My research into the Marine Aircraft Experimental Establishment, Helensburgh, continues to steer me into unchartered waters. I have a list of vessels used by the marine section circa 1942/45. Two vessels I would like to know more about. The Brooke Marine seaplane tender as used on Loch Lomond? While I know the history of Pemberton Billling speed boats, the notes attached to the one tested at Helensburgh intrigues me. This experimental MTB was fitted with twin Kestrel engines steered by contra-rotating props at each end. This must have been a one off? robin bird