Yes, always.
You do not need a passport to fly from London to Newcastle-upon-Tyne, as both locations are in the UK, however it is always best to take your passport with you just in case.
No you need a passport.
It is regarded as an internal flight, but you should bring a passport with you any time you are flying.
Although both Greece and UK are in the European Union you still have to show an up to date passport in and out of both countries.
Yes, you need a passport to fly internationally.
Yes, you need a passport to fly internationally.
Yes, you need a passport to fly out of Tijuana.
Probably. You do not need a pasport but you do need photographic identity. Check with the airline.
Yes, babies need a passport to fly internationally.
No, you shoudn't because it is part of the United Kingdom.
Yes - and it has been the case for a long time. However, you do not need a visa and it is extremely unlikely you will get your passport stamped
Yes. You need a passport to fly anywhere.