The Lockheed SR-71 "Blackbird" was an advanced, long-range, Mach 3+ strategic reconnaissance aircraft.[1] It was developed as a black project from the Lockheed A-12 reconnaissance aircraft in the 1960s by the Lockheed Skunk Works. Clarence "Kelly" Johnson was responsible for many of the design's innovative concepts. During 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 outrun the missile.[2]
The SR-71 served with the U.S. Air Force from 1964 to 1998. Of the 32 aircraft built, 12 were destroyed in accidents, and none was lost to enemy action.[3][4] The SR-71 has been given several nicknames, including Blackbird and Habu, the latter in reference to an Okinawan species of pit viper.[5] Since 1976, it has held the world record for the fastest air-breathing manned aircraft, a record previously held by the YF-12.[6][7][8]
Lockheed's previous reconnaissance aircraft was the U-2, which was designed for the Central Intelligence Agency (CIA). In 1960, while overflying the USSR, the U-2 flown by Francis Gary Powers was shot down by Soviet surface-to-air missiles (SAMs). This highlighted the U-2's vulnerability due to its relatively low speed, and paved the way for the Lockheed A-12, also designed for the CIA by Clarence Johnson at Lockheed's Skunk Works.[9] The A-12 was the precursor of the SR-71. The A-12's first flight took place at Groom Lake (Area 51), Nevada, on 25 April 1962. It was equipped with the less powerful Pratt & Whitney J75 engines due to protracted development of the intended Pratt & Whitney J58. 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 follow-on SR-71 aircraft.
Thirteen A-12s were built. Two A-12 variants were also developed, including three YF-12A interceptor prototypes, and two M-21 drone carrier variants. The cancellation of A-12 program was announced on 28 December 1966,[10] due to budget concerns,[11] and because of the forthcoming SR-71. The A-12 flew missions over Vietnam and North Korea before its retirement in 1968.
The SR-71 designator is a continuation of the pre-1962 bomber series, which ended with the XB-70 Valkyrie. 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.[12] Originally named R-12[N 1] 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 radar and a photo camera.[12] 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,[11] and with only one pilot it had room to carry a superior camera[11] and more instruments.[13]
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 YF-12A Air Force interceptor, which also served as cover for the still-secret A-12,[14] 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.[15][N 2]
Production of the SR-71 totaled 32 aircraft with 29 SR-71As, 2 SR-71Bs, and the single SR-71C.[16]
The flight instrumentation of SR-71 Blackbird
The SR-71 was designed to minimize its radar cross-section, an early attempt at stealth design.[17]
The high temperatures generated by Mach 3 flight required its airframe to be made mostly of titanium. To control costs, Lockheed used a more easily worked alloy of titanium which softened at a lower temperature.[18]
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 call sign "Blackbird".
The air inlets had to be designed to allow for cruising at over Mach 3.2, yet keep air flowing into the engines at the initial subsonic speeds. At the front of each inlet was a sharply-pointed movable cone called a "spike" that was locked in its full forward position on the ground and during subsonic flight. As the aircraft accelerated past Mach 1.6, an internal jackscrew withdrew the spike as much as 26 inches (66 cm) inwards;[19] an analogue air inlet computer, based on pitot-static, pitch, roll, yaw, and angle-of-attack inputs, would determine how much movement was required. By moving, the spike tip would withdraw the shock wave, riding on it closer to the inlet cowling until it just touched slightly inside the cowling lip. In this position shock-wave spillage, causing turbulence over the outer nacelle and wing, was minimized while the spike shock-wave repeatedly reflected between the spike centerbody and the inlet inner cowl sides. In doing so, shock pressures were maintained while slowing the air until a Mach 1 shock wave formed in front of the engine compressor.[20]
Operation of the air inlets and air flow patterns through the J58
The backside of this "normal" shock wave was subsonic air for ingestion into the engine compressor. This capture of the Mach 1 shock wave within the inlet was called "Starting the Inlet". Tremendous pressures would be built up inside the inlet and in front of the compressor face. Bleed tubes and bypass doors were designed into the inlet and engine nacelles to handle some of this pressure and to position the final shock to allow the inlet to remain "started". Air that is compressed by the inlet/shockwave interaction is diverted directly into the afterburner to be mixed and burned. This configuration is essentially a ramjet and provides up to 70% of the aircraft's thrust at higher mach numbers.[citation needed] Ben Rich, the Skunkworks designer of the inlets, often referred to the engine compressors as "pumps to keep the inlets alive" and sized the inlets for Mach 3.2 cruise, the aircraft's most efficient speed.[21] The additional thrust refers to the reduction of engine power required to compress the airflow; the SR-71 was more fuel-efficient at higher speeds, in terms of pounds burned per nautical mile traveled. In one incident, SR-71 pilot Brian Shul conducted a mission where he had to maintain a higher than normal speed for some time in order to avoid multiple interception attempts; afterwards it was discovered that this had reduced their fuel consumption.[22]
In the early years of operation, the analog computers would not always keep up with rapidly changing flight environmental inputs. If internal pressures became too great and the spike was incorrectly positioned, the shock wave would suddenly blow out the front of the inlet, called an "Inlet Unstart." During an unstart, air flow through the engine compressor immediately stopped, thrust dropped, and exhaust gas temperatures rose. The remaining engine's asymmetrical thrust would cause the aircraft to yaw violently to one side during an unstart. SAS, autopilot, and manual control inputs would fight the yawing, but often the extreme off-angle would reduce airflow in the opposite engine and stimulate "sympathetic stalls". This generated a rapid counter-yawing, often coupled with loud "banging" noises and a rough ride, crews' helmets would sometimes strike their cockpit canopies until the violent motions subsided.[23] One practiced response to an inlet unstart was a pilot-commanded unstart of both inlets to prevent yawing, prior to the restart of both inlets.[24] Lockheed implemented an electronic control to detect unstart conditions and perform this reset action without pilot intervention.[25] Beginning in 1980, the analog inlet control system was replaced by a digital system, which prevented and reduced unstart instances.[26]
On most aircraft, use of titanium was limited by the costs involved in procurement and manufacture. It was generally used only in components exposed to the highest temperatures, such as exhaust fairings and the leading edges of wings. On the SR-71, titanium was used for 85% of the structure, with the rest of composite materials. As such, the SR-71 was a ground-breaking aircraft, and some of the fabrication methods employed by Lockheed have since been used in the manufacture of many jet fighters and other aircraft. Titanium requires distilled water to be used during welding, because the chlorine in tap water causes corrosion; similarly, the cadmium-plated tools used on other aircraft were also found to cause corrosion, and had to be replaced.[27] Metallurgical contamination was another problem; at one point, it caused the rejection of 80% of the titanium delivered for the project.[28][29]
The high temperatures generated during flight required special design and operating techniques. For example, major portions of the skin of the inboard wings were corrugated, not smooth. (Aerodynamicists initially opposed the concept and accused the design engineers of trying to make a Mach-3 variant of the 1920s-era Ford Trimotor, known for its corrugated aluminum skin.[21]) The heat of flight would have caused a smooth skin to split or curl, but the corrugated skin could expand vertically and horizontally. The corrugation also increased longitudinal strength. Similarly, the fuselage panels were manufactured to fit only loosely on the ground. Proper alignment was only achieved when the airframe heated up and expanded several inches. Because of this, and the lack of a fuel sealing system that could handle the thermal expansion of the airframe at extreme temperatures, the aircraft would leak JP-7 jet fuel on the runway. At the beginning of each mission, the aircraft would make a short sprint after takeoff to warm up the airframe, then refuel before heading off to its destination.
Cooling was carried out by cycling fuel behind the titanium surfaces in the chines. On landing, the canopy temperature was over 300 °C (572 °F).[21]
Studies of the aircraft's titanium skin revealed that the metal was actually growing stronger over time, because of intense heating caused by compression of the air at high speeds acting as a regular heat treatment.[citation needed]
The red stripes on some SR-71s are to prevent maintenance workers from damaging the skin. The curved skin near the fuselage's center is thin and delicate; there is no support underneath except for the widely spaced structural ribs.[citation needed] Non-fibrous asbestos with high heat tolerance was used in high-temperature areas.[citation needed]
The SR-71 was the first operational aircraft designed around a stealthy shape and materials. There were a number of features in the SR-71 that were designed to reduce its radar signature. The first studies in radar stealth technology seemed to indicate that a shape with flattened, tapering sides would reflect most radar energy away from the radar beams' place of origin. To this end, engineers suggested the addition of chines and an inward canting of the vertical control surfaces. Special radar-absorbing materials were incorporated into sawtooth shaped sections of the aircraft's skin, as well as cesium-based fuel additives to reduce the visibility exhaust plumes to radar. However, the SR-71 was still easily detected on radar while traveling at speed due to its large high-temperature exhaust stream. The SR-71 had a radar cross section (RCS) of around 10 square meters,[30] much greater than the later Lockheed F-117 Nighthawk, which had an RCS equivalent in size to a ball bearing.[31]
Rich's team showed that the radar return was reduced, Kelly Johnson later conceded that Russian radar technology advanced faster than the "anti-radar" technology employed against it.[32] Although equipped with a suite of electronic countermeasures, the SR-71's greatest protection was its top speed, making it almost invulnerable to the era's weapons technologies. In its service life, no SR-71 was shot down, despite attempts to do so. It flew too fast and too high for surface-to-air missile systems and was faster than the Soviet Union's principal interceptor, the MiG-25.[33] Accelerating would typically be enough to evade a missile fired against an SR-71.[2]
The SR-71 featured chines, a pair of sharp edges leading aft from either side of the nose along the fuselage. These were not a feature on the early A-3 design; Dr. Frank Rodgers, of the Scientific Engineering Institute (a CIA front company), had discovered that a cross-section of a sphere had a greatly reduced radar reflection, and adapted a cylindrical-shaped fuselage by stretching out the sides of the fuselage.[34] After the advisory panel provisionally selected Convair's FISH design over the A-3 on the basis of RCS, Lockheed adopted chines for its A-4 through A-6 designs.[35] When the Blackbird was being designed, no other airplane had featured chines, and Lockheed's engineers had to solve problems related to the differences in stability and balance caused by these unusual surfaces.[citation needed] Chines remain an important design feature of many of the newest stealth UAVs, such as the Dark Star, Bird of Prey, X-45 and X-47, since they allow for tail-less stability as well as for stealth.[citation needed]
Aerodynamicists discovered that the chines generated powerful vortices and created additional lift, leading to unexpected aerodynamic performance improvements.[36] The angle of incidence of the delta wings could then be reduced for greater stability and less drag at high speeds; more weight, such as fuel, could be carried to increase range. Landing speeds were also reduced, since the chines' vortices created turbulent flow over the wings at high angles of attack, making it harder for the wings to stall. High-alpha turns were limited by the capability of the engine inlets to ingest air, possibly resulting in flame out.[37] Pilots were thus warned not to pull more than 3 g and to avoid high angles of attack. The chines also acted like the leading edge extensions that increase the agility of modern fighters such as the F-5, F-16, F/A-18, MiG-29 and Su-27. The addition of chines also enabled the removal of the planned canard foreplanes.[N 3][38][39]
Water vapor is condensed by the low-pressure vortices generated by the chines outboard of each engine inlet.
Several exotic fuels were investigated for the Blackbird. Development began on a coal slurry powerplant, but Johnson determined that the coal particles damaged important engine components.[21] Research was conducted on a liquid hydrogen powerplant, however the tanks for storing cryogenic hydrogen were not of a suitable size or shape.[21] In practice, the Blackbird would burn somewhat conventional JP-7 jet fuel, however it was an unusual mixture composed primarily of hydrocarbons, also included alkanes, cycloalkanes, alkylbenzenes, indanes/tetralins, and naphthalenes.[citation needed] Fluorocarbons were present to increase its lubricity, an oxidizing agent to enable it to burn in the engines, and a cesium compound, A-50, to disguise the exhaust's radar signature.[citation needed]
The aircraft was prone to minor fuel leaks while on the ground. While slippery, it was not an urgent fire hazard as JP-7 had a relatively high flash point (140 °F, 60 °C). This also allowed its use as a coolant and hydraulic fluid in the SR-71.[citation needed] JP-7 was extremely difficult to light. To start the engines, triethylborane (TEB), which ignites on contact with air, was injected to produce temperatures high enough to ignite the JP-7. The TEB produced a characteristic green flame that can often be seen during engine ignition.[22] TEB was also used to ignite the afterburners. The aircraft carried 20 fluid ounces (600 ml) of TEB per engine, enough for at least 16 injections.[citation needed]
The cabin could be pressurized to an altitude of 10,000 ft (3,000 m) or 26,000 ft (7,900 m) during flight.[40] Crews flying a low-subsonic flight (such as a ferry mission) could wear standard USAF hard-hat helmets, pressure demand oxygen masks and Nomex flying suits.[citation needed]
But crews flying at 80,000 ft (24,000 m) could not use standard masks, which could not provide enough oxygen above 43,000 ft (13,000 m); moreover, the difference in air pressure between the cockpit and the space inside the mask would make exhalation extremely difficult. Furthermore, an emergency ejection at Mach 3.2 would subject crews to an instant heat rise of about 450 °F (230 °C).
To solve these problems, the David Clark Company produced protective pressurised suits for the A-12, YF-12, M-21 and SR-71 aircraft. Similar suits were used on the Space Shuttle.[citation needed] If a crew member had to bail out at high altitude, his suit's onboard oxygen supply would keep it pressurized. The crew member would freefall, allowing heat to bleed off, until the main parachute was opened at 15,000 ft (4,600 m). To test the suits, crew members would undergo explosive decompression in an altitude chamber at 78,000 ft (24,000 m) or higher while heaters would be turned on to 450 °F (230 °C), gradually decreasing at the expected rate in free-fall.[citation needed]
The cabin itself needed a heavy-duty cooling system, for cruising at Mach 3.2 would heat the aircraft's external surface well beyond 500 °F (260 °C)[41] and the inside of the windshield to 250 °F (120 °C). An air conditioner used a heat exchanger to dump heat from the cockpit into the fuel prior to the combustion.[citation needed]
The Blackbird's Pratt & Whitney J58-P4 engines were innovative marvels that used the most extreme materials of their time. Each J58 could produce 32,500 lbf (145 kN) of static thrust.[42] The only American engines designed to operate continuously on afterburner, the J58 engines were most efficient around Mach 3.2,[43][44] and this was the Blackbird's typical cruising speed.
A unique hybrid, the engine can be thought of as a turbojet inside a ramjet. At lower speeds, the turbojet provided most of the compression and most of the energy from fuel combustion. At higher speeds, the turbojet largely ceased to provide thrust; instead, air was compressed by the shock cones and fuel burned in the afterburner.
In detail, air was initially compressed (and thus also heated) by the shock cones, which generated shock waves that slowed the air down to subsonic speeds relative to the engine. The air then passed through four compressor stages and was split by movable vanes: some of the air entered the compressor fans ("core-flow" air), while the rest of the air went straight to the afterburner (via six bypass tubes). The air traveling through the turbojet was further compressed (and further heated), and then fuel was added to it in the combustion chamber: it then reached the maximum temperature anywhere in the Blackbird, just low enough to keep the turbine blades from softening. After passing through the turbine (and thus being cooled somewhat), the core-flow air went through the afterburner and met with any bypass air.
Around Mach 3, the increased heating from the shock cone compression, plus the heating from the compressor fans, was enough to get the core air to high temperatures, and little fuel could be added in the combustion chamber without melting the turbine blades. This meant the whole compressor-combustor-turbine set-up in the core of the engine provided less power, and the Blackbird flew predominantly on air bypassed straight to the afterburners, forming a large ramjet effect.[21][45][46] The maximum speed was limited by the specific maximum temperature for the compressor inlet of 800 °F (427 °C).
Early 1990s studies of inlets of this type indicated that newer technology could allow for inlet speeds with a lower limit of Mach 6.[47]
Originally, the Blackbird's engines started up with the assistance of an external engine referred to as a "start cart". The cart included two Buick Wildcat V8 engines positioned underneath the aircraft. The two engines powered a single, vertical driveshaft connecting to a single J58 engine. Once one engine was started, the cart was wheeled to the other side of the aircraft to start the other engine. The operation was deafening. Later, big-block Chevrolet engines were used. Eventually, a quieter, pneumatic start system was developed for use at Blackbird main operating bases, but the start carts remained to support recovery team Blackbird starts at diversion landing sites not equipped to start J-58 engines.[48]
Prior to the advent of the Global Positioning System (GPS) for navigation, the SR-71 required a precision navigation system for maintaining route accuracy and target tracking at very high speeds. Inertial navigation systems had been employed by the U-2 and A-12, but USAF planners wanted a system not vulnerable to inertial position error accumulation that would limit mission lengths.[citation needed] An astro-inertial navigation system (ANS) was devised that could correct inertial orientation errors with celestial observations. Nortronics, Northrop's electronics development organization, had in the mid-1950s developed an ANS for the SM-62 Snark missile and a separate system for the AGM-48 Skybolt missile. Following Skybolt's cancellation in December 1962, work began on adapting this system for the SR-71's use.[citation needed]
The ANS was located behind the Reconnaissance Systems Officer (RSO)'s position, tracking stars through a circular window set in the upper fuselage.[22] A time-consuming primary alignment was performed on the ground to bring the inertial components to a high degree of accuracy prior to takeoff. In flight, a "blue light" source star tracker, able to see stars during day and night time, would continuously track a variety of stars as the aircraft's changing position brought them into view. The system's digital computer ephemeris contained data on 56 (later 61) stars.[49] The ANS could supply attitude and position inputs to flight controls and other systems, including the Mission Data Recorder, Auto-Nav steering to preset destination points, automatic pointing and control of cameras and sensors, and optical or SLR sighting of fix points loaded into the ANS before takeoff.[50]
The SR-71 Defensive System B
The SR-71 originally included optical/infrared imagery systems; side-looking airborne radar (SLAR); electronic intelligence (ELINT) gathering systems; defensive systems for countering missile and airborne fighters; and recorders for SLAR, ELINT and maintenance data.[citation needed] The SR-71 carried a Fairchild tracking camera and an HRB Singer infrared camera, both of which ran during the entire mission for route documentation, to respond to any accusations of overflight.[citation needed]
Because the SR-71 carried an observer behind the pilot, it could not use the A-12's principal sensor, a single large-focal-length optical camera that sat in the "Q-Bay" behind the cockpit. Instead, camera systems could be located either in the wing chines or the aircraft's interchangeable nose. Wide-area imaging was provided by two of Itek's Operational Objective Cameras (OOCs), which provided stereo imagery across the width of the flight track, or an Itek Optical Bar Camera (OBC), which gave continuous horizon-to horizon coverage. A closer view of the target area was given by the HYCON Technical Objective Camera (TEOC), that could be directed up to 45 degrees left or right of the centerline.[51] Initially, the TEOCs could not match the resolution of the A-12's larger camera, but rapidly-made improvements in both the camera and film improved this performance.[51][52]
Side-looking radar, built by Goodyear Aerospace, could be carried in the removable nose. In later life the radar was replaced by Loral's Advanced Synthetic Aperture Radar System (ASARS-1). Both the first SLR and ASARS-1 were ground mapping imaging systems, collecting data either in fixed swaths left or right of centerline or from a spot location for higher resolution.[51] ELINT-gathering systems, called the Electro Magnetic Reconnaissance System (EMR), built by AIL could be carried in the chine bays to analyse electronic signal fields being passed through, and were pre-programmed to identify items of interest.[51][53]
Over its operational life, the Blackbird carried various electronic countermeasures, including warning and active electronic systems built by several ECM companies and called Systems A, A2, A2C, B, C, C2, E, G, H and M. On a given mission, an aircraft would carry several of these frequency/purpose payloads to meet the expected threats.[citation needed] After landing, recording systems and gathered information from the SLR and ELINT systems, and the Maintenance Data Recorder (MDR) were subjected to post-flight ground analysis. In the later years of its operational life, a data-link system could send ASARS-1 and ELINT data from about 2,000 nmi (3,700 km) of track coverage to a suitably equipped ground station.[citation needed]
A SR-71 refueling from a KC-135Q Stratotanker during a flight in 1983
The first flight of an SR-71 took place on 22 December 1964, at Air Force Plant 42 in Palmdale, California.[54] 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.[55] The United States Air Force Strategic Air Command had SR-71 Blackbirds in service from 1966 through 1991.
SR-71s first arrived at the 9th SRW's Operating Location (OL-8) at Kadena Air Base, Okinawa on 8 March 1968.[56] 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.[56] 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, England. The aircraft was flown to the National Museum of the United States Air Force near Dayton, Ohio in March 1990.
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.
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.[5]
Swedish JA 37 Viggen 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 Viggen.[57] 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.[58][59][60]
Operational highlights for the entire Blackbird family (YF-12, A-12, and SR-71) as of about 1990 included:[61]
- 3,551 Mission Sorties Flown
- 17,300 Total Sorties Flown
- 11,008 Mission Flight Hours
- 53,490 Total Flight Hours
- 2,752 hours Mach 3 Time (Missions)
- 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.
The highly specialized tooling used to manufacture the SR-71 was ordered destroyed in 1968 by then-Secretary of Defense Robert McNamara, per contractual obligations at the end of production.[citation needed] Destroying the tooling killed any chance of there being an F-12B and also limited the SR-71 force to the 32 completed, the final SR-71 order having to be cancelled when the tooling was destroyed.
In the 1970s, the SR-71 was placed under closer congressional scrutiny and, with budget concerns, the program was soon under attack. Both Congress and the USAF sought to focus on newer projects like the B-1 Lancer and upgrades to the B-52 Stratofortress, whose replacement was being developed. While the development and construction of reconnaissance satellites was costly, their upkeep was less than that of the nine SR-71s then in service.[citation needed]
The SR-71 had never gathered significant supporters within the Air Force, making it an easy target for cost-conscious politicians. Also, parts were no longer being manufactured for the aircraft, so other airframes had to be cannibalized to keep the fleet airworthy. The aircraft's lack of a datalink (unlike the Lockheed U-2) meant that imagery and radar data could not be used in real time, but had to wait until the aircraft returned to base. The Air Force saw the SR-71 as a bargaining chip which could be sacrificed to ensure the survival of other priorities. 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 usage) was used by detractors to discredit the aircraft, with the assurance given that a replacement was under development. In 1988, Congress was convinced to allocate $160,000 to keep six SR-71s (along with a trainer model) in flyable storage that would allow the fleet to become airborne within 60 days. The USAF refused to spend the money. While the SR-71 survived attempts to be retired in 1988, partly due to the unmatched ability to provide high quality coverage of the Kola Peninsula for the US Navy,[62] the decision to retire the SR-71 from active duty came in 1989, with the SR-71 flying its last missions in October that year.[63]
Funds were redirected to the financially troubled B-1 Lancer and B-2 Spirit programs. 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.[64] However, it was noted by SR-71 supporters that the SR-71B trainer was just coming out of overhaul and that one SR-71 could have been made available in a few weeks, and a second one within two months. Since the aircraft was recently retired, the support infrastructure was in place and qualified crews available. The decision was made by Washington not to bring the aircraft back.
Due to increasing unease about political conditions in the Middle East and North Korea, the U.S. Congress re-examined the SR-71 beginning in 1993.[64] At a hearing of the Senate Committee on Armed Services, Senator J. James Exon asked Admiral Richard C. Macke:
| “ |
If we have the satellite intelligence that you collectively would like us to have, would that type of system eliminate the need for an SR-71… Or even if we had this blanket up there that you would like in satellites, do we still need an SR-71? |
” |
Macke replied,
| “ |
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 [data] 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."[65] |
” |
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 timeliness 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 that "the Advanced Airborne Reconnaissance System, which was going to be an unmanned UAV" would meet the requirements but was not affordable at the time. He said that they were "looking at alternative means of doing [the job of the SR-71]."[65]
Macke told the committee that they were "flying U-2s, RC-135s, [and] other strategic and tactical assets" to collect information in some areas.[65]
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.[61]
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."[61]
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.[61] The Skunk Works was able to return the aircraft to service under budget, coming in at $72 million.[66]
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.[61]
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.[61] 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 used the line-item veto to cancel the $39 million allocated for the SR-71. In June 1998, the Supreme Court of the United States 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 plane was permanently retired in 1998. The Air Force quickly disposed of their SR-71s, leaving NASA with the two last flyable Blackbirds until 1999.[67] 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.[66]
Important dates pulled from many sources.[68][unreliable source?]
- 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 (#61-7950) delivered to Palmdale.
- 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 AF Plant #42.
- 21 July 1967: Jim Watkins and Dave Dempster fly first international sortie in SR-71A #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 were questionable.
- 5 February 1968: Lockheed ordered to destroy A-12, YF-12, and SR-71 tooling.
- 8 March 1968: First SR-71A (#61-7978) arrives at Kadena AB to replace A-12s.
- 21 March 1968: First SR-71 (#61-7976) operational mission flown from Kadena AB over Vietnam.
- 29 May 1968: CMSgt Bill Gornik begins the tie-cutting tradition of Habu crews neck-ties.
- 3 December 1975: First flight of SR-71A #61-7959 in "Big Tail" configuration.
- 20 April 1976: TDY operations started at RAF Mildenhall in SR-71A #17972.
- 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 #61-7956 flies its 1,000th sortie.
- 21 April 1989: #974 was lost due to an engine explosion after taking off from Kadena AB. This was the last Blackbird to be lost, and was the first SR-71 accident in 17 years.[3][4]
- 22 November 1989: Air Force SR-71 program officially terminated.
- 21 January 1990: Last SR-71 (#61-7962) left Kadena AB.
- 26 January 1990: SR-71 is decommissioned at Beale AFB, CA.
- 6 March 1990: Last SR-71 flight under SENIOR CROWN program, setting four speed records enroute to Smithsonian Institution.
- 25 July 1991: SR-71B #61-7956/NASA #831 officially delivered to NASA Dryden.
- October 1991: Marta Bohn-Meyer becomes first female SR-71 crew member.
- 28 September 1994: Congress votes to allocate $100 million for reactivation of three SR-71s.
- 26 April 1995: First reactivated SR-71A (#61-7971) makes its first flight after restoration by Lockheed.
- 28 June 1995: First reactivated SR-71 returns to Air Force as Detachment 2.
- 28 August 1995: Second reactivated SR-71A (#61-7967) makes first flight after restoration.
- 2 August 1997: A NASA SR-71 made multiple flybys at the EAA AirVenture Oshkosh air show. It was then supposed to perform a sonic boom at 53,000 feet (16,000 m) after a midair refueling, but a fuel flow problem caused it to divert to Milwaukee. Two weeks later, the pilot's flight path brought him over Oshkosh again, and there was, in fact, a sonic boom.
- 19 October 1997: The last flight of SR-71B #61-7956 at Edwards AFB Open House.
- 9 October 1999: The last flight of the SR-71 (#61-7980/NASA 844).
- September 2002: Final resting places of #956, #971, and #980 are made known.[69]
- 15 December 2003: SR-71 #972 goes on display at the Steven F. Udvar-Hazy Center in Chantilly, Virginia.
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 for its class: an "absolute altitude record" of 85,069 feet (25,929 m).[8][70][71][72] Several aircraft exceeded this altitude in zoom climbs but not in sustained flight.[8] 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).[8][72]
The SR-71 also holds the "Speed Over a Recognized Course" record for flying from New York to London distance 3,508 miles (5,646 km), 1,435.587 miles per hour (2,310.353 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).[73] This equates to an average velocity of about Mach 2.68, including deceleration for in-flight refueling. Peak speeds during this flight were probably 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".[74]
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 "Ed" E. Yielding and Lt. Col. Joseph "Jt" T. 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.[73]
- 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.[75] 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[76]
|
Much speculation exists regarding a replacement for the SR-71, most notably aircraft identified as the Aurora. This is due to limitations of spy satellites, which are governed by the laws of orbital mechanics. It may take up to 24 hours before a satellite is in proper orbit to photograph a particular target, far longer than a reconnaissance plane. Spy planes can provide the most current intelligence information and collect it when lighting conditions are optimum. The fly-over orbit of spy satellites may also be predicted and can allow the enemy to hide assets when they know the satellite is above, a drawback spy planes do not exhibit. These factors have led many to doubt that the US has abandoned the concept of spy planes to complement reconnaissance satellites.[77] Unmanned aerial vehicles (UAVs) are also used for much aerial reconnaissance in the 2000s. They have the advantage of being able to overfly hostile territory without putting human pilots at risk.
- SR-71A was the main production variant.
- SR-71B was a trainer variant.[78]
- SR-71C was a hybrid aircraft composed of the rear fuselage of the first YF-12A (S/N 60-6934) and the forward fuselage from a SR-71 static test unit. The YF-12 had been wrecked in a 1966 landing accident. This Blackbird was seemingly not quite straight and had a yaw at supersonic speeds.[79] It was nicknamed "The Bastard".[80][81]
Data from SR-71.org,[82] Pace[83]
General characteristics
- Crew: 2
- Payload: 3,500 lb (1,600 kg) of sensors
- Length: 107 ft 5 in (32.74 m)
- Wingspan: 55 ft 7 in (16.94 m)
- Height: 18 ft 6 in (5.64 m)
- Wing area: 1,800 ft2 (170 m2)
- Empty weight: 67,500 lb (30,600 kg)
- Loaded weight: 152,000 lb (69,000 kg)
- Max. takeoff weight: 172,000 lb (78,000 kg)
- Powerplant: 2 × Pratt & Whitney J58-1 continuous-bleed afterburning turbojets, 34,000 lbf (151 kN) each
- Wheel track: 16 ft 8 in (5.08 m)
- Wheelbase: 37 ft 10 in (11.53 m)
- Aspect ratio: 1.7
Performance
- Maximum speed: Mach 3.3[83][84][N 4] (2,200+ mph, 3,530+ km/h, 1,900+ knots) at 80,000 ft (24,000 m)
- Range: 2,900 nmi (5,400 km)
- Ferry range: 3,200 nmi (5,925 km)
- Service ceiling: 85,000 ft (25,900 m)
- Rate of climb: 11,810 ft/min (60 m/s)
- Wing loading: 84 lb/ft² (410 kg/m²)
- Thrust/weight: 0.44
SR-71 at Pima Air & Space Museum, Tucson, Arizona
Close-up of the SR-71B operated by NASA’s Dryden Flight Research Center, Edwards, California
Twelve SR-71s were lost and one pilot died in accidents during the aircraft's service career.[3][4] Eleven of these accidents happened between 1966 and 1972.
List of SR-71 Blackbirds
| Serial number |
Model |
Location or fate |
| 61-7950 |
SR-71A |
Lost, 10 January 1967 |
| 61-7951 |
SR-71A |
Pima Air & Space Museum, Tucson, Arizona |
| 61-7952 |
SR-71A |
Lost, 25 January 1966[86] |
| 61-7953 |
SR-71A |
Lost, 18 December 1969[87] |
| 61-7954 |
SR-71A |
Lost, 11 April 1969 |
| 61-7955 |
SR-71A |
Air Force Flight Test Center Museum, Edwards Air Force Base, California[88] |
| 61-7956 |
SR-71B |
Air Zoo, Kalamazoo, Michigan |
| 61-7957 |
SR-71B |
Lost, 11 January 1968 |
| 61-7958 |
SR-71A |
Museum of Aviation, Warner Robins, Georgia |
| 61-7959 |
SR-71A |
Air Force Armament Museum, Eglin Air Force Base, Florida[89] |
| 61-7960 |
SR-71A |
Castle Air Museum, Atwater, California |
| 61-7961 |
SR-71A |
Kansas Cosmosphere and Space Center, Hutchinson, Kansas |
| 61-7962 |
SR-71A |
American Air Museum in Britain, Imperial War Museum Duxford, Cambridgeshire, England[90] |
| 61-7963 |
SR-71A |
Beale Air Force Base, Marysville, California |
| 61-7964 |
SR-71A |
Strategic Air and Space Museum, Ashland, Nebraska |
| 61-7965 |
SR-71A |
Lost, 25 October 1967 |
| 61-7966 |
SR-71A |
Lost, 13 April 1967 |
| 61-7967 |
SR-71A |
Barksdale Air Force Base, Bossier City, Louisiana |
| 61-7968 |
SR-71A |
Virginia Aviation Museum, Richmond, Virginia |
| 61-7969 |
SR-71A |
Lost, 10 May 1970 |
| 61-7970 |
SR-71A |
Lost, 17 June 1970 |
| 61-7971 |
SR-71A |
Evergreen Aviation Museum, McMinnville, Oregon |
| 61-7972 |
SR-71A |
Steven F. Udvar-Hazy Center, Washington Dulles International Airport, Chantilly, Virginia |
| 61-7973 |
SR-71A |
Blackbird Airpark, Palmdale, California |
| 61-7974 |
SR-71A |
Lost, 21 April 1989 |
| 61-7975 |
SR-71A |
March Field Air Museum, Riverside, California[91] |
| 61-7976 |
SR-71A |
National Museum of the United States Air Force, Wright-Patterson Air Force Base, near Dayton, Ohio |
| 61-7977 |
SR-71A |
Lost, 10 October 1968 |
| 61-7978 |
SR-71A |
Lost, 20 July 1972[3] |
| 61-7979 |
SR-71A |
Lackland Air Force Base, San Antonio, Texas |
| 61-7980 |
SR-71A |
Dryden Flight Research Center, Edwards Air Force Base, California |
| 61-7981 |
SR-71C |
Hill Aerospace Museum, Hill Air Force Base, Ogden, Utah (formerly YF-12A 60-6934) |
Notes: Many secondary references use apparently incorrect 64- series aircraft serial numbers (e.g. SR-71C 64-17981), but no primary government documents have been found to support this.[92]
After completion of all USAF and NASA SR-71 operations at Edwards, the SR-71 Flight Simulator was moved in July 2006 to the Frontiers of Flight Museum at Love Field Airport in Dallas, Texas.[93]
- Related development
- Aircraft of comparable role, configuration and era
- Related lists
- Notes
- ^ See the opening fly page in Paul Crickmore's book SR-71, Secret Missions Exposed, which contains a copy of the original R-12 labeled plan view drawing of the vehicle.
- ^ Crickmore SR-71, Secret Missions Exposed, original R-12 labeled plan view drawing
- ^ See Blackbird with Canards image for visual.
- ^ Maximum speed limit was Mach 3.2, but could be raised to Mach 3.3 if the engine compressor inlet temperature did not exceed 801 °F (427 °C).[85]
- Citations
- ^ "SR-71 Blackbird." lockheedmartin.com. Retrieved: 14 March 2010.
- ^ a b "SR71 Blackbird." PBS documentary, Aired: 15 November 2006.
- ^ a b c d Landis and Jenkins 2005, pp. 98, 100–101.
- ^ a b c Pace 2004, pp. 126–127.
- ^ a b Crickmore 1997, p. 64.
- ^ Landis and Jenkins 2005, p. 78.
- ^ Pace 2004, pp. 159.
- ^ a b c d "Records: Sub-class : C-1 (Landplanes) Group 3: turbo-jet." records.fai.org. Retrieved: 30 June 2011.
- ^ Rich and Janos 1994, p. 85.
- ^ McIninch 1996, p. 31.
- ^ a b c Robarge, David. "A Futile Fight for Survival. Archangel: CIA's Supersonic A-12 Reconnaissance Aircraft." CSI Publications, 27 June 2007. Retrieved: 13 April 2009.
- ^ a b Landis and Jenkins 2005, pp. 56–57.
- ^ McIninch 1996, p. 29.
- ^ McIninch 1996, pp. 14–15.
- ^ Merlin 2005, pp. 4–5.
- ^ Merlin 2005, p. 6.
- ^ Crickmore 2009, pp. 30–31.
- ^ Lockheed obtained the metal from the USSR at the height of the Cold War, using many guises to prevent the Soviet government from knowing what it was to be used for.
- ^ "SR-71 manual, Air Inlet System." sr-71.org. Retrieved: 14 March 2010.
- ^ "Penn State- turbo ramjet engines." personal.psu.edu. Retrieved: 14 March 2010.
- ^ a b c d e f Johnson 1985
- ^ a b c Shul and O'Grady 1994
- ^ Crickmore 1997, pp. 42–43.
- ^ Landis and Jenkins 2005, p. 97.
- ^ Rich and Janos 1994, p. 221.
- ^ Landis and Jenkins 2005, p. 83.
- ^ Rich and Janos 1994, pp. 213–214.
- ^ Rich and Janos 1994, p. 203.
- ^ McIninch 1996, p. 5.
- ^ Graham, 1996, p. 75
- ^ Rich and Janos 1994, p. 36.
- ^ Hott, Bartholomew and George E. Pollock. "The Advent, Evolution, and New Horizons of United States Stealth Aircraft." ics.purdue.edu. Retrieved: 5 May 2007.
- ^ "MiG-25 Foxbat". globalaircraft.org. http://www.globalaircraft.org/planes/mig-25_foxbat.pl. Retrieved 31 May 2011.
- ^ Suhler 2009, p. 100.
- ^ Suhler 2009, ch. 10.
- ^ AirPower May 2002, p. 36.
- ^ SR-71 Gallery
- ^ Goodall 2003, p. 19.
- ^ AirPower, May 2002, p. 33.
- ^ Donald 2003, p. 172.
- ^ Popular Mechanics, June 1991, p. 28.
- ^ Kloesel, Kurt J.; Ratnayake, Nalin A.; Clark, Casie M.. "A Technology Pathway for Airbreathing, Combined-Cycle, Horizontal Space Launch Through SR-71 Based Trajectory Modeling". NASA. Dryden Flight Research Center. http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110013567_2011014030.pdf. Retrieved 7 September 2011.
- ^ "SR-71." yarchive.net. Retrieved: 14 March 2010.
- ^ Kloesel, Kurt J., Nalin A. Ratnayake and Casie M. Clark. "A Technology Pathway for Airbreathing, Combined-Cycle, Horizontal Space Launch Through SR-71 Based Trajectory Modeling." NASA Dryden Flight Research Center. Retrieved: 7 September 2011.
- ^ "Blackbird manual." sr-71.org. Retrieved: 14 March 2010.
- ^ "Aerostories." aerostories.free.fr. Retrieved: 14 March 2010.
- ^ Colville, Jesse R. "Axisymmetric Inlet Design for Combined Cycle Engines." Digital Repository at the University of Maryland, 1993.
- ^ Landis and Jenkins 2005, pp. 95–96.
- ^ SR-71A-1 Flight Manual, Section IV p. 3. Retrieved 13 Dec. 2011.
- ^ The original B-1A Offensive Avionics Request For Proposal (RFP) required the installation and integration of an NAS-14 system, but cost-cutting changes later deleted it from the B-1. Some U-2Rs did receive the NAS-21 system, but newer inertial and GPS systems replaced them.
- ^ a b c d Crickmore 1997, p. 74.
- ^ Crickmore 1997, p. 563.
- ^ Crickmore 1997, p. 77.
- ^ Crickmore 1997, pp. 56, 58.
- ^ Crickmore 1997, p. 59.
- ^ a b Crickmore 1997, pp. 62–64.
- ^ Flyghistorisk Revy – System 37 Viggen, Stockholm: Svensk Flyghistorisk Förening, 2009, ISSN 0345-3413
- ^ Mach 14, vol 4, no 3, 1983, p. 5. ISSN 0280-8498.
- ^ Mach 25, vol 7, no 2, 1986, pp. 28–29. ISSN 0280-8498.
- ^ Darwal 2004, pp. 151–156.
- ^ a b c d e f Graham 1996
- ^ Crickmore 1997, pp. 84–85.
- ^ Crickmore 1997, p. 81.
- ^ a b Remak and Ventolo 2001
- ^ a b c "Department of Defense Authorization for Appropriations for Fiscal Year 1994 and The Future Years." United States Senate, May–June 1993.
- ^ a b Jenkins 2001
- ^ "NASA/DFRC SR-71 Blackbird." NASA. Retrieved: 16 August 2007.
- ^ "SR-71." sr-71.org. Retrieved: 14 March 2010.
- ^ SR-71.org (2002), SR-71 Online Headlines Archive, http://www.sr-71.org/news/headlines.php, retrieved 2011-12-06, "On Saturday, 14 September 2002, SR-71A #980 was put on display at the entrance of Dryden Flight Research Center. The concrete hardstand has not yet been built.
It is also apparent that SR-71B #956 will be going to the Air Zoo in Kalamazoo, MI and SR-71A #971 will be going to the Evergreen Aviation Museum in McMinnville, OR.
With these announcements, all SR-71s have been allocated to museums."
- ^ Landis and Jenkins 2005, pp. 77–78.
- ^ Altitude record
- ^ a b A-12, YF-12A, & SR-71 Timeline of Events
- ^ a b "Blackbird Records." sr-71.org. Retrieved: 18 October 2009.
- ^ "1966 Lockheed SR-71". http://www.vam.smv.org/pdfs/VAMHistoricAircraft.pdf. Retrieved 14 Feb 2011.
- ^ National Aeronautic Association
- ^ SR-71 Revealed: The Inside Story
- ^ Siuru, William D. and John D. Busick. Future Flight: The Next Generation of Aircraft Technology. Blue Ridge Summit, Pennsylvania: TAB Books, 1994. ISBN 0-8306-7415-2.
- ^ Landis and Jenkins 2005, pp. 56–58.
- ^ Landis and Jenkins 2005, pp. 62, 75.
- ^ Merlin 2005, p. 4.
- ^ Pace 2004, pp. 109–110.
- ^ "Lockheed SR-71 Blackbird page." sr-71.org. Retrieved: 14 March 2010.
- ^ a b Pace 2004, p. 110.
- ^ Graham 1996, p. 48.
- ^ Graham 2002, pp. 93, 223.
- ^ "BILL WEAVER SR-71 Breakup". Roadrunners Internationale. 10 September 2011. http://roadrunnersinternationale.com/weaver_sr71_bailout.html. Retrieved 3 March 2012.
- ^ SR-71 #953 crash. check-six.com
- ^ SR-71A Blackbird Air Force Flight Center Museum. Retrieved: 10 February 2009.
- ^ Exhibits. Air Force Armament Museum. Retrieved: 10 February 2009.
- ^ "Aircraft On Display: Lockheed SR-71A Blackbird." The American Air Museum, Imperial War Museum. Retrieved: 10 February 2009.
- ^ "Aircraft: Lockheed SR-71A Blackbird." March Field Air Museum. Retrieved: 10 February 2009.
- ^ U-2 / A-12 / YF-12A / SR-71 Blackbird & RB-57D – WB-57F locations.' u2sr71patches.co.uk. Retrieved: 22 January 2010.
- ^ "Frontiers of Flight Museum." flightmuseum.com. Retrieved: 14 March 2010.
- Bibliography
- "A Bittersweet and Fancy Flight." Philadelphia Inquirer, 7 March 1990, p. 1.
- Crickmore, Paul F. "Blackbirds in the Cold War". Air International, January 2009, pp. 30–38. Stamford, UK: Key Publishing.
- Crickmore, Paul F. "Lockheed's Blackbirds – A-12, YF-12 and SR-71A". Wings of Fame, Volume 8, 1997, pp. 30–93. London: Aerospace Publishing. ISBN 1-86184-008-X.
- Donald, David, ed. "Lockheed's Blackbirds: A-12, YF-12 and SR-71". Black Jets. AIRtime, 2003. ISBN 1-880588-67-6.
- Goodall, James. Lockheed's SR-71 "Blackbird" Family. Hinckley, UK: Aerofax/Midland Publishing, 2003. ISBN 1-85780-138-5.
- Graham, Richard H. SR-71 Blackbird: Stories, Tales, and Legends. North Branch, Minnesota: Zenith Imprint, 2002. ISBN 0-7603-1142-0.
- Graham, Richard H. SR-71 Revealed: The Inside Story. St. Paul, Minnesota: MBI Publishing Company, 1996. ISBN 978-0-7603-0122-7.
- Jenkins, Dennis R. Lockheed Secret Projects: Inside the Skunk Works. St. Paul, Minnesota: MBI Publishing Company, 2001. ISBN 978-0-7603-0914-8.
- Johnson, C.L. Kelly: More Than My Share of it All. Washington, DC: Smithsonian Books, 1985. ISBN 0-87474-491-1.
- Landis, Tony R. and Dennis R. Jenkins. Lockheed Blackbirds. Minneapolis, Minnesota: Specialty Press, revised edition, 2005. ISBN 1-58007-086-8.
- McIninch, Thomas. "The Oxcart Story". Center for the Study of Intelligence, Central Intelligence Agency, 2 July 1996. Retrieved: 10 April 2009.
- Merlin, Peter W. From Archangel to Senior Crown: Design and Development of the Blackbird., Reston, Virginia: American Institute of Aeronautics and Astronautics (AIAA), 2008. ISBN 978-1-56347-933-5.
- Merlin, Peter W. "The Truth is Out There... SR-71 Serials and Designations". Air Enthusiast, No. 118, July/August 2005. Stamford, UK: Key Publishing, pp. 2–6. ISSN 0143-5450.
- Pace, Steve. Lockheed SR-71 Blackbird. Swindon, UK: Crowood Press, 2004. ISBN 1-86126-697-9.
- Remak, Jeannette and Joe Ventolo, Jr. A-12 Blackbird Declassified. St. Paul, Minnesota: MBI Publishing Company, 2001. ISBN 0-7603-1000-9.
- Rich, Ben R. and Leo Janos. Skunk Works: A Personal Memoir of My Years at Lockheed. New York: Little, Brown and Company, 1994. ISBN 0-316-74330-5.
- Shul, Brian and Sheila Kathleen O'Grady. Sled Driver: Flying the World's Fastest Jet. Marysville, California: Gallery One, 1994. ISBN 0-929823-08-7.
- Suhler, Paul A. From RAINBOW to GUSTO: Stealth and the Design of the Lockheed Blackbird (Library of Flight Series) . Reston, Virginia: American Institute of Aeronautics and Astronautics (AIAA), 2009. ISBN 978-1-60086-712-5.
- Additional sources
- Brandt, Steven A., Randall J. Stiles and John J. Bertin. Introduction to Aeronautics: A Design Perspective. Reston, VA: American Institute of Aeronautics & Astronautics, 2004, pp. 141–150. ISBN 1-56347-701-7.
- Brown, Kevin V. "America's SuperSecret Spy Plane." Popular Mechanics, June 1968, pp. 59–62, 190.
- Clarkson, Jeremy. I Know You Got Soul. Penguin Books Limited, 2006. ISBN 0-14-102292-2.
- Crickmore, Paul F. Lockheed Blackbird: Beyond the Secret Missions. London: Osprey Publishing, 2004. ISBN 1-84176-694-1.
- Crickmore, Paul and Jim Laurier. Lockheed SR-71 Operations in the Far East. Oxford, UK: Osprey Publishing, 2008. ISBN 1-84603-319-5.
- Darwall, Bjarne. Luftens Dirigenter(Air Conductors) (in Swedish). Nässjö, Sweden: Air Historic Research AB, 2004. ISBN 91-973892-6-9.
- Goodall, James and Jay Miller. "Lockheed's SR-71 'Blackbird' Family A-12, F-12, M-21, D-21, SR-71". Hinckley, UK: AeroFax-Midland Publishing, 2002. ISBN 1-85780-138-5.
- Graham, Richard H. SR-71 Revealed: The Inside Story. Osceola, WI: Motorbooks International, 1996. ISBN 0-7603-0122-0.
- Grant, R.G. Flight: 100 Years of Aviation. New York: DK Publishing, 2007. ISBN 978-0-7566-1902-2.
- Hobson, Chris. Vietnam Air Losses, USAF, USN, USMC, Fixed-Wing Aircraft Losses in Southeast Asia 1961–1973. North Branch, Minnesota: Specialty Press, 2001. ISBN 1-85780-115-6.
- Merlin, Peter. Mach 3+: NASA USAF YF-12 Flight Research 1969–1979. Washington, D.C.: Diane Publishing Co., NASA History Division Office, 2002. ISBN 1-4289-9458-0.
- Pappas, Terry. "The Blackbird is Back." Popular Mechanics, June 1991, pp. 27–31, 104–105.
- Periscope Film Com. Sr-71 Blackbird Pilot's Flight Manual. Lulu.com, 2006. ISBN 1-4116-9937-8.
- Reithmaier, Lawrence W. Mach 1 and Beyond. New York: McGraw-Hill, 1994, pp. 220–237. ISBN 0-07-052021-6.
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Manufacturer
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Basic Model
Numbers
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Lockheed-California
Temporary Design
Numbers
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Airliners and
civil transports
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Military transports
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Attack and bombers
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Drones/UAVs
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EW and
reconnaissance
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Fighters
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Helicopters
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Maritime patrol
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Trainers
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Experimental
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| Bomber |
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| Light bomber |
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| Heavy bomber |
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| Long-range bomber |
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- See also: B-20 (redesignation of A-20 in 1948)
- B-26 (redesignation of A-26 in 1948)
- SR-71 (designation in bomber sequence)
- Post-1962 list
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![An air-to-air overhead front view of an SR-71A strategic reconnaissance aircraft. Note the water vapor, condensed by the low-pressure vortices generated by the chines outboard of each engine inlet. SR-71 development began using a coal slurry power plant,[15] but Johnson determined that the coal particles damaged engine components. He then began researching a liquid hydrogen power plant, but the tanks required to store cryogenic hydrogen did not suit the Blackbird's form factor.](http://web.archive.org./web/20120829150815/http://cdn5.wn.com/pd/d1/44/85a53b9c47738d60c2db17741e0e_medium.jpg "An air-to-air overhead front view of an SR-71A strategic reconnaissance aircraft. Note the water vapor, condensed by the low-pressure vortices generated by the chines outboard of each engine inlet. SR-71 development began using a coal slurry power plant,[15] but Johnson determined that the coal particles damaged engine components. He then began researching a liquid hydrogen power plant, but the tanks required to store cryogenic hydrogen did not suit the Blackbird's form factor.")
![F4U Corsair The center makes its first media appearance in the 2009 film Transformers: Revenge of the Fallen. The center remained open while filming took place, although certain areas were closed.[7] The SR-71 that is on display in the museum will be used as the Autobot Jetfire in the film.](http://web.archive.org./web/20120829150815/http://cdn9.wn.com/pd/ee/97/67abbfc7f14454691a82b4c3e767_medium.jpg "F4U Corsair The center makes its first media appearance in the 2009 film Transformers: Revenge of the Fallen. The center remained open while filming took place, although certain areas were closed.[7] The SR-71 that is on display in the museum will be used as the Autobot Jetfire in the film.")
