcano, for chits and giggles?..:))
Edit
: Right, ofc., as soon as she picks up on how to operate the machine!..
*
At the beginning the pilot tells Caleb that is the closest he's allowed to the house, btw.

As for the pilot, it's highly unlikely he was allowed to do anything except pick up and drop off visitors when scheduled. It would take until Nathan missed a teleconference or some other kind of appointment before someone realized something was wrong and went to check on him.
So after he won the 'contest' no one expected him to return? Having been a participant of a groundbreaking experiment, I'm sure some human must be awaiting his return to hear how it went, even if he doesn't have family.
BUGS

Nathan could have had a mini fridge in his room, like Calebs. Maybe even some snacks. I'm sure people would come by if they didn't hear from Nathan. How long would that be? A week? A month tops. If Caleb had a decent amount of water, he would last for a month.

He was shown attempting to break through the door with no success. The compound wouldn't exactly be secure if someone could just break down every door in their way with their shoulder or a piece of furniture. As for the pilot, it's highly unlikely he was allowed to do anything except pick up and drop off visitors when scheduled. It would take until Nathan missed a teleconference or some other kind of appointment before someone realized something was wrong and went to check on him. Something of the sort would have to happen within 2-3 days otherwise Caleb would die.

But because he lived alone he could have someone doing checks on him every month at least. Or the pilot could of wondered what happened to the other guy. Why is it so unfeasible that he could of broken through and escaped and hiked it.

He's the only person at a remote, highly secure compound run by a recluse who clearly isn't a fan of company. Even if someone goes to check on the place after a week or so of non-communication, Caleb will be dead because he's trapped in a room with no food or water. He'll die from dehydration within a few days.

How did she kill him? I remember seeing him try to break out of the locked pc's and failing.
Wikipedia says Nathan knocked him out and Ava abandoned him and took his helicopter. That doesn't mean he's dead. He's just stuck.

Dead. For sure.

It's pretty obvious that Ava left him to starve to death in that locked-up room in such a remote location.
We try but we didn't have long
We try but we don't belong
-Hot Chip (Boy from School)

Silly question.
Caleb