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The SB-1 Defiant has begun spinning rotors in West Palm Beach, Fla., where the Sikorsky [LMT]-Boeing [BA] team is readying the compound helicopter prototype for its first flight early this year. “The Sikorsky-Boeing SB>1 DEFIANT helicopter has completed its initial ground run and is currently advancing through the ground testing activity in the build up to first flight,” the joint venture told sister publication R&WI in an emailed statement. A video of Defiant spinning its coaxial rigid rotors while bolted…
