Yak-28: the legendary aircraft of the Irkutsk aircraft plant

2024 Author: Matthew Elmers | [email protected]. Last modified: 2023-12-16 21:49

Yak-28 is a multifunctional supersonic jet aircraft. The most widely used versions of the supersonic front-line bomber and fighter-interceptor.

The Yak-28 became the first large-scale supersonic front-line bomber in the USSR. The aircraft was serially produced from 1960 to 1972. A total of 1180 aircraft of various modifications were produced, of which 697 were assembled in Irkutsk at a local aircraft building plant (according to the newspaper "Irkutsk Aviastroitel").

Today, it is the Yak-28 aircraft that stands on the pedestal in front of the checkpoints of the Irkutsk aircraft plant. The opening of the monument on which the Yak-28 was installed took place on August 10, 1982 and was timed to coincide with the 50th anniversary of the plant.

For the Irkutsk enterprise, this combat aircraft became the first supersonic aircraft produced. The production of the Yak-28 in Irkutsk coincided with the start of production of the An-12 military transport aircraft, which was a real test of strength for a small medium-sized enterprise at that time. In Irkutsk, three versions of the Yak-28 bomber were produced in large series, these are modifications of the Yak-28B, Yak-28I and Yak-28L, as well as the Yak-28U trainer.

Due to the need to install special equipment, the assembly cycle of products was very long. Each complex was assembled separately, after which it was delivered just in time to the aircraft of the modification for which it was planned. During the production of Yak-28 in Irkutsk, technological processes of processing new materials were mastered: titanium, aluminum, magnesium alloys and fluoroplastics. In the aggregate shops, assembly lines were introduced, and in 1962 a special laboratory shop was created for checking and incoming control of finished components.

At the same time, flight tests of the new combat vehicle were particularly difficult. This was due to the design peculiarity of the Yak-28, which had a "zest" in the form of a bicycle-type chassis: the main struts were located under the fuselage, and the wing struts were located at the ends of the wings, all this together with a resettable (angle of attack) stabilizer. Landing of the Yak-28 was carried out immediately on the front and rear chassis.

The Yak-28 was built according to the scheme of a cantilever vysokoplane with a swept wing and tail. The feature was a bicycle-type chassis with front and rear ventral main struts and a pair of additional support struts at the wingtips. At the same time, the rear main landing gear was much shorter than the front one, so the aircraft's parking angle was +6 degrees. The engines were installed in nacelles located under the wing.

Aircraft fuselage - semi-monocoque type, round cross-section; closer to the tail, its shape turned into an oval. The fuselage was sheathed with sheet aluminum alloys. In front of the fuselage was the navigator's cabin, equipment compartment, pilot's cabin and a compartment for the front landing gear. At the same time, the cockpit of the navigator, pilot and the front technical compartment formed a single pressurized compartment. In the central part of the Yak-28 there was a center section, a bomb compartment, fuel tanks and a compartment for the rear landing gear. At the rear of the fuselage were the equipment compartment and the brake parachute compartment. On all modifications of the supersonic aircraft, with the exception of the interceptor (Yak-28P, Yak-28PD, Yak-28PM), the navigator's workplace was located in front of the pilot's seat in the cockpit with a glazed nose. On the interceptor, the pilot and navigator were located one after another and their workplaces were closed by a common movable canopy, and a radio-transparent radar fairing was located in the bow.

Yak-28 in the final assembly shop of aircraft of the Irkutsk Aviation Plant, 1967

To save the crew members, the K-5MN and K-7MN ejection seats were installed on Yak-28 aircraft, respectively, the first for the pilot, the second for the navigator. On the K-7MN ejection seat, there was a special inflatable pillow in the seat bowl that lifted the navigator to ensure the convenience of working with the bombsight. The minimum ejection height for these seats was 150 meters.

The power plant of the aircraft consisted of a pair of R11AF-300 TRDFs, which were soon replaced by the R11AF2-300 engine model. This modification was also installed on the early series of the MiG-21 fighter. The engine automation was to a significant extent similar to that used on the MiG-21 type aircraft (oxygen supply system, start-up automation, anti-icing system). A supersonic air intake with an adjustable cone was located at the inlet of the engine nacelles. The engine power was sufficient to provide the Yak-28 with a maximum speed of 1850 km / h.

The aircraft's fuel system consisted of six fuel tanks, which contained T-1 or TS fuel. On the Yak-28L modification, the fuel supply in the tanks was 7375 liters. In addition, under the wing it was possible to additionally place two outboard fuel tanks, designed for a total of 2,100 liters of fuel. At the same time, the practical flight range was limited to 2070 km.

Yak-28L from the exposition of the museum of the 121st aircraft repair plant, Kubinka

Although the supersonic Yak-28 was an outstanding combat aircraft in its characteristics at the beginning of the 1960s, the pilots treated it with some degree of mistrust. Like any new aircraft that had just been mastered by the industry and put into mass production, the Yak-28 had a fairly large number of hidden defects, both very small and quite serious, which took time to eliminate. Some of the problems were almost mystical. For example, the problem of an aircraft with an asynchronous extension of the flaps was suddenly revealed, and during the tests they could not understand the cause of the problem. This continued until, at one point, the testers accidentally discovered that the compensation plates on the trailing edges of the flaps can simply bend in one direction or another, thereby creating a vortex flow, which "jammed" one of the flaps.

Once, while making a flight from Irkutsk to Moscow, a group of Yak-28 planes overtook another attack: at the same time, all the cars had radio compasses failing. The reason turned out to be quite commonplace - the planes got caught in the rain, and water penetrated into the radio compasses, and when the planes climbed high enough, it simply turned into ice.

All identified problems were promptly eliminated, but the Yak-28 earned the fame initially corresponding. At the same time, as the combat units were saturated with new aircraft, confidence in them and their capabilities grew. Possessing good maneuverability, thrust-to-weight ratio and combat load, the aircraft could solve the combat missions facing it at any time of the day, at any altitude and in any weather. Ultimately, it became clear that for reconnaissance purposes the Yak-28 was a much more versatile and suitable aircraft than the same MiG-21.

For its time, the Yak-28 was good. Possessing the qualities listed above, the aircraft took root in combat units. Over time, Soviet pilots began to practice group actions of Yak-28 aircraft up to and including a division. They trained at any time of the day or night and in any weather conditions. The combat training of pilots and navigators was carried out quite intensively, so the crews of the Yak-28 bombers achieved exceptionally high results in the accuracy of bombing from a high altitude - 12 thousand meters. Such bombing was the main method of using these bombers, which could take up to 3000 kg of bombs of caliber from 100 to 3000 kg into the internal bomb bay. The disadvantages of the aircraft could be attributed only to a short flight range at supersonic speed.

Yak-28U during landing

The aircraft that were used in reconnaissance aircraft were eventually able to prove and confirm their superiority in versatility over the MiG-21R, and in terms of reliability, they also surpassed the Su-24MR reconnaissance aircraft that appeared later, which originally differed in a "raw" complex of reconnaissance equipment. and the Su-24 itself turned out to be quite difficult to control and rather emergency. Even the transition to work from low altitudes did not lead, as one might suspect, to the loss of the combat capability of the Yak-28 supersonic multifunctional aircraft: despite the small suitability for such work of reconnaissance and sighting and navigation equipment, the crews of these aircraft, having developed appropriate techniques, felt confident enough itself when flying near the surface, successfully coping with the assigned tasks. At the same time, these aircraft never took part in hostilities. Only during the Afghan war of 1979-1989 was the Yak-28R reconnaissance aircraft used to a limited extent.

Various modifications of the Yak-28 multifunctional supersonic aircraft were used in units throughout the Soviet Union, as well as in the Western Group of Forces, on the territory of the GDR and the Polish People's Republic, while the aircraft was never exported. Yak-28 served in parts of bomber and reconnaissance aviation, as well as air defense aviation. In Russia, the operation of these aircraft was terminated in 1993, as part of the Ukrainian Air Force - in 1994.