As exciting as that was, there's no time for laurel resting. We immediately turned our attention to the water.
99 problems and flotation IS one
The race has a water obstacle. We have to roll into the water and climb a steep beach to get out. All of that and staying above the water require flotation. Last year, we used foam to float the Falcon (theoretically; we didn't actually make it to the water). I didn't like how much the foam obscured the guts of the sculpture.
The mechanics are just as much art as the aesthetics. The veteran builders typically use inflatable pontoons; we decided to follow their lead. Andee sourced a very large inflatable raft with a 660lb weight capacity. It's longer than the truss and not too wide. I thought it would work but to test it, we would have to ruin it as a raft.
The idea was that the front of the raft would support the heaviest part of the Falcon while the side pontoons would support the pilots. To make it more stable, we would spread the back of the pontoons out to create a 'V' shape. To do that meant cutting out the back and most of the bottom of the raft. At least this would also remove some dead weight.
The test was straightforward. Inflate the raft with the Falcon on top, then climb on and see how far we sink.
Everything went well. Because the raft was longer than the Falcon's frame, we were able to add supports at the middle and rear of the raft. This made it very stable, front to back. It easily handled the Falcon's weight, barely submerging into the water.
We didn't spread out the pontoons for this test, so it was unstable laterally. We are confident that spreading out the back of the side pontoons will solve that issue. However, there was another issue that now needed addressing.
The raft sits under the main truss frame and is very tall. Because of the way the wheels are attached, they do not touch the ground when the raft is inflated. This is a problem because we have to roll into and pedal out of the water during the race. To solve it, we must lower the wheels 10-12 inches. And that requires upgrades (read redesign) to the front suspension. No pressure.
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