I told him I thought that was strange.

That's pretty ominous and obviously suggests some sort of hijacking plan.

His excuse is weak, he just wants to learn how to do it... That's pretty ominous and obviously suggests some sort of hijacking plan.

Although I did create problems for myself, I had no other choice.

It would have triggered an immediate attempt to gather every piece of information we could about the plan, the targets.

I would have immediately sounded the alarm.