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Come on, DV, you're not sticking your neck out far enough to give us speedboaters room to hang you! How about some specifics?
My thought on the Bluebird, then and now, was that Campbell had a nice 200-225mph boat (smooth water only), but that both the engine fairing and the tops of the sponsons had enough curve to create a lot of aerodynamic lift which could cause trouble given how light the boat was. He needed to spoil some of that lift, and he needed a way to make the lifting effect over the top of the boat be spoiled instantly whenever the bow started to rise. There is a way to do this. Imagine a standard light aircraft wing, say on a Cessna 150. This is designed to work across a good range of angles of attack until the stall. Now, if you were to attach a piece of stiff sheet aluminum, 8" wide and running from wingtip to wingtip, sticking straight forward into the airflow as the airplane is sitting on the ramp, you would have a pitch-spoiler. The plane could make its takeoff run, building lift over the wing, with no effect from the spoiler, which is parallel to the airflow. But when you start to rotate, increasing angle of attack, that 8" of sheetmetal is now at an angle to the airflow, which trips over its sharp edge, and goes turbulent before it gets to the wing . . . spoiling lift.
The one guy I knew who built some boats (outboard hydros) with this type of spoiler (thirty years ago) was Ron Anderson. Ron said the first version of this anti-blowover spoiler was TOO effective and made the boat excessively pitch-sensitive.
But I'm curious as to what YOU have in mind, DV. I hope its not yet another "backwards-boat." Over the years, many would-be improvers have looked at our three-point hydros, with the two sponsons and most of the aerodynamic lift apparently well forward, and seen them blow over backwards. And they said, "Why don't those fools have one step forward, and the two sponsons and all of the lift aft, lifting the weight of the engine, and they won't blow over?!!" And every fifteen years or so someone builds such a boat, and a driver dies when it stabs its pointy nose into a roller like a spear looking for a place to land. I've only seen a few old photos of the British "Crusader" of the early '50s, and don't know the name of the unfortunate pilot of that craft. But I've seen good home-movie footage of the Dave Karelsen bat-wing drag boat augering-in with the late Chuck Skaggs at the wheel. Ron Anderson was running some of the timing equipment when Lee Taylor was killed by his backwards boat. The "Circus Circus" unlimited hydro was abandoned before it killed anyone, but I stood in the pits in Seattle and watched it come by on a test run, all alone in the straightaway and in good water, when for no discernable reason it violently swapped ends. Driver Ron Armstrong, who was rather skeptical about the craft anyway, was heard breathing hard on his radio until he recovered enough to exclaim, "Holy Hell!!!!!"
But I'll just bet there is another "backwards-boat" on somebody's drawing board right now.
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