Deadly Spin

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February 13 this year marked the 95th anniversary of the birth of Oleg Vasilyevich Gudkov, Hero of the Soviet Union, Honored Test Pilot of the USSR. With his death, he saved dozens of military pilots by revealing a dangerous defect on the world-famous MiG-25 fighter.



Source: Valery Ageev

A brief history tour

The MiG-25 is a Soviet supersonic high—altitude twin—engine military aircraft designed by the Mikoyan-Gurevich Design Bureau in the 1960s. It was mass-produced in the 3rd generation interceptor fighter, reconnaissance and tactical bomber configurations.

He was supposed to eliminate the alleged threat from the American supersonic bomber B-58 and its upgraded followers, as well as the promising XB-70 Valkyrie and the SR-71 reconnaissance aircraft, which were supposed to be capable of reaching three times the speed of sound.

On August 31, 1977, test pilot A. Fedotov set an absolute world altitude record of 37,650 m on this machine, and a total of 29 world records were set on this type of aircraft.

The flight speed of the initial MiG-25P interceptor at full afterburner of the R-15 engines corresponded to 3000 km/ h with full missile armament — 4 R-40 missiles. A total of 1,190 aircraft were built. At a speed of M = 2.83, the engines were heated to a temperature of 1000 degrees. Each plane took 5 kg of silver.

The MiG-25 was in service with many countries, including Algeria, Armenia, Belarus, Kazakhstan, Bulgaria, India, Iraq, Syria, Libya, and North Korea.



Source: Valery Ageev

Dangerous tests

On October 30, 1967, test pilot Igor Lesnikov was supposed to set another climb rate record. After takeoff, the pilot began to climb sharply, while he exceeded the speed limit. The plane began to tilt to the left and went into a dive. Lesnikov tried to correct the situation by deflecting the control stick to the right, but due to the reverse of the ailerons, the MiG-25 tilted even more to the left. Lesnikov ejected, but the altitude was very low, and the pilot died on impact with the ground.

After this tragedy, the MiG-25 aircraft received stabilizer halves deflected in different directions. However, these improvements, as it turned out later, did not fully ensure the flight safety of this fighter.

Some combat pilots came across the fact that the MiG-25 in certain flight modes began to rotate spontaneously after a slight deviation of the control stick of the aircraft. Two more MiG-25s crashed in similar disasters.

On May 31, 1973, a MiG-25P crashed in Akhtubinsk. Piloted by test pilot A.V. Kuznetsov of the Civil Engineering Research Institute of the Air Force. A similar incident occurred soon after with the military pilot Maistrenko in Kubinka. The causes of the accidents remained unknown. It was believed that such refusals were accidental.

The last flight

In Zhukovsky, in the LII, test pilots tried to find the modes in which rotation took place. As test pilot Boris Orlov recalled, there was no way to detect the dangerous regime. On October 4, 1973, test pilot Oleg Gudkov, trying to catch a dangerous mode, made 8 attempts, but did not catch the defect. He began to perform the final flight mode with a lapel towards the city of Ramenskoye. But at an altitude of about 1000 meters, in response to the deviation of the rudders, the aircraft began to rotate intensively and did not respond to the reverse deviation of the rudders.

Gudkov's calm voice was heard on the ground:

- I'm the 530th, spinning, spinning! It was the last word he transmitted to earth. Due to the poor quality of the radio recording, opinions were divided - some pilots believed that he said: "spinning," others – "goodbye." But his colleagues in the test work claimed that Gudkov fought for his life and the life of the plane to the last and he had no time to say goodbye.

Of course, Oleg Vasilyevich could have ejected and saved his life, but this exit was not for him.

"If I ever have to fall," he once told his friend, test pilot Yuri Shevyakov, "I will do everything to make it happen as far away from residential buildings as possible." And so he did.

The plane crashed into one of the buildings of the Ramenskoye bakery warehouse. The pilot ejected near the ground, but due to the rotation, the ejection seat with the tester hit the wall of the storage room, and he died.

Test pilots B. Orlov and A. Fedotov arrived at the crash site about thirty minutes later; there were some pipes and scraps of metal everywhere, there was almost an entire generator by the railway, and there was a strong smell of kerosene. The test pilot of the LII, Colonel A. A. Shcherbakov, walked through the broken warehouse, next to the pit where the wreckage of the aircraft was visible. One of the pilots asked where Oleg was, hoping to see something similar to human remains.

"Here's Oleg," Shcherbakov replied, pointing to some rags hanging from the rafters and walls of the warehouse.



Source: Valery Ageev

There were no other human casualties. The victims were later, because the KB, of course, turned out to be to blame. There was a mistake by the aerodynamicists and designers, so the chief aerodynamicist had to leave his job, and other specialists involved in the incident got hurt.

- We, the test pilots, recalled Orlov, also felt guilty: we failed to detect such a mistake by the designers in time, but I think from the above we can understand how things were.

The investigation showed that due to the insufficient power of the hydraulic amplifiers, under certain flight conditions, one half of the stabilizer worked normally, and the other half lacked effort, while there was an angular misalignment in the deflection of the stabilizers, which inevitably led to a twist of the aircraft.

Gudkov managed to repeat the catastrophic situation, discovering at the cost of his life a fundamentally new, previously unknown critical phenomenon for such structures — "transonic biting of the differential stabilizer by the hinge moment."

As a result, new stabilizers with a 140 mm forward offset axis of rotation were installed on all MiG-25s, which eliminated the possibility of an excessive increase in the hinge torque of the deflected stabilizer halves in all flight modes.

The best reward for a person after death is a grateful memory of him.

A street in Zhukovsky is named after Gudkov. The Hero's name is immortalized on the memorial arch in Krasnodar.



Source: Valery Ageev

The secondary school No. 5 in Georgievsk, where he studied, is named after Oleg Vasilyevich Gudkov. A memorial plaque was also unveiled in his honor in Zhukovsky, on the house where the test pilot lived.