






The ABC (Advancing Blade Concept) was designed to prove the viability of two counter rotating main rotors on a common axis as a means of achieving higher speeds and better agility
Its simple design eliminates the tail rotor for anti-torque and directional control. Rudders
in the twin tail are used instead, as in a fixed-wing aircraft
The concept also offers lower operating and maintenance costs. The ABC has been extensively flight tested as a pure helicopter and, with auxiliary propulsion, flown at speeds in excess of 480 km/h
This system had the additional advantage of eliminating noise caused by the tail rotor and its transmission.
XH-59A serial number 73-21942.
The concept also offers lower operating and maintenance costs. The ABC has been extensively flight tested as a pure helicopter and, with auxiliary propulsion, flown at speeds in excess of 480 km/h
This system had the additional advantage of eliminating noise caused by the tail rotor and its transmission.
XH-59A serial number 73-21942.












The naval version of the Blackhawk, the SH-60B, designed as an anti submarine, anti surface-ship warfare system capable of operating from frigates and destroyers. Second naval variant is the SH-60F, CV-Helo, as the new aircraft-carrier-borne ASW helicopter, replacement of the S-61 Sea King.
