Set up your Apple ID with the security questions. You should only have to do this one time. Once that is set up, you should be able to install apps from that point forward. If it times out on the first one, just finish setting up the security, get that done. Then go back to installing the app.
Is it the Delta app that is asking for the security questions? Can you set up the Delta account on your computer first? Then try to install it on the phone? Would that get around the timing out issue?
I was on the phone for 3 hours yesterday with Apple. Apple has my case at the developers stage. Looks like it's a problem with my Apple ID. When I go to a laptop, only 1 security shows up, when I go from i5s, it wants to create 3 questions, then times out
Sent from my iPhone
OK - I hope Apple can get it resolved for you!