It is regarded as an internal flight, but you should bring a passport with you any time you are flying.
You will need one, and maybe even more documentation, such as a visa, depending on where you are coming from in the world.
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.
Yes, always.
No you need a passport.
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.
Probably. You do not need a pasport but you do need photographic identity. Check with the airline.
Yes. You need a passport to fly anywhere.
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 require a passport to fly to London Ontario from England. Similarly if you fly to London England from Manchester via Hong Kong you will need a passport +++ Not sure why you'd fly from Manchester to London all of 200 miles away, via Hong Kong! No, you don't need a passport to travel within the UK, BUT the airports demand ID for security, and your passport is usually the most reliable.
Yes you need a valid passport to fly from Glasgow to Spain.
Yes, you need a passport.