Lockheed SR-71 Blackbird

The Lockheed SR-71 "Blackbird" is a long-range, Mach 3+ strategic reconnaissance aircraft that was operated by the United States Air Force. It was developed as a black project from the Lockheed A-12 reconnaissance aircraft in the 1960s by Lockheed and its Skunk Works division. Renowned American aerospace engineer Clarence "Kelly" Johnson was responsible for many of the design's innovative concepts. During aerial reconnaissance missions, the SR-71 operated at high speeds and altitudes to allow it to outrace threats. If a surface-to-air missile launch was detected, the standard evasive action was simply to accelerate and outfly the missile. The SR-71 was designed to have basic stealth characteristics and served as a precursor to future stealth aircraft.

The SR-71 served with the U.S. Air Force from 1964 to 1998. A total of 32 aircraft were built; 12 were lost in accidents and none lost to enemy action. The SR-71 has been given several nicknames, including Blackbird and Habu. It has held the world record for the fastest air-breathing manned aircraft since 1976; this record was previously held by the related Lockheed YF-12

Lockheed SR-71 Blackbird
Class Aircraft
Type Reconnaissance
Manufacturer Lockheed Martin
Origin United States of America
Country Name Origin Year
United States of America 1964
Country Name Operational Year Retirement Year
United States of America 1966 1998 View
ManufacturerName Production From Production To Quantity
Lockheed Martin 32 View
Background

Lockheed's previous reconnaissance aircraft was the relatively slow U-2, designed for the Central Intelligence Agency (CIA). The 1960 downing of Francis Gary Powers's U-2 underscored the U-2's vulnerability and the need for faster reconnaissance aircraft. The CIA turned again to Kelly Johnson and Lockheed's Skunk Works, who developed the A-12 and would go on to build upon its design concepts for the SR-71.

The A-12 first flew at Groom Lake (Area 51), Nevada, on 25 April 1962. Thirteen were built; two variants were also developed, including three YF-12A interceptor prototypes, and two M-21 drone carrier variants. The aircraft was meant to be powered by the Pratt & Whitney J58 engine, but development ran over schedule, and it was equipped instead with the less powerful Pratt & Whitney J75. The J58s were retrofitted as they became available, and became the standard powerplant for all subsequent aircraft in the series (A-12, YF-12, M-21) as well as the SR-71. The A-12 flew missions over Vietnam and North Korea before its retirement in 1968. The program's cancellation was announced on 28 December 1966, due both to budget concerns and because of the forthcoming SR-71.

SR-71

The SR-71 designator is a continuation of the pre-1962 bomber series; the last aircraft built using the series was the XB-70 Valkyrie; however, a bomber variant of the Blackbird was briefly given the B-71 designator, which was retained when the type was changed to SR-71.

During the later period of its testing, the B-70 was proposed for a reconnaissance/strike role, with an RS-70 designation. When it was clear that the A-12 performance potential was much greater, the Air Force ordered a variant of the A-12 in December 1962. Originally named R-12 by Lockheed, the Air Force version was longer and heavier than the A-12, with a longer fuselage to hold more fuel, two seats in the cockpit, and reshaped chines. Reconnaissance equipment included signals intelligence sensors, a side looking airborne radar and a photo camera. The CIA's A-12 was a better photo reconnaissance platform than the Air Force's R-12, since the A-12 flew somewhat higher and faster, and with only one pilot it had room to carry a superior camera and more instruments.

During the 1964 campaign, Republican presidential nominee Barry Goldwater repeatedly criticized President Lyndon B. Johnson and his administration for falling behind the Soviet Union in developing new weapons. Johnson decided to counter this criticism by revealing the existence of the Lockheed YF-12A Air Force interceptor, which also served as cover for the still-secret A-12, and the Air Force reconnaissance model since July 1964. Air Force Chief of Staff General Curtis LeMay preferred the SR (Strategic Reconnaissance) designation and wanted the RS-71 to be named SR-71. Before the July speech, LeMay lobbied to modify Johnson's speech to read SR-71 instead of RS-71. The media transcript given to the press at the time still had the earlier RS-71 designation in places, creating the story that the president had misread the aircraft's designation.

In 1968, Secretary of Defense Robert McNamara canceled the F-12 interceptor program; the specialized tooling used to manufacture both the YF-12 and the SR-71 was also ordered destroyed. Production of the SR-71 totaled 32 aircraft with 29 SR-71As, 2 SR-71Bs, and the single SR-71C.

The SR-71 was designed for flight at over Mach 3 with a flight crew of two in tandem cockpits, with the pilot in the forward cockpit and the Reconnaissance Systems Officer (RSO) operating the surveillance systems and equipment from the rear cockpit, and directing navigation on the mission flight path. The SR-71 was designed to minimize its radar cross-section, an early attempt at stealth design. Finished aircraft were painted a dark blue, almost black, to increase the emission of internal heat and to act as camouflage against the night sky. The dark color led to the aircraft's nickname "Blackbird".

While the SR-71 carried radar countermeasures to evade interception efforts, its greatest protection was its high speed and cruising altitude that made it almost invulnerable. The aircraft's combination of high altitude and very high speed, along with its low radar cross-section, gave a very short amount of time for an enemy surface-to-air missile (SAM) site to acquire and track the aircraft on radar. By the time the SAM site could track the SR-71, it was often too late to launch a SAM, and the SR-71 would be out of range before the SAM could catch up to it. If the SAM site could track the SR-71 and fire a SAM in time, the SAM expended nearly all of the delta-v of its boost and sustainer phases just reaching the SR-71's altitude, and then, out of thrust, went ballistic. Merely accelerating would typically be enough to evade a SAM. Changes by the pilots in the SR-71's speed, altitude, and heading were often enough to spoil any radar lock on the plane by SAM sites or enemy fighters. At sustained speeds of Mach 3.2+, the plane was faster than the Soviet Union's fastest interceptor, the Mikoyan-Gurevich MiG-25, which also could not reach the SR-71's altitude. During its service life, no SR-71 was shot down.

Main era

The first flight of an SR-71 took place on 22 December 1964, at Air Force Plant 42 in Palmdale, California. The SR-71 reportedly reached a top speed of Mach 3.4 during flight testing. The first SR-71 to enter service was delivered to the 4200th (later, 9th) Strategic Reconnaissance Wing at Beale Air Force Base, California, in January 1966.

SR-71s first arrived at the 9th SRW's Operating Location (OL-8) at Kadena Air Base, Okinawa on 8 March 1968. These deployments were code named "Glowing Heat", while the program as a whole was code named "Senior Crown". Reconnaissance missions over North Vietnam were code named "Giant Scale". On 21 March 1968, Major (later General) Jerome F. O'Malley and Major Edward D. Payne flew the first operational SR-71 sortie in SR-71 serial number 61-7976 from Kadena AB, Okinawa. During its career, this aircraft (976) accumulated 2,981 flying hours and flew 942 total sorties (more than any other SR-71), including 257 operational missions, from Beale AFB; Palmdale, California; Kadena Air Base, Okinawa, Japan; and RAF Mildenhall, UK. The aircraft was flown to the National Museum of the United States Air Force near Dayton, Ohio in March 1990.

The Air Force could fly each SR-71, on average, once per week, because of the extended turnaround required after mission recovery. Very often an aircraft would return with rivets missing, delaminated panels or other broken parts such as inlets requiring repair or replacement. There were cases of the aircraft's not being ready to fly again for a month due to the repairs needed. Rob Vermeland, Lockheed Martin's manager of Advanced Development Program, said in an interview in 2015 that high-tempo operations were not realistic for the SR-71. "If we had one sitting in the hangar here and the crew chief was told there was a mission planned right now, then 19 hours later it would be safely ready to take off."

From the beginning of the Blackbird's reconnaissance missions over enemy territory (North Vietnam, Laos, etc.) in 1968, the SR-71s averaged approximately one sortie a week for nearly two years. By 1970, the SR-71s were averaging two sorties per week, and by 1972, they were flying nearly one sortie every day. Two SR-71s were lost during these missions, one in 1970 and the second aircraft in 1972, both due to mechanical malfunctions. Over the course of its reconnaissance missions during the Vietnam War, the North Vietnamese fired approximately 800 SAMs at SR-71s, none of which managed to score a hit.

While deployed in Okinawa, the SR-71s and their aircrew members gained the nickname Habu (as did the A-12s preceding them) after a pit viper indigenous to Japan, which the Okinawans thought the plane resembled.

Swedish Air Force fighter pilots, using the predictable patterns of SR-71 routine flights over the Baltic Sea, managed to lock their radar on the SR-71 on numerous occasions. Despite heavy jamming from the SR-71, target illumination was maintained by feeding target location from ground-based radars to the fire-control computer in the JA 37 Viggen interceptor. The most common site for the lock-on to occur was the thin stretch of international airspace between Öland and Gotland that the SR-71 used on the return flight. SAF observed via radar how a MiG-25 at 63,000 ft trailed 2.9 km behind the SR-71 at 72,000 ft.

Operational highlights for the entire Blackbird family (YF-12, A-12, and SR-71) as of about 1990 included:

  1.     3,551 mission sorties flown
  2.     17,300 total sorties flown
  3.     11,008 mission flight hours
  4.     53,490 total flight hours
  5.     2,752 hours Mach 3 time (missions)
  6.     11,675 hours Mach 3 time (total)

Only one crew member, Jim Zwayer, a Lockheed flight-test reconnaissance and navigation systems specialist, was killed in a flight accident. The rest of the crew members ejected safely or evacuated their aircraft on the ground.

Initial retirement

The SR-71 program's main operational capabilities came to a close at the end of fiscal year 1989 (October 1989). The 1st SRS kept its pilots and aircraft operational and active, and flew a limited number of operational reconnaissance missions through the end of 1989 and into 1990, due to uncertainty over the timing of the final termination of funding for the program. The squadron finally closed up in mid-1990, and the aircraft were distributed to static display locations, with a number kept in reserve storage.

The SR-71 program was terminated due to Pentagon politics, and not because the aircraft had become obsolete or irrelevant, or suffered maintenance problems, or had unsustainable program costs, although these reasons are frequently cited as justifications for its downfall. In the 1970s and early 1980s, SR-71 squadron and wing commanders were often promoted into higher positions as general officers within the Air Force structure and the Pentagon (in order to be selected into the SR-71 program in the first place, a pilot or navigator (RSO) had to be a top-quality Air Force officer, so continuing career progression for members of this elite group was not surprising). These generals were adept at communicating the value of the SR-71 to an Air Force command staff and a Congress who often lacked a basic understanding of how the SR-71 worked and what it did. However, by the mid-1980s, these SR-71 generals all had retired, and a new generation of Air Force generals wanted to cut the program's budget and spend its funding on new strategic bomber programs instead, especially the very expensive B-2 Spirit. The Air Force saw the SR-71 as a bargaining chip which could be sacrificed to ensure the survival of other priorities. Also, the SR-71 program's "product," which was operational and strategic intelligence, was not seen by these generals as being very valuable to the Air Force. The primary consumers of the intelligence produced by the SR-71 were the CIA, NSA, and DIA. It was believed by a former 1st SRS commander that if the SR-71 had been funded by an intelligence agency (like the A-12 was), instead of the Air Force, it would have easily survived.

A general misunderstanding of the nature of aerial reconnaissance and a lack of knowledge about the SR-71 in particular (due to its secretive development and operations) was used by detractors to discredit the aircraft, with the assurance given that a replacement was under development. Dick Cheney told the Senate Appropriations Committee that the SR-71 cost $85,000 per hour to operate. Opponents estimated a cost of $400 to $700 million per year to support the aircraft, even though the actual cost was closer to $300 million (compare this $300 million cost for the total annual operating expenditure for the entire SR-71 program to the $700 million to $1.2 billion cost of producing a single B-2 Spirit).

The SR-71, while much more capable than the Lockheed U-2 in terms of range, speed, and survivability, suffered the lack of a datalink, which the U-2 had been upgraded to carry. This meant that much of the SR-71's imagery and radar data could not be used in real time, but had to wait until the aircraft returned to base. This lack of immediate real-time capability was used as one of the justifications to close down the program. Attempts to add a datalink to the SR-71 were stymied early on by same factions in the Pentagon and Congress who were already set on the program's demise, even in the early 1980s. These same factions also forced expensive sensor upgrades upon the SR-71, which did little to increase its mission capabilities, but could be used as justification for complaining about the cost of the program.

In 1988, Congress was convinced to allocate $160,000 to keep six SR-71s (along with a trainer model) in flyable storage that could become flightworthy within 60 days; however, the USAF refused to spend the money. While the SR-71 survived attempts to retire it in 1988, partly due to the unmatched ability to provide high-quality coverage of the Kola Peninsula for the US Navy, the decision to retire the SR-71 from active duty came in 1989, with the last missions flown in October that year. Four months after the plane's retirement, General Norman Schwarzkopf, Jr., was told that the expedited reconnaissance, which the SR-71 could have provided, was unavailable during Operation Desert Storm.

Reactivation

    From the operator's perspective, what I need is something that will not give me just a spot in time but will give me a track of what is happening. When we are trying to find out if the Serbs are taking arms, moving tanks or artillery into Bosnia, we can get a picture of them stacked up on the Serbian side of the bridge. We do not know whether they then went on to move across that bridge. We need the  that a tactical, an SR-71, a U-2, or an unmanned vehicle of some sort, will give us, in addition to, not in replacement of, the ability of the satellites to go around and check not only that spot but a lot of other spots around the world for us. It is the integration of strategic and tactical.

    —?Response from Admiral Richard C. Macke to the Senate Committee on Armed Services.

Due to unease over political situations in the Middle East and North Korea, the U.S. Congress re-examined the SR-71 beginning in 1993. Rear Admiral Thomas F. Hall addressed the question of why the SR-71 was retired, saying it was under "the belief that, given the time delay associated with mounting a mission, conducting a reconnaissance, retrieving the data, processing it, and getting it out to a field commander, that you had a problem in timelines that was not going to meet the tactical requirements on the modern battlefield. And the determination was that if one could take advantage of technology and develop a system that could get that data back real time... that would be able to meet the unique requirements of the tactical commander." Hall stated they were "looking at alternative means of doing [the job of the SR-71].

Macke told the committee that they were "flying U-2s, RC-135s, other strategic and tactical assets" to collect information in some areas. Senator Robert Byrd and other Senators complained that the "better than" successor to the SR-71 had yet to be developed at the cost of the "good enough" serviceable aircraft. They maintained that, in a time of constrained military budgets, designing, building, and testing an aircraft with the same capabilities as the SR-71 would be impossible.

Congress' disappointment with the lack of a suitable replacement for the Blackbird was cited concerning whether to continue funding imaging sensors on the U-2. Congressional conferees stated the "experience with the SR-71 serves as a reminder of the pitfalls of failing to keep existing systems up-to-date and capable in the hope of acquiring other capabilities." It was agreed to add $100 million to the budget to return three SR-71s to service, but it was emphasized that this "would not prejudice support for long-endurance UAVs [such as the Global Hawk]." The funding was later cut to $72.5 million. The Skunk Works was able to return the aircraft to service under budget at $72 million.

Colonel Jay Murphy (USAF Retired) was made the Program Manager for Lockheed's reactivation plans. Retired Air Force Colonels Don Emmons and Barry MacKean were put under government contract to remake the plane's logistic and support structure. Still-active Air Force pilots and Reconnaissance Systems Officers (RSOs) who had worked with the aircraft were asked to volunteer to fly the reactivated planes. The aircraft was under the command and control of the 9th Reconnaissance Wing at Beale Air Force Base and flew out of a renovated hangar at Edwards Air Force Base. Modifications were made to provide a data-link with "near real-time" transmission of the Advanced Synthetic Aperture Radar's imagery to sites on the ground.

Final retirement

The reactivation met much resistance: the Air Force had not budgeted for the aircraft, and UAV developers worried that their programs would suffer if money was shifted to support the SR-71s. Also, with the allocation requiring yearly reaffirmation by Congress, long-term planning for the SR-71 was difficult. In 1996, the Air Force claimed that specific funding had not been authorized, and moved to ground the program. Congress reauthorized the funds, but, in October 1997, President Bill Clinton attempted to use the line-item veto to cancel the $39 million allocated for the SR-71. In June 1998, the U.S. Supreme Court ruled that the line-item veto was unconstitutional. All this left the SR-71's status uncertain until September 1998, when the Air Force called for the funds to be redistributed; the Air Force permanently retired it in 1998.

NASA operated the two last airworthy Blackbirds until 1999. All other Blackbirds have been moved to museums except for the two SR-71s and a few D-21 drones retained by the NASA Dryden Flight Research Center (later renamed the Armstrong Flight Research Center).

Timeline

1950s–1960s

  •     24 December 1957: First J58 engine run.
  •     1 May 1960: Francis Gary Powers is shot down in a Lockheed U-2 over the Soviet Union.
  •     13 June 1962: SR-71 mock-up reviewed by Air Force.
  •     30 July 1962: J58 completes pre-flight testing.
  •     28 December 1962: Lockheed signs contract to build six SR-71 aircraft.
  •     25 July 1964: President Johnson makes public announcement of SR-71.
  •     29 October 1964: SR-71 prototype (AF Ser. No. 61-7950) delivered to Air Force Plant 42 at Palmdale, California.
  •     7 December 1964: Beale AFB, CA, announced as base for SR-71.
  •     22 December 1964: First flight of the SR-71 with Lockheed test pilot Bob Gilliland at Air Force Plant #42.
  •     21 July 1967: Jim Watkins and Dave Dempster fly first international sortie in SR-71A, AF Ser. No. 61-7972, when the Astro-Inertial Navigation System (ANS) fails on a training mission and they accidentally fly into Mexican airspace.
  •     3 November 1967: A-12 and SR-71 conduct a reconnaissance fly-off. Results are questionable.
  •     5 February 1968: Lockheed ordered to destroy A-12, YF-12, and SR-71 tooling.
  •     8 March 1968: First SR-71A (AF Ser. No. 61-7978) arrives at Kadena AB, Okinawa to replace A-12s.
  •     21 March 1968: First SR-71 (AF Ser. No. 61-7976) operational mission flown from Kadena AB over Vietnam.
  •     29 May 1968: CMSgt Bill Gornik begins the tie-cutting tradition of Habu crews' neckties.

1970s–1980s

  •     3 December 1975: First flight of SR-71A (AF Ser. No. 61-7959) in "Big Tail" configuration.
  •     20 April 1976: TDY operations started at RAF Mildenhall, United Kingdom with SR-71A, AF Ser. No. 61-7972.
  •     27–28 July 1976: SR-71A sets speed and altitude records (Altitude in Horizontal Flight: 85,068.997 ft (25,929.030 m) and Speed Over a Straight Course: 2,193.167 miles per hour (3,529.560 km/h)).
  •     August 1980: Honeywell starts conversion of AFICS to DAFICS.
  •     15 January 1982: SR-71B, AF Ser. No. 61-7956, flies its 1,000th sortie.
  •     21 April 1989: SR-71, AF Ser. No. 61-7974, is lost due to an engine explosion after taking off from Kadena AB, the last Blackbird to be lost.[3][4]
  •     22 November 1989: Air Force SR-71 program officially terminated.

1990s

  •     6 March 1990: Last SR-71 flight under SENIOR CROWN program, setting four speed records en route to Smithsonian Institution.
  •     25 July 1991: SR-71B, AF Ser. No. 61-7956/NASA #831 officially delivered to NASA Dryden Flight Research Center at Edwards AFB, California.
  •     October 1991: NASA engineer Marta Bohn-Meyer becomes the first female SR-71 crew member.
  •     28 September 1994: Congress votes to allocate $100 million for reactivation of three SR-71s.
  •     28 June 1995: First reactivated SR-71 returns to Air Force as Detachment 2.
  •     9 October 1999: The last flight of the SR-71 (AF Ser. No. 61-7980/NASA 844).

Records

The SR-71 was the world's fastest and highest-flying operational manned aircraft throughout its career. On 28 July 1976, SR-71 serial number 61-7962, broke the world record: an "absolute altitude record" of 85,069 feet (25,929 m). Several aircraft have exceeded this altitude in zoom climbs, but not in sustained flight. That same day SR-71, serial number 61-7958, set an absolute speed record of 1,905.81 knots (2,193.2 mph; 3,529.6 km/h), approximately Mach 3.3. SR-71 pilot Brian Shul states in his book The Untouchables that he flew in excess of Mach 3.5 on 15 April 1986 over Libya to evade a missile.

The SR-71 also holds the "Speed Over a Recognized Course" record for flying from New York to London—distance 3,461.53 miles (5,570.79 km), 1,806.964 miles per hour (2,908.027 km/h), and an elapsed time of 1 hour 54 minutes and 56.4 seconds—set on 1 September 1974 while flown by U.S. Air Force Pilot Maj. James V. Sullivan and Maj. Noel F. Widdifield, reconnaissance systems officer (RSO). This equates to an average velocity of about Mach 2.72, including deceleration for in-flight refueling. Peak speeds during this flight were likely closer to the declassified top speed of Mach 3.2+. For comparison, the best commercial Concorde flight time was 2 hours 52 minutes and the Boeing 747 averages 6 hours 15 minutes.

On 26 April 1971, 61-7968, flown by Majors Thomas B. Estes and Dewain C. Vick, flew over 15,000 miles (24,000 km) in 10 hrs. 30 min. This flight was awarded the 1971 Mackay Trophy for the "most meritorious flight of the year" and the 1972 Harmon Trophy for "most outstanding international achievement in the art/science of aeronautics".

When the SR-71 was retired in 1990, one Blackbird was flown from its birthplace at United States Air Force Plant 42 in Palmdale, California, to go on exhibit at what is now the Smithsonian Institution's Steven F. Udvar-Hazy Center in Chantilly, Virginia. On 6 March 1990, Lt. Col. Raymond E. "Ed" Yielding and Lt. Col. Joseph T. "JT" Vida piloted SR-71 S/N 61-7972 on its final Senior Crown flight and set four new speed records in the process.

    Los Angeles, CA, to Washington, D.C., distance 2,299.7 miles (3,701.0 km), average speed 2,144.8 miles per hour (3,451.7 km/h), and an elapsed time of 64 minutes 20 seconds.

    West Coast to East Coast, distance 2,404 miles (3,869 km), average speed 2,124.5 miles per hour (3,419.1 km/h), and an elapsed time of 67 minutes 54 seconds.

    Kansas City, Missouri, to Washington, D.C., distance 942 miles (1,516 km), average speed 2,176 miles per hour (3,502 km/h), and an elapsed time of 25 minutes 59 seconds.

    St. Louis, Missouri, to Cincinnati, Ohio, distance 311.4 miles (501.1 km), average speed 2,189.9 miles per hour (3,524.3 km/h), and an elapsed time of 8 minutes 32 seconds.

These four speed records were accepted by the National Aeronautic Association (NAA), the recognized body for aviation records in the United States.Additionally, Air & Space reported that the Air Force clocked the Blackbird at one point in its flight reaching 2,242.48 mph. After the Los Angeles–Washington flight, Senator John Glenn addressed the United States Senate, chastening the Department of Defense for not using the SR-71 to its full potential:

    Mr. President, the termination of the SR-71 was a grave mistake and could place our nation at a serious disadvantage in the event of a future crisis. Yesterday's historic transcontinental flight was a sad memorial to our short-sighted policy in strategic aerial reconnaissance.

    —?Senator John Glenn, 7 March 1990

Successor

Speculation existed regarding a replacement for the SR-71, most notably a rumored aircraft codenamed Aurora. The limitations of reconnaissance satellites, which take up to 24 hours to arrive in the proper orbit to photograph a particular target, makes them slower to respond to demand than reconnaissance planes. The fly-over orbit of spy satellites may also be predicted and can allow assets to be hidden when the satellite is above, a drawback not shared by aircraft. Thus, there are doubts that the US has abandoned the concept of spy planes to complement reconnaissance satellites. Unmanned aerial vehicles (UAVs) are also used for much aerial reconnaissance in the 21st century, being able to overfly hostile territory without putting human pilots at risk, as well as being smaller and harder to detect than man-carrying aircraft.

On 1 November 2013, media outlets reported that Skunk Works has been working on an unmanned reconnaissance airplane it has named SR-72, which would fly twice as fast at Mach 6. However, the Air Force is officially pursuing the Northrop Grumman RQ-180 UAV to take up the SR-71's strategic ISR role.

RoleStrategic reconnaissance aircraft
ManufacturerLockheed, Skunk Works division
DesignerClarence "Kelly" Johnson
First flight22 December 1964
Introduction1966
Retired1998 (USAF), 1999 (NASA)
StatusRetired
Primary usersUnited States Air Force
NASA
Number built32
Unit cost$34 million
Developed fromLockheed A-12


General characteristics

  • Crew: 2
  • Payload: 3,500 lb (1,600kg) of sensors
  • Length: 107 ft 5 in (32.74m)
  • Wingspan: 55 ft 7 in (16.94m)
  • Height: 18 ft 6 in (5.64m)
  • Wing area: 1,800 ft2 (170m2)
  • Empty weight: 67,500 lb (30,600kg)
  • Loaded weight: 170,000 lb (77,000kg)
  • Max takeoff weight: 172,000 lb (78,000kg)
  • Powerplant: 2 x Pratt & Whitney J58-1 continuous-bleed afterburning turbojets, 32,500 lbf (145kN) each
  • Wheel track: 16 ft 8 in (5.08m)
  • Wheel base: 37 ft 10 in (11.53m)
  • Aspect ratio: 1.7

Performance

  • Maximum speed: Mach 3.2+ (2,200+ mph, 3,530+ km/h) at 80,000 ft (24,000 m)
  • Range: 2,900 nmi (5,400km)
  • Ferry range: 3,200 nmi (5,925 km)
  • Service ceiling 85,000 ft (25,900 m)
  • Rate of climb: 11,810 ft/min (60m/s)
  • Wing loading: 94 lb/ft2 (460kg/m2)
  • Thrust/weight: 0.382

End notes