PS752 Probe: Foreigners Invited, Even As Wreckage Is Cleared

The Ukraine International Airlines Flight 752 (PS752) investigation appears headed for a major impasse as Iranian officials welcome international aircraft accident investigation experts to Tehran, even as they remove vital evidence of the Boeing 737’s wreckage and deny claims by foreign intelligence sources that the aircraft was shot down.

Iran’s Aircraft Accident Investigation Board (IAAIB) on Jan. 9 extended invitations to key international agencies, including Canada’s Transportation Safety Board, France’s BEA, and the U.S. NTSB to designate representatives to assist in the probe of the Jan. 8 crash near Tehran. Levels of participation are unclear, however. BEA stressed that it was not sending any investigators to Iran at this point, contrary to some media reports. Participation by technical experts from the U.S., including Boeing, would require approval from the U.S. Treasury Department’s Office of Foreign Assets Control. Boeing said Jan. 10 it was working with OFAC.

IAAB’s invitations align with its pledge, made in an initial accident briefing issued Jan. 9, to follow ICAO protocol in leading the probe. But reported activity at the accident site—an open area in Tehran’s suburbs—cast doubt on Iran’s transparency. Several news outlets and satellite images showed workers clearing the wreckage by hand and with heavy machinery.

ICAO guidance is clear: wreckage should not be moved for non-safety reasons until investigators have gathered all available evidence.

“The wreckage should be left undisturbed until the arrival of the investigation team,” ICAO’s Manual of Aircraft Accident and Incident Investigation explains. “In general, disturbance of the wreckage shall be limited to that necessary to rescue survivors, extinguish fires and protect the public.”

Word of the wreckage clean-up comes on the heels of several foreign governments—including Canada, the UK, and the U.S.—citing evidence indicating PS752 was downed by an Iranian surface-to-air missile. Iranian officials denied the allegations.

“The thing ... that we can say with certainty is that this plane was not hit by a missile,” Iran Civil Aviation Organization director Ali Abedzadeh told reporters in Tehran Jan. 10. 

Iran’s version of events: a technical problem with the aircraft soon after departure from Imam Khomeini International Airport (IKA) caused a fire that spread quickly and brought the 3.5-year-old 737-800 down as it was attempting to return to IKA. Iranian officials have not offered any evidence to support its theory beyond eyewitnesses that saw the aircraft on fire, and a flight path that turned away from its scheduled route to Kyiv soon before it crashed.

On Jan 9, Canadian Prime Minister Justin Trudeau, citing “intelligence from multiple sources,” including Canada, became the first foreign leader to point a finger at Iran. “The evidence indicates the plane was shot down by an Iranian surface-to-air missile (SAM),” he said.

Ukrainian Security Service head Ivan Bakanov said Jan. 10 that his agency was looking at two scenarios: terrorism or a missile strike, the Kyiv Post reported.

Earlier, Ukraine National Security and Defense Council Secretary Oleksiy Danilov said his investigators planned to search for evidence that a Russian-made Tor M1 SAM missile was used, citing images on social media claiming to show fragments, including an intact nose cone, in the vicinity of the crash.

Russia developed the Tor M1 SAM system to defend mobile targets from low-flying aircraft and cruise missiles, explained Michael Kofman, senior research scientist at the Center for Naval Analyses. This requires being able to fire within moments of spotting a target, which limits the number of checks and balances it has compared to similar systems, such as the Russian S-300PMU, designed to protect critical infrastructure.

Iran has Tor M1s, but unlike Russia, uses them for critical infrastructure protection, Kofman said. 

A Tor M1 operator has three sensors to find the target: a search radar, electro-optic camera and an IFF interrogator. All three are capable of identifying and discriminating between a 737 and a military aircraft or cruise missile, he said.

The system’s missile is guided to the target by a fire control radar or its electro-optic camera as a back-up. It does not have active guidance, Kofman said.

The Tor M1 is designed to fire in salvos of two missiles to increase the probability of kill, he added. The warhead is in the middle of the missile, making it more likely the nose cone and tail section would survive a strike.

A video published soon after the disaster claimed to show a missile hitting PS752. Investigators at open-source intelligence specialists Bellingcat geo-located the video to a location near the accident site and verified that its orientation matched the aircraft’s flight and surrounding buildings.

U.S. intelligence sources told the New York Times that they detected “multiple” missiles fired at the aircraft. 

PS752 departed IKA nearly an hour later than scheduled, and several hours after Iran launched a ballistic missile attack from inside the country on U.S. forces based in Iraq. The strike was in retaliation for a U.S. attack on Iranian military personnel in Baghdad Jan. 3. 

Iranian officials have not said whether their military was on high alert following the attack on U.S. forces, or if any assets were deployed to guard key infrastructure.