An animated video of the FVL proposal from Sikorsky appeared today. The Bell tilt-rotor V-280 proposal is proven, if expensive, technology. My biggest concern for the Sikorsky is the flex beam on the rotors. Until the new Huey/Cobras came out at 18,000 lbs, the Bell 412 (11,900 lbs) was the biggest helicopter I knew of with a rigid rotor and flex beams. Wonder if you can physically scale the flex beam up to something around 30,000 lbs? Hope the test pilots / engineers here might have some insights.