There were wind tunnel and model tests done during the orignial design of Bluebird in 1953-54. The first tests of the boat in Ullswater however showed flaws in the design that required the repositioning of the front spar supporting the sponsons. Further modifications were carried out in refairing the upper sponsons (around 58 I believe), the first tail fin (around the same time) and the prespex bubble canopy. Wherever these were wind tested, I don't know. The final modification included the high tail, the Orpheus engine replacing the Breyl and the water brake. Where they wind tested? Possibly but Campbell was skint at this time. The K7 had a design speed of 250 MPH when it was built. Personally, My opinion is that the combination of wake from the first run and no down thrust from the fuel staved engine allowed the pitching moment of the boat to exceed the alpha that the nose could reach without taking off.. The boat was on its absolute limit even if campbell had refuelled and allowed his wake to die down.. He would have been bankrupted anyway afterwards as the tax man was after him..