The Douglas Aircraft Company constructed the Douglas D-558-2 Skyrocket (or D-558-II), a supersonic research aircraft that was powered by both rocket and jet engines, for the United States Navy.
On the 20th of November in 1953, just prior to the 50th anniversary of powered flight on the 17th of December, Scott Crossfield successfully piloted the Skyrocket to a speed of Mach 2, which equates to over 1,290 mph (2076 km/h).
This marked the first instance in which an aircraft had surpassed twice the speed of sound.
The aircraft’s designation included a “2” to indicate that the Skyrocket was the second phase of a three-phase program.
The initial phase, the D-558-1, was equipped with jet propulsion and straight wings.
The third phase, which was never realized, would have entailed constructing a mock-up of a combat aircraft that incorporated the findings from the testing of the first two phases.
The D-558-3 design, which was never constructed, was for a hypersonic aircraft that resembled the North American X-15.
When it became apparent that the D558-1 fuselage could not be modified to accommodate both rocket and jet power, the D558-2 was developed as a completely new aircraft.
On January 27, 1947, a contract change order was issued to formally abandon the final three D558-1 aircraft and replace them with three new D558-2 aircraft.
The Skyrocket featured wings with a 35-degree sweep and horizontal stabilizers with a 40-degree sweep.
The wings and empennage were constructed of aluminium, while the large fuselage was primarily made of magnesium.
The Skyrocket was powered by a Westinghouse J34-40 turbojet engine, which was fed through side intakes in the forward fuselage and intended for take-off, climb, and landing.
For high-speed flight, a four-chamber Reaction Motors LR8-RM-6 engine (the Navy designation for the Air Force’s XLR11 used in the Bell X-1) was installed.
This engine was rated at 6,000 lbf (27 kN) static thrust at sea level.
The fuselage tanks carried a total of 250 US gallons (950 L) of aviation fuel, 195 US gallons (740 L) of alcohol, and 180 US gallons (680 L) of liquid oxygen.
The Skyrocket was initially designed with a flush cockpit canopy, but the visibility from the cockpit was inadequate.
As a result, the cockpit was reconfigured with raised conventional angled windows, which increased the profile area at the front of the aircraft.
This was balanced by adding an additional 14 inches (36 cm) of height to the vertical stabilizer.
Similar to its predecessor, the D558-1, the D558-2 was designed so that the forward fuselage, including the cockpit, could be separated from the rest of the aircraft in an emergency.
Once the forward fuselage had decelerated sufficiently, the pilot could escape from the cockpit using a parachute. Skyrocket Aircraft Serial Numbers D-558-2 (1) 37973, NACA-143, 123 flights D-558-2 (2) 37974, NACA-144, 103 flights D-558-2 (3) 37975, NACA-145, 87 flights Specifications Crew 1 Length 42 ft (13 m) Wingspan 25 ft (7.6 m) Height 12 ft 8 in (3.86 m) Wing area 175 sq ft (16.3 m2) Airfoil Root NACA 63-010 Tip NACA 63-012 Launch weight turbojet only. 10,572 lb (4,795 kg) Launch weight mixed power. 15,266 lb (6,925 kg) Launch weight rocket only. 15,787 lb (7,161 kg) Fuel capacity Turbojet fuel capacity 250 US gal (210 imp gal; 950 L) Avgas Rocket fuel capacity 195 US gal (162 imp gal; 740 L) Alcohol Rocket oxidiser capacity 180 US gal (150 imp gal; 680 L) LOX Turbopump H2O2 capacity 11 US gal (9.2 imp gal; 42 L) High Test Hydrogen Peroxide (HTP) Powerplant 1 × Westinghouse J34-WE-40 turbojet engine, 3,000 lbf (13 kN) thrust. Powerplant 1 × Reaction Motors XLR8-RM-5, 4-chambered liquid-fuelled rocket engine, 6,000 lbf (27 kN) thrust. Performance Maximum speed 585 mph (941 km/h, 508 kn) at 20,000 ft (6,100 m)
On turbojet only 720 mph (630 kn; 1,160 km/h) at 40,000 ft (12,000 m)
On mixed power with conventional take-off 1,250 mph (1,090 kn; 2,010 km/h) at 67,500 ft (20,600 m) on rocket power air-launched Stall speed 160 mph (260 km/h, 140 kn) Rate of climb 22,400 ft/min (114 m/s) mixed power 11,100 ft/min (3,400 m/min) rocket power only Wing loading 60.4 lb/sq ft (295 kg/m2) turbojet engine only 87.2 lb/sq ft (426 kg/m2) mixed power 90.2 lb/sq ft (440 kg/m2) rocket engine only Sources McDonnell Douglas aircraft since 1920: Volume I-René J Francillon. San Diego Air and Space Museum Archive. The National Museum of the U.S. Air Force. X-Planes, Douglas D-558-D-558-1 Skystreak & D-558-2 Skyrocket-Peter E Davies, Adam Tooby.
