Battle Stations II
Lockheed
SR-71 Blackbird
Crew 2
Engines 2 x 32,500lb (14,742kg) thrust Pratt & Whitney
J58s continuous bleed after-burning turbojets of 32,500lb thrust
Dimensions Wingspan 55ft 7in (16.94m), wing
area 1,800sq ft (167.2sq m), length 107ft
5in (32.74m), height overall 18ft 6in
(5.64m)
Weight Empty not disclosed but about
65,000 lb (29,500kg), maximum about 170,000lb
(77,112kg)
Performance Maximum speed (also maximum
cruising speed) about 2,100mph (3,380kmh) at over 60,000ft (18,290m)
with world record speed over a 15-mile (25k) course of 2,193mph
(3,530kmh), maximum sustained height (also
world record) 85,069ft (25,900m), range (at
78,740ft/24,000m) at Mach 3
(1,983mph/3,191kmh) on internal fuel: 2,982 miles (4,800km)
Armament None
The SR-71, known as the 'Blackbird' because of its special heat-emitting paint, was developed by Lockheed as a long-range, advanced, strategic reconnaissance aircraft – in other words, a spy plane. It was derived from the smaller A-12 via the YF-12A long-range interceptor, neither of which saw service.
The SR-71 made its maiden flight on 22 December 1964 and entered service in the US Air Force with the 4200th (later 9th) Strategic Reconnaissance Wing at Beale air force base in California in January 1966. Throughout its career, it remained the world's fastest and highest-flying operational aircraft. It was also the most costly to operate, and every flight was planned like a space mission.
Its two-man crew – pilot and reconnaissance systems officer (RSO) – wore astronauts' suits and sat in separate tandem cockpits with roof hatches containing windows of heat-resistant glass. The greater part of the airframe was of aged B-120 titanium. Specially developed refrigeration systems kept the local temperature down. The SR-71's JP-7 kerosene fuel was supplied by a fleet of KC-135Q tankers, also based at Beale. This unique fuel iwa used as the 'sink' that absorbed all the enormous surplus heat loads throughout the aircraft.
The SR-71 programme comprised 31 aircraft, two of which were converted into trainers. All their missions, many of which were for the CIA, were clandestine and flown for maximum range and minimum radar and IR signature. The SR-71 was often sent to distant temporary operating locations for over-flights of territory that could not be reached from Beale.
The accessibility of the aircraft's cross-section to radar was reduced partly by its stealth-like shape and partly by the external paint surface, which incorporated billions of microscopic iron balls that produced a conductive film to reduce radar reflectivity.
At one point in its career, the SR-71 carried the Lockheed GTD-21 reconnaissance RPV (remote piloted vehicle) in a pick-a-back mount, releasing it for overflights of the most sensitive or dangerous targets. The SR-71 subsequently acted as the data-link platform for the digitised pictures and Elint (electronic intelligence) signals that the RPV sent back. The SR-71's top-secret sensors included spacecraft optical equipment – from 80,000ft (24,385m), it could survey 100,000 square miles of the Earth's surface every hour.
The USAF retired its fleet of SR-71s in January 1990 because of defence budget cuts and soaring operational costs. But in 1995, the Blackbird was returned to the active inventory, and operational missions were resumed from January 1997. This remarkable example of American high technology has since been retired.
