Iran says Boeing jet tried to turn back before crashing

The Boeing Co. 737-800 jet that crashed in Tehran Wednesday killing 176 people tried to turn back soon after takeoff before plunging to earth in a fireball, Iran’s Civil Aviation Organization said in an initial report.

Ukraine International Airlines Flight 752 disappeared from radar screens at 8,000 feet (2,440 meters), and witnesses said they saw it on fire in the air, according to the report. The flight-data and cockpit-voice recorders were both damaged but their core memory appears to be accessible, it said.

The findings are some of the first officially released from a probe set to be fraught with difficulty and intrigue amid heightened tensions between the U.S. and Iran. American agencies including the National Transport Safety Board are weighing whether it’s legal to engage with Iranian authorities under terms of sanctions against the country, according to people familiar with the matter. They’re also concerned about sending people to Iran given recent military strikes.

Iran has invoked an international agreement to get assistance from other countries, including the U.S., in the investigation. A Ukrainian team had arrived in Tehran, Iran’s Ministry of Roads and Urban Development said Thursday. Eleven Ukrainians died in the crash, including all nine crew. There were also 82 Iranians and 63 Canadians, as well as Swedes, Afghans, Britons and Germans on the plane, which was delivered new to the airline in 2016.

Conflicting signals have emerged about what might have caused the Kyiv-bound jet to plunge from the sky near Tehran minutes after taking off. Iranian authorities initially blamed technical issues and then an engine fire. The Ukrainian embassy in Tehran ruled out terrorism before amending its statement to offer no comment on possible causes. Ukraine International said it didn’t “even consider” the possibility of crew error.

The crash came hours after an Iranian missile attack on two Iraqi military bases in retaliation for an American drone attack last week that killed one of Iran’s top generals. American forces are stationed at both bases.

Under the United Nation’s International Civil Aviation Organization, crash investigations are conducted by the nation in which they occur. In addition, the country where the plane and key components are manufactured are allowed to take part. Television footage showed debris from the plane scattered over charred, flat landscape. Weather conditions appeared clear.

Iran notified the UN agency of the accident in the hours after it occurred, according to the people, who were briefed on the matter but weren’t authorized to speak about it and asked not to be named. The recently serviced, three-year-old jet went down without a distress call and after its global-positioning transmissions were cut off mid-air, which is unusual for a crash.

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A video purportedly shot by a bystander shows flames coming from the jet as it streaked across the night sky and burst into a fireball on impact. “The plane is on fire,” an unidentified male can be heard saying. “In the name of God, God help, call the firefighters.”

An emergency locator transmitter was activated, the crash report said, meaning a satellite transmitter antenna was detached from the plane during its descent.

The NTSB routinely participates in dozens of crash investigations around the world under the ICAO process, known as Annex 13.

By notifying ICAO, Iran suggested it might be open to U.S. help in the probe, said the two people. But the Islamic Republic has sent mixed signals, with some officials being quoted as saying they would not allow Americans to analyze the plane’s two crash-proof flight recorders, for example.

American law also prohibits the NTSB from working in Iran because of longstanding bans on conducting business in that country. The NTSB has occasionally assisted in accident investigations there, but had to obtain special permission from the U.S. Treasury. The process of obtaining such approval has at times taken more than a year.

“The NTSB is monitoring developments surrounding the crash of Ukraine International flight 752 and is following its standard procedures for international aviation accident investigations, including long-standing restrictions under the country embargoes,” the agency said in an emailed statement Wednesday.

“As part of its usual procedures, the NTSB is working with the State Department and other agencies to determine the best course of action.”

The State Department issued a statement offering assistance to Ukraine, but notably didn’t mention helping Iran. “The United States calls for complete cooperation with any investigation into the cause of the crash,” the department said.

Despite early reports from Iran suggesting an engine fire might have led to the crash, some aviation safety experts said the plane’s sudden fall as it apparently was engulfed in fire might have been from a bomb or missile. One veteran aviation accident investigator said the flight-tracking data and amateur video were unlike typical engine failure or fire scenario.

“Airplanes don’t just catch fire and have that fire spread like that in such a short period of time, unless there was an intentional act causing that fire and explosion,” Jeffrey Guzzetti, former chief of the U.S. Federal Aviation Administration’s accident investigation division said in an interview.

The aircraft climbed normally until it reached an altitude of 7,900 feet (2,408 meters), then suddenly stopped transmitting its position, according to data from the tracking site FlightRadar24.

Theories

The tragedy evoked memories of the 2014 downing of a Malaysia Airlines jet by a surface-to-air missile during the conflict in Crimea, eventually blamed by investigators on pro-Russia rebels. Ghasem Biniaz, head of communications for Iran’s Ministry of Roads and Urban Development, said reports of a missile attack are false, state-run IRNA reported.

The Ukraine International jetliner was equipped with a device that communicated with the airline and it showed the plane was behaving normally until it stopped transmitting at about the same time, said a person familiar with the data.

If the amateur video is genuine, it indicates that the plane was essentially a fireball as it plunged, Guzzetti said. Bright lights emanating from the aircraft suggest explosions as well.

Two other aviation safety experts were cautious about jumping to conclusions.

“I wouldn’t take anything off the table right now,” said John Cox, a former airline pilot who is president of Safety Operating Systems. When asked about the potential for a bomb or missile, Cox said, “Certainly they are going to look at external forces.”

“Accident investigations should stand above politics,” Cox said. “I’m hopeful that all the governments will put politics aside and let a transparent accident investigation take place.”

Ukraine International said in a statement that the investigation would include representatives of Iran, Boeing, the airline and the National Bureau of Air Accidents Investigation of Ukraine.

It’s at least theoretically possible for a fast-moving cargo fire to take down a plane, said Roger Cox, a former NTSB investigator. A ValuJet plane crashed in Florida in 1996 after pure oxygen caused a raging inferno, he said. But in that case, the plane flew for about 10 minutes, far longer than the Ukrainian jet.

The tragedy strikes during a deeply challenging period for Boeing, which is gripped by one of the worst crises in its 103-year history. Deadly crashes involving the company’s 737 Max in Indonesia and Ethiopia led to the global grounding of the jet in March, and the manufacturer is still struggling to get it back into service.

Wednesday’s crash involved the predecessor to the 737 Max that doesn’t use the same flight control system implicated in the Indonesian and Ethiopian crashes. The 737-800 has one of the best safety records or any jetliner. This was also Ukraine International’s first crash since it was set up in 1992.

Engines for the single-aisle plane are made by CFM International, a joint venture of General Electric Co. and Safran SA. A representative didn’t comment on the details or possible cause of the crash but said by email that CFM extends “heartfelt sympathies to the families and loved ones of those on board.”