In Ulyanovsk, at the Aviastar aircraft manufacturing plant (a branch of PJSC Il), a person died during cabin tightness tests, four more were injured. The Regional Investigation Department of the ICR opened a criminal case on the fact of violation of labor protection requirements, which negligently caused the death of a person. Experts believe that technology and safety violations could be the cause of the tragic incident.
On Thursday, an incident occurred at the Aviastar aircraft manufacturing plant in Ulyanovsk during testing of the fuselage compartment of the airliner, which is in production, several employees of the enterprise were injured, one died, the press service of the aircraft plant reported. “All four victims were sent to the hospital. The families of the deceased and injured employees will be provided with all the necessary support and assistance from the enterprise,” the press service said.
At Aviastar, the details of the incident are not disclosed, only explaining that “at one of the assembly stages, the fuselage is checked for leaks by pumping excess pressure into the compartments”, “during these tests, a tragic incident occurred.”
The Aviastar Aircraft Building Plant is a branch of PJSC Il (formerly JSC Aviastar-SP, JSC Aviastar, until 1991 – the Ulyanovsk Aviation Industrial Complex). At first, the plant produced An-124-100 Ruslan cargo aircraft, then Tu-204 passenger aircraft, currently the main production line is Il-76MD-90A aircraft (deep modernization of Il-76), Il-78M-90A tankers .
According to Kommersant’s sources, the incident occurred in shop 278 of the assembly plant of the aircraft manufacturing plant. A special team carried out a leak test of the cabin of the Il-76MD-90A aircraft. “But something went wrong, something, I don’t know for sure, was torn off by air pressure, and now a man, a member of the brigade, was killed, four more were injured,” the source said.
Another source from among the employees of the plant says: “There was no external damage to the cab after the incident, it was completely intact. They say that the damage is somewhere inside, but it’s impossible to get close, everything is cordoned off and fenced.”
According to Kommersant’s interlocutors, the most likely reason is a violation of technology. According to them, “five years ago” there was a similar incident at the plant during the An-124-100 cabin airtightness check, but then, fortunately, no one was hurt.
On Thursday evening, the investigative department of the Investigative Committee of Russia (Investigative Committee of the Russian Federation) reported that in connection with the death of an Aviastar employee and the injury of four more employees, a criminal case was opened on the fact of violation of labor protection requirements, which negligently caused the death of a person (part 2 of article 143 Criminal Code of the Russian Federation, up to four years in prison). “It was preliminary established that on March 2, 2023, a 45-year-old worker died during test work, and several more people were injured,” the Investigative Committee of the ICR said in a statement.
Details of the investigation in the Investigative Committee of the ICR are not disclosed. It is not yet known whether the prosecutor’s office will conduct its own check: the department refused to comment on the situation.
An engineer who worked for many years in the assembly production of Aviastar and was directly involved in, among other things, checking the tightness of the fuselage compartments, noted that “according to the technology, if pressure testing and pressure testing are carried out, there must be a fence that provides protection against possible damage in vulnerable places, and people in the testing zone, of course, should not be.”
“All this is spelled out in detail in the technological documents, and it is impossible to deviate from these requirements,” the engineer noted. According to him, in certain cases, when checking the tightness, a person can be inside the cabin, “to look from there, using soap suds, where he can poison the air, and mark with a marker, so that later he can explore and seal this place.” But in this case, the excess pressure should be very small, and this, too, should all be spelled out in the technology of the operation, indicating the permissible pressure value, which should be controlled by the worker using a special pressure gauge. “On his own, without special training, he should not be there,” the interlocutor explained.
He also noted that all devices, hoses, pressure relief valves and the stand must first pass the appropriate verification.
There may be several versions of the causes of the tragedy, according to the engineer. Among them – the accidental supply of too much excess pressure, a malfunction of the devices of the stand that supplies pressure, poor-quality assembly of any fuselage components that could not withstand this pressure.
Aircraft pressurization incidents have occurred in other countries as well. So, in April 1999, at the Tinker AFB Oklahoma City Aviation Logistics Center, during an excess pressure check of the cabin of a Boeing KC-135 Stratotanker military transport aircraft, due to a technology violation and blocked pressure relief valves, pressure was created that exceeded the maximum allowable standards, resulting in an explosion that destroyed the rear fuselage of the aircraft, after which it was no longer subject to repair.