Exactly fifty years ago, in November 1969, a somewhat anecdotal incident occurred: the latest American unmanned aerial vehicle Lockheed D-21B landed near Baikonur. Outwardly, the new reconnaissance aircraft looked like a smaller version of the famous strategic supersonic reconnaissance aircraft Lockheed SR-71 Blackbird ("Blackbird"), the predecessor of which was its carrier aircraft. Acquaintance with the novelty of the American military-industrial complex led to the beginning of work on the creation of a similar aircraft. At the Tupolev Design Bureau, work began on the Soviet response - the Raven reconnaissance drone, which in the future was supposed to be carried by the Tu-160 strategic supersonic bomber.
How Lockheed D-21B ended up near Baikonur
The novelty of the American military-industrial complex fell into the hands of the Soviet military and engineers after its very first flight, and in total 17 launches were carried out according to the program, of which only 4 full-fledged combat missions, all of them took place over the territory of China. It is worth noting that the Americans came to the idea of using strategic reconnaissance drones under the pressure of circumstances. The starting point was the shooting down in the sky over the Sverdlovsk region on May 1, 1960, of an American U-2 reconnaissance aircraft with pilot Francis Gary Powers on board. This incident led to the CIA banning manned reconnaissance flights over the territory of the Soviet Union. At the same time, the need for obtaining intelligence information has not gone anywhere, and the main American intelligence agency has initiated work on the creation of special drones.
The first flight of the new reconnaissance unmanned aerial vehicle, designated Lockheed D-21, took place on December 22, 1964. The drone, which received a ramjet rocket engine, had remarkable flight characteristics. The device could accelerate to a speed of more than Mach 3.6 at an altitude of about 30 kilometers, and the range of the reconnaissance drone was more than two thousand kilometers. To launch the first drones, a version of the Lockheed A-12 reconnaissance aircraft - M21, specially adapted for these purposes, was used. In the future, it is the modified version of this aircraft, which has become longer and heavier than its predecessor, the Lockheed A-12, that will become the much more famous Blackbird.
The symbiosis of the Lockheed A-12 (M21) reconnaissance aircraft and the D-21A drone was interrupted by a disaster during the next launch, which took place in July 1966. After this disaster, a new version of the Lockheed D-21B drone was developed, adapted for launch from the B-52H bomber. At the same time, a strategic bomber could carry two reconnaissance drones at once. Despite the fact that the test flights were accompanied by various incidents, including the failure of the autopilot, the reconnaissance drones, along with the B-52H carrier aircraft, entered service with the special 4200 test squadron, whose specialization was reconnaissance flights over Chinese territory.
Like American reconnaissance aircraft, the new drone flew at great altitude and supersonic speed, solving the same espionage missions. But, unlike airplanes, after completing the mission, the Lockheed D-21 drone did not land, but dropped the container with the film filmed in flight, after which it self-destructed. The new reconnaissance drone was originally designed to be disposable, which, according to the developers, should have minimized its weight and cost. The design of the UAV itself was mainly made of titanium using high-strength steels, and a number of elements were made from emerging radio-absorbing composite materials. The salient features of the reconnaissance drone were its smaller size compared to aircraft and its clean aerodynamic shape. Like its older friend Lockheed SR-71 Blackbird, the new drone was covered with a special black ferrite paint, which helped to dissipate heat from the surface of the hull, and also reduce the radar signature of the aircraft.
The Lockheed D-21B reconnaissance drone made its first truly combat flight in November 1969. The very first flight turned into a real embarrassment. After the drone completed the removal of Chinese nuclear facilities located in the area of Lake Lob-Nor (there was a nuclear test site), the device continued its flight towards the USSR, although on instructions it was supposed to go on the opposite course. The reconnaissance flight continued until the fuel was completely depleted and ended a few hundred kilometers from the Tyura-Tam (Baikonur) test site in Kazakhstan. The Americans assumed that their reconnaissance vehicle did not arrive at the designated area to drop the container with the film taken off due to a malfunction in the software of the vehicle and its navigation system, and, most likely, they were right.
Soviet response in the face of the Raven drone
The Soviet military and engineers were impressed by the new American intelligence apparatus, which fell into their hands by a lucky coincidence. The created commission highly appreciated the flight capabilities of the drone, which became the basis for initiating work on the creation of a similar device of Soviet production. The developer of the Soviet unmanned reconnaissance aircraft was the Tupolev Design Bureau, the Raven UAVs being developed by its designers were supposed to be launched from the side of modified Tu-95 strategic bombers, and in the future from the supersonic Tu-160. The main goal of the designers at the first stage of work was to create an aircraft similar to the captured one, but using domestic structural materials, avionics and engines.
The Soviet designers were interested in the high performance characteristics of the American drone in their hands. In many ways, these were preliminary estimates, according to which the maximum flight altitude was about 25 kilometers, the speed was up to 3600 km / h. The aerodynamic design of the Lockheed D-21B was also of interest, the drone was made according to the tailless design with a thin delta wing of a large sweep. The designers appreciated both the high aerodynamic qualities and the layout perfection of the model.
Like the overseas model, the Soviet "Raven" was designed as a specialized reconnaissance vehicle capable of high-altitude flights over long distances. The Raven was supposed to collect reconnaissance data after launching from a carrier aircraft; at the initial design stage, the possibility of launching a drone from the ground was also provided, but later this idea was recognized as inexpedient and unpromising due to the large size and small maneuverability of the launch complex. After the completion of the reconnaissance mission, the Soviet drone was supposed to drop a container with the footage over the territory of countries friendly to the Soviet Union. It was planned to install a powerful supersonic ramjet engine (SPVRD) RD-012 on the drone. Its power was enough for the device to reach a maximum speed of Mach 3, 3 … 3, 6 when flying at an altitude of 23-27 kilometers. At the same time, to bring the unmanned reconnaissance vehicle to the design operating mode of the SPRVD, it was planned to use a suspended powder accelerator after launch from the carrier.
According to the project being developed, the drone was to be included, together with the carrier aircraft, in the operational and strategic aerial reconnaissance complex. In the future, the "Raven" was to be used in conjunction with other ground and air support means. The development of the Crow continued for several years. Despite the fact that the drone did not leave the design status, these works were of great importance for the further development of supersonic aviation and the design of new aircraft.
The fate of two projects
The fate of the two reconnaissance vehicles was directly influenced by technological progress. The American Lockheed D-21B made only four reconnaissance flights. This technology could not compete with more and more advanced space reconnaissance means. At the same time, the American device, despite its disposability, was quite expensive to manufacture, and the very use of the drone for reconnaissance missions was considered unsuccessful, which cost only the first flight, which unexpectedly ended in the Kazakh steppes.
The Soviet project, in addition to the above circumstances, fell victim to the lack of high-quality photographic equipment. The level of intelligence equipment, according to some experts, was the main factor in the curtailment of work on the Voron in the 1970s. In those years, the country did not produce special reconnaissance equipment that would provide the apparatus with the possibility of all-weather aerial reconnaissance when operating from very high altitudes. At the same time, as noted above, the project was not useless, since the technologies and solutions developed were then used in the design of new Soviet supersonic aircraft, as well as in work on the creation of hypersonic aircraft.
