While the death toll reached five, the Interstate Aviation Committee has named the likely reasons of the Tupolev Tu-204 crash at Moscow's Vnukovo airport. Experts say the plane crash may have been caused by a technical failure, bad weather conditions or a human error.

The Interstate Aviation Committee (IAC) reported on Sunday it launched a probe into the Tupolev Tu-204 passenger jet crash that took place at Moscow's Vnukovo airport on Saturday. They analyzed the flight data and information received from the airliner’s voice recorders.

Investigators also seized the plane's flight documents from the offices of Red Wings Airlines that owns the plane. They analyzed the pilots' radio exchange with the control tower, and took samples of the plane's fuel for a probe.

In Saturday's crash landing at the Vnukovo airport, the Tu-204 veered off the runway, crashed into the airport wall, split into three pieces, and caught fire. There were only crewmembers on board the plane.

Experts have named probable reasons of the crash. A malfunction of the Tupolev Tu-204 aircraft combined with difficult weather conditions could have caused the plane crash, a source close to the investigation told Interfax. Yet he did not rule out other possible causes of the crash, including a human factor.

Investigators are considering all possible causes of the accident, including a pilot error, bad weather, and a mechanical failure," the Investigative Committee said.

One of the versions is a failure of the thrust reverser, a source from the emergency response center told Interfax.

"Preliminary findings indicate that, following the touchdown, the pilots used all the deceleration systems available but for some reason the aircraft would not stop and continued to roll. It looks like the thrust reverser or brakes malfunctioned," the source said.

However, the Red Wings company claims that the airline had undergone a planned maintenance check shortly before the accident.

"The last maintenance (B-check) was carried out at the VARZ-400 enterprise on December 14, 2012," Red Wings reported on Twitter.

Likewise, Red Wings owner Alexander Lebedev wrote on his Twitter page that "the plane is new, designed by the Tupolev Design Bureau and manufactured at the Ulyanovsk Aircraft Factory in 2008."

Another version of the crash may be a human error. Yet colleagues of the plane's pilots don't put into question their professionalism and experience and rule out this version, according to Kommersant FM radio station. "They were all professionals dedicated to aviation and just couldn't make a mistake," the pilot’s former colleague told Kommersant FM.

Similar failures were reported on aircraft of this type before in other Russian regional airports. According to Kommersant Daily, at least three planes of the Red Wings company have overshot runaways over the last two months.

The latest incident happened on Dec. 21 when a Tu-204 overshot the runway at Tolmachyovo airport in Novosibirsk. That time the reversals of both engines and elements of the braking system did not turn on. Experts cited "malfunction of the unit of end switches of the main landing gear" as the likely cause of the incident.

Previously, the Federal Air Transport Agency sent a directive to the president of the Tupolev company calling for fixing unstable reverse and braking systems on Tu-204 airliners as soon as possible.

Given the gravity of the incident in Tolmachyovo, the federal agency sent a warning to the president of the Tupolev company.

Despite this warnings and the Saturday crash at Vnukovo, Red Wings Airlines will not stop using Tupolev Tu-204 jets, it said.

"Tu-204 is one of the most reliable aircraft complying with all Russian and international aviation requirements," Red Wings said on its Twitter page.

The company also noted that their representatives are staying at Vnukovo. "Reports that there are no company representatives are at the airport are untrue," the posting says.

Source: RIA Novosti

Meanwhile, investigators confiscated the flight documents of the Tupolev Tu-204 airliner, Investigative Committee spokesman Vladimir Markin said.

As soon as the survivors of the crash feel better, they will be questioned about the circumstances of the crash, he added.

Four people, including the captain, were killed as a result of the plane crash in Vnukovo airport. One of the survivors, flight attendant Tatyana Penkina, died in hospital, thus bringing the death toll to five. Three others severely injured in the accident are still in grave condition. It's uncertain whether they will survive or not. Medical experts described their condition as very serious.

One of the survivors, a 24 year old man, successfully underwent surgery at the Sklifosovsky Emergency Medicine Research Institute.

"I believe and I hope that his life is out of danger," Anzor Khubutia, the head of the institute, told Interfax on Sunday.

The article is based on materials from Interfax and Kommersant FM.