Henstridge
The reason Henstridge (HMS Dipper from memory) had 5 runways was that it was built by the Royal Navy for the training of Seafire pilot's.
The Idea was that with 5 runways that there would allways be a runway facing into wind - so flying could allways take place as oon a a/c carrier when they turn into wind.
The Runways were also marked out with the exact dimensions of a a/c carrier - so that the pilot's could practice landing within the confines of a carrier deck.
The only reason i know this about Henstridge is that my late Grandmother was stationed there with WREN's where she was a Chief Petty Officer.
Hope this all help's.
brgds
W.G