Comments by "Big Blue" (@bigblue6917) on "Neither Fish nor Fowl; The Blackburn B20, B40 and B44" video.

I remember reading about the Firebrand test firing its guns during WW2. As Blackburn's factory is right next to the River Humber there is a bank between it and the river to protect the factory from flooding. To test fire the four 20 mm cannons they would lift the Firebrand's tail up to get the aircraft level then, fire at a target which was in front of the bank. After test firing one day they got a message from a rather irate barge skipper complaining about being fired on from the factory as he sailed up the river. It turned out that they had fired at the same spot so often that the cannon shells had dug a hole through the bank.
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