Before the US Army's ubiquitous workhorse transport/utility helicopter - the Sikorsky UH-60 "Black Hawk" - had become a household name, the "Black Hawk/Blackhawk" designation served a 1970s Sikorsky attack helicopter endeavor centered around its S-67 model. Of an advanced design for its time, the type was intended to fulfill the new US Army need for a dedicated, heavily armed and armored attack system capable of defeating Soviet armor at range while promoting excellent speeds and crew protection. Initial work began through a 1960s-era US Army initiative known as the Advanced Aerial Fire Support System (AAFSS) program to which Sikorsky submitted its S-66 design (with pivoting tail rotor acting as a "pusher" prop for increased cruise speeds) against the Lockheed CL-840 (to become the ill-fated AH-56 "Cheyenne"). The Lockheed design was eventually selected as the winner though the program was invariably delayed and ultimately cancelled through internal controversy and the AH-56's complicated/expensive nature.
When the AAFSS program ran into issues, Sikorsky went to work on a modified S-66 design, this becoming the S-67 model, with design work beginning in late 1969. The S-67 was conceived of as a dedicated attack helicopter in a primary role with the intention of carrying an assault-minded role as secondary. 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/transport helicopter offered by the Soviet Union during the Cold War (with many in service to this day - 2012).
Construction of a flyable prototype ensued in 1970 and a first flight as recorded on August 20th, 1970. On August 9th, 1972, the Lockheed AH-56 Cheyenne was formally cancelled and this pitted the S-67 against the Bell 309 "King Cobra" in a 1972 evaluation to replace the Cheyenne. However, neither design fit the US Army bid and both designs eventually fell to naught (such was the procurement process of the US Army at the time). This resulted in the US Army developing yet another new attack helicopter program known as the "Advanced Attack Helicopter" which finally produced the excellent Hughes AH-64 "Apache" tank-killing helicopter. The sole S-67 prototype existed as a company showpiece and developmental platform from then on before being lost to an accident.
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. Along the sides of the fuselage were sponsons which housed the retractable main undercarriage legs (the rear tail wheel did not retract). 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 (added later in the program) and advanced attack functionality. All told, 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 (TAT-140). The passenger crew compartment was buried within the lower main portion of the fuselage and insulated/soundproofed from the elements and engine noise.
The Sikorsky S-67 continued to be showcased through marketing endeavors for a short time. It managed to set world speed records in late December of 1970 and, in 1974, the US Army requested a ducted tail fan unit to be tested in the design. This provided the Blackhawk with a top speed of 230mph when evaluated though the helicopter was returned to its former form thereafter. The Blackhawk's tenure in the air ended poorly - and tragically - however when, during an acrobatic aerial presentation at the 1974 Farnborough Air Show, the sole S-67 prototype crashed into the ground. Pilot Stu Craig was killed on impact while pilot Kurt Cannon died nine days later. This signified an inglorious end to the promising S-67 design.
The Blackhawk name emerged once again after the US Army adoption of the Sikorsky S-70 design as the UH-60 "Black Hawk" of 1979.
- Ground Attack
- Close-Air Support (CAS)
- X-Plane / Developmental
74.15 ft (22.6 m)
62.01 ft (18.9 m)
14.99 ft (4.57 m)
12,522 lb (5,680 kg)
24,251 lb (11,000 kg)
193 mph (311 kph; 168 kts)
16,995 feet (5,180 m; 3.22 miles)
220 miles (354 km; 191 nm)
1 x 30mm cannon in nose turret
4x4 (16) x TOW anti-tank guided missiles (ATGM) OR 4x4 76 x 70mm 19-shot rocket pods on wing stubs.
2 x AIM-9 Sidewinder short-range air-to-air missiles on wing tips.
S-67 - Base Series Designation