The U. S. National Transportation Safety Board has published a report into the accident that affected a S-97 helicopter in August 2017.
While the manufacturer said the helicopter had a hard landing. The report reveals extensive damage to the coaxial rotors.
The NTSB says flight control laws introduced into the fly-by-wire system affected ground-to-air transitions of the rotorcraft.
The helicopter rolled left and right immediately after lift off from the ground. The roll caused both rotors to make contact and ripped off the tips of all eight blades. The pilot landed immediately but the landing gear collapsed which resulted in damages to the rear propeller.