Sikorsky introduced the S-67 Blackhawk in 1970, designed for infantry support and ground destruction missions.
The 1960s were a time of explosive growth in the helicopter industry, both civilian and military. Based on unpleasant experiences in the Vietnam battlefield, the US was looking for a turbine-powered armed attack helicopter to protect the Piasecki H-21 and Bell UH-1 Huey transport aircraft. Sikorsky introduced the S-67 Blackhawk in 1970, designed for infantry support and ground destruction missions. It is considered to be a good successor to the role of the AH-1, but the advantages of the Blackhawk were not enough and along with a serious accident, the S-67 project was permanently suspended.
By combining incredible speed and maneuverability with the ability to carry more than 7,000 pounds of firepower or up to eight fully armed soldiers, the S-67 attack helicopter was not only a powerhouse in its day, it would still be among the most capable attack helicopters on the planet if had ever entered service.
In the former, the helicopter would have been outfitted with various weaponry – cannon, rocket pods, anti-tank missiles and short-ranged air-to-air missiles for a variable array of mission types. In the latter, the aircraft would have ferried up to eight combat-ready troops into battle under the protection of the aforementioned armament. In this way, the Blackhawk would have largely served the same battlefield role as the more famous Mil MI-24 “Hind” attack helicopter offered by the Soviet Union during the Cold War.
Design of the S-67 incorporated a conventional large-diameter five-bladed main rotor assembly tied to a conventional five-bladed tail rotor facing portside. Power was derived from 2 x General Electric T58-GE-5 turboshaft engines, each delivering 1,500 shaft horsepower, supplying the aircraft with a top speed of 193 miles per hour, 220 mile range and a 20,000 foot service ceiling. The two pilots were seated in tandem along a slim-profile fuselage well-forward in the design.
Short wings were fitted at the sponson sides and these showcased trailing edge speed brakes which would aid in agility, allowing for quick turning and rapid slowing down. Internally, the cockpit was modernized with a large moving map display, night vision as standard and advanced attack functionality.
The S-67 would have been cleared to fire the then-standard TOW wire-guided anti-tank missile across four underwing hardpoints. Wingtips would have been reserved for carrying AIM-9 Sidewinder short-ranged air-to-air missiles for self-defense. The weapons array could be made more balanced through the integration of 70mm rocket pods. Up to 16 x TOW missiles could be carried in packs of four launchers each across the four provided underwing stations. Standard armament included a 30mm cannon housed in the advanced Tactical Armament Turret. The passenger crew compartment was buried within the lower main portion of the fuselage.
The S-67 Blackhawk, along with the Bell 309 KingCobra, was put through a series of flight test evaluations in 1972 by the U.S. Army. Neither aircraft was selected to replace the AH-56 Cheyenne. Instead, the Army chose to create the new Advanced Attack Helicopter program, which would lead to the AH-64 Apache several years later.
The S-67 performed a series of aerobatic maneuvers during its various marketing tours, including rolls, split-S, and loops. The S-67 was reputed to be very smooth and responsive, in spite of its size and speed. The lone S-67 prototype crashed while conducting a low-level aerobatic demonstration at the Farnborough Airshow on 1 September 1974. The United States Army later assigned the name Black Hawk to the Sikorsky UH-60 Black Hawk helicopter.