Was the Battle of Britain the Royal Air Force's greatest moment since its formation 100 years ago?
Or was there another achievement that eclipsed it during an amazing, heroic century?
A new book, 'The Royal Air Force - The First One Hundred Years' is set for release later this year, chronicling the history of its magnificent men and women in their flying machines.
Forces Radio BFBS presenter Chris Sturgess asked much-respected aviation historian, broadcaster and pilot Paul Beaver, co-author of the new book, to list his top five greatest RAF moments...
"[Number five] is probably going to be the Berlin Airlift... along with our allies the Royal New Zealand Air Force, the Australians... the Canadians... the Americans."
"I think number four you're going to have to say that that is the concentrated ability of the Royal Air Force to take air power around the world in-between the wars.
"It's not necessarily a conflict but it's preventing conflict and I think that's equally as important as attacking people.
"Number three - and this will be very controversial - is the Battle of Britain. The reason that this is number three and not number one, is because it was quite a short campaign and it wasn't just the Royal Air Force."
"It was the whole nation. It was GPO [General Post Office] telephone engineers [who carried the sole responsibility for providing telecommunication services across the country until 1982] and girls in factories in Salisbury and Trowbridge making Spitfires.
"It was a whole raft of things, not just the Royal Air Force.
"Number two I think is the way in which the Royal Air Force operated in the Middle East in the post-Cold War period.
"The protection of the Kurds and the Marsh Arabs in the no-fly zones, for example, maintaining the defence of the Falkland Islands, looking after our interests around the world.
"I think there's a very good case to be made for all elements, whether it's helicopter transport aircraft, recce aircraft, all of that involved. I would say the Middle East, post-Cold War.
"Number one [is the RAF's ability] to deliver precision effects at range, at a time when nobody else could do it, and to destroy the great dams of the Ruhr.
"Today we wouldn't do that. Today we might even call it a war crime.
"But to do it with such effect, to tie up 70,000 German workers, including those who were supposed to be building the defences for D-Day, to cause the cost in today's terms of £86 billion...
"To stop production of tanks just before the Russian campaigns, to stop the production of the new aircraft the Focke-Wulf [Fw] 190 and to do it in such an innovative way... [means] the Dambusters get my vote as number one."
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