Second prototype of the YH-16 program. Crashed 1956 due to an mechanical failure of the instrumentation system of the aft main rotor.
A video of the aircraft can be viewed on the VHS YouTube site below,
Source: "Turbo Transporter': Huge Craft in FIrst Public Showing", Vertical Flight Society YouTube site, Published on 4 Mar 2012
VTOL type: Helicopter
Lift devices: 2 in Tandem (Fore/aft) configuration
Crew required: 3 in Side-by-side arrangement
Landing gear: Wheels (non-retractable)