The operational wear of the Blackbirds was considerable, with some aircraft arriving with damage that required considerable repairs. Between 1968 and 1969 the SR-71 carried out an average of one sortie a week, although in 1970 the average rose to two and from 1972 it was usual for them to carry out one mission a day. During their campaign in Vietnam it is estimated that the North Vietnamese air defense fired over 800 SAM missiles at them, none of which hit their target, although 2 Blackbirds were lost due to mechanical failure.The Blackbirds were also deployed in Europe during the Cold War, more specifically at the RAF Mildenhall base in England. They made sorties following two flight paths. One of them went through the coast of Norway to the Kola Peninsula and the other from Mildenhall to the Baltic Sea, known as “Baltic Express”. One of its main missions in this period was to control the movements of the Soviet Northern Fleet. Several mechanical problems suffered during these missions were about to cause serious crises with the Soviet Union on more than one occasion.In the mid-1980s, a wave of rejection of the operational maintenance of the SR-71 arose in the Pentagon. One of the main reasons was that in reality most of the data obtained was used by intelligence agencies such as the NSA, CIA or DIA and not by the military. The annual cost of these planes was also questioned since although it was about 300 million dollars a year, figures of between 500 and 700 million were given in order to win supporters for the “anti Blackbird” cause. Much of the blame for these accusations was motivated by political and general ignorance about the type of missions carried out and the strategic importance of the information provided.Finally, it was considered that the lack of data-link that would allow the SR-71 to send data in real time, (which the U-2 could do at that time), was the key factor to keep these aircraft in service or not. The detractors not only prevented the aircraft from being provided with a data-link, but also decided to provide them with an expensive improvement in their sensors. This didn’t add much to their capabilities, but it did help critics make more accusations against keeping them in service because of the high cost, which is truly cynical! In the end, in 1990, the last Blackbirds were withdrawn from active service…..temporarily.In 1993, Congress reached agreement to reactivate 3 of the Blackbirds held in reserve. 100 million dollars were earmarked for the start-up of these aircrafts, which would be part of the 9th Reconnaissance Wing at Edwards AFB. Former active crew members who were willing to return to the Blackbirds were contacted and the installation of a new data-link was approved, allowing the transmission of data from the ASAR-1 radar in near real time to ground bases. It seemed that the future smiled again at the SR-71.Time passed, and nothing happened, worse still, the funds were cut to 72.5 million dollars and the USAF did not allocate funds for the reactivation. Although in June 1995 one SR-71 was reactivated and sent to the 9th Reconnaissance Wing at Edwards AFB, in 1996 the USAF practically abandoned the project and although Congress authorized the funds again, in October 1997 President Bill Clinton used his veto right and canceled 39 million dollars intended for the Blackbirds. In June 1998 the U.S. The Supreme Court declared this veto unconstitutional, but finally in September 1998 the USAF allocated the available funds to other activities and canceled the entire reactivation project. Only NASA continued to use two SR-71s until 1999, when they were also retired.The first promotion of pilots and RSOs for the SR-71 was formed in early 1966 and consisted of 57 members. A system similar to that required to enter the USAF’s Thunderbirds aerobatic team was followed. The applicants had to have 1,500 hours of jet flight and had to pass the demanding physical exam of the Aerospace Research Pilot School, the same one that NASA astronauts passed. Once this test was passed, their service record was assessed and the most suitable were sent to Beale AFB for a week to carry out interviews, simulator flights and flights in the T-38 Talon jet trainer. Normally, only 10% of the applicants were selected by the 9th Strategic Reconnaissance Wing.Despite being elite pilots, due to the special characteristics of their missions, these pilots did not have the recognition they deserved as astronauts or aerobatic pilots. Once certified “mission ready”, these pilots would only fly actual missions. The electronic systems and procedures were so complicated that once an optimum operational level was reached by the crew, it had to be maintained at all costs, so members of different crews were rarely exchanged.(SR-71B image). Before getting into a real Blackbird. the pilot had to complete around 100 flight hours in the simulator and the RSO around 120. Training in the simulator was so stressful, due to the number of simulated contingencies, that when the crew members made their first real flight, they found it as simple as a walk in the park. The simulator training phase ended with the so-called “final check-ride”, which was a training mission in which all its parameters were recorded to be later analyzed and assessed by a pilot and an RSO evaluator.(RSO’s cockpit image). It might seem that any mission in a jet fighter or attack aircraft would be more demanding than flying a Blackbird without constant course changes and high G maneuvers, but this is just a wrong assumption. According to all the SR-71 crew, the job of keeping track of the exact parameters marked in the missions was an exhausting task, both physically and mentally. In the assigned missions, the established parameters had to be followed 100%, without a minute to relax or “admire the magnificent views”.Flying in the SR-71 was something quite special for its pilots and required a lot of preparations before takeoff, because once in the air the whole mission depends exclusively on them. The pilots arrived at the base 3 hours before the flight. After having breakfast foods rich in protein, such as steaks and eggs, the crew members underwent a medical examination and they headed to put on specialized protective pressurized suits, task that took 30 minutes. These 100,000 dollars pressurized suits incorporated an emergency oxygen supply system in case of having to carry out an emergency ejection at Mach 3 speed.They were then taken to the aircraft in vehicle that constantly refrigerated the flight suits. Even during the wait to ascend to the cockpit, the suits were cooled by portable equipment. After the mandatory pre-flight inspection, the crew members entered their cockpits, about 50 minutes before takeoff, and their helmets were hermetically sealed. Both crew members then breathed 100% pure oxygen to remove any traces of nitrogen from their blood. Due to the long duration of some missions, the crew could ingest some drinks and light meals prepared in sealed containers that fit plastic tubes that were inserted through the lower front base of the helmet. This system was the same as that used on the U-2 aircraft.Once the ground staff had warmed up the engines, passing hot air that liquefied the oil used by them, they could be started. The oil used in the J-58 engines was almost solid at room temperature, so it needed this preparation on the ground. Finally, 40 minutes before take-off, the engines were started, with a 2-minute interval between them to check the systems. The last 15 minutes were used by the pilots to go through a long list of checks.The mission tapes that controlled Northrop’s astroinertial guidance system were loaded several hours before the flight. The aircraft takes to the runway surrounded by security and support cars, and the runway was checked so that there were no foreign objects that can penetrate the J-58 turbo-ramjets and damage them. Then the Blackbird accelerates along the 1,200 meter runway and climbs with an angle of attack of +15º. The aircraft had handle problems on subsonic speeds, which must be monitored at all times.(Pilot’s cockpit image). By having delta-type wings, the SR-71 can stall without the pilots being aware of it, in their own words “the aircraft falls from the sky.” After takeoff, the first thing they did was meet one of the several tanker aircraft on the route, since fuel consumption was one of its weak points. Both aircraft knew their meeting point by means of an uninterrupted encrypted telemetry system and an ADF automatic goniometer. The operation was carried out in radio silence to avoid possible detections. Both the climb and the cruise flight were carried out using the autopilot, which received information from the astro-inertial navigation system, in order to adjust exactly to the mission path.With full tanks, the SR-71 begins the supersonic ascent. A so-called “dipsy” maneuver is performed before reaching operational altitude. The aircraft climbed up to 2,400 meters in subsonic regime and after making a dive of 1,000 meters to get the right temperature, it accelerated until it passed Mach 1. Then it climbed to its operating height of 24,000 meters in a very precise and calculated way, controlling the engine, fuel consumption and the air intake system at all times. Every time the Blackbird refueled, it had to carry out this operation and after the last refueling, it entered the “sensitive area”, that is, where it carried out the reconnaissance.The SR-71 did not fly over the target, but instead “looked” at the hostile territory from international airspace. Thanks to its altitude, it covered immense surface areas and used its speed to do this in a short time, thereby achieving a high degree of surprise. The sensors and cameras were mainly used for detection of military installations and large armoured formations. In addition, it carried out electronic signal gathering missions (SIGINT) that in the later years were sent to ground stations through a secure digital data link. Normally, the crewmen only had to observe that the flight conformed to the pre-established parameters and did not operate the scanning radars or the electronic surveillance equipment manually.The SR-71 could not roll more than 35º, so its complete turns had a radius of up to 350 km when it was made at maximum speed. When the mission ended, the aircraft used to have to carry out some more refueling, which put the pilot’s skill to the test, since the smallest error in the starting point of the descent, translated into losing the aircaft tanker by a long distance, with the consequent danger. After refueling, the aircraft usually made several circuits at low altitude to cool the airframe before landing. The descent stage was carried out following a strict guideline of established speeds and heights and with the autopilot activated.Finally, the pre-landing process was carried out in a similar way to that of any combat jet, making the SR-71 a very soft landing aircraft thanks to the arrangement of its wings. As soon as the aircraft landed, it was stored in a hangar where a very long and complicated post-flight process began. All data was extracted from the sensors for analysis and all the oil was drained from the engines to prevent it from solidifying. After getting off the aircraft, the pilots reported on the mission and underwent a medical examination, then the mission was concluded, and usually it was time to take a well-deserved break.
