Ukraine International Airlines Flight PS752

A normal flight prepared in an abnormal setting

Ukraine International Airlines flight PS752 was scheduled to leave Tehran Imam Khomeini airport for Kyiv Boryspil on 8 January 2020. The aircraft was a Boeing 737-800 registered UR-PSR, carrying 167 passengers and nine crew members. Iran's Aircraft Accident Investigation Board reported that the aircraft was airworthy and the crew appropriately qualified. Its account describes a civilian departure within a period of heightened military alert. The technical report and the official responses disagree about how adequately the investigation explained that setting and the decisions made within it. This account attributes those positions rather than turning either government's explanation into an independently established finding.

The departure was later than its scheduled time. The Iranian report records removal of cargo to bring the aircraft within the permitted takeoff weight. The crew sought startup clearance at 05:51 local time, and the tower initially asked them to wait while coordination took place. The report describes a military coordination process through the area control centre, followed by startup and pushback approval at 05:55. These details establish that the flight went through the departure-clearance process described by investigators. They do not establish that the process eliminated the risk of a military unit treating a cleared flight as hostile.

All times in this account follow the report's Tehran local clock, three hours and thirty minutes ahead of UTC. The report cautions that some reconstructed timings have uncertainty of about two seconds. Clearance was given for the planned departure, and PS752 took off from runway 29 Right at 06:12. Iran AAIB later found the flight path and altitude normal and said civilian flight operations did not contribute to the air-defence misidentification. That finding is kept separate from the question of whether the airspace should have remained available for such operations.

The launch sequence described by Iran

Iran AAIB described an air-defence unit that had been moved a short distance before the flight. According to the report, the unit's heading was not correctly realigned to north, producing an error of about 105 degrees in its interpretation of targets. The report used this error to explain why a departing civil aircraft could be perceived as an approaching threat. Iran AAIB said it had seen confirming evidence and cross-checked military information against recordings and other observations. This is the Iranian investigation's reconstruction of military activity. It is not presented here as an independently verified explanation, because the Canadian response specifically challenged the absence of supporting evidence made available for that scenario.

The report stated that a message concerning the target did not reach the coordination centre and was not recorded there. It described the operator acting without the required command response and launching the first missile at 06:14:39. A second launch was reported at 06:15:09. The final findings attributed the first warhead's detonation near the aircraft to about 06:14:56. The report's individual reconstructed times should be read with its stated uncertainty rather than as proof of an exact second-by-second sequence beyond the evidence. The distinction matters when aligning missile events with recorded aircraft failures.

Canada's TSB said that launcher misalignment and a launch without permission were a plausible explanation, but that Iran had provided no evidence supporting this scenario. Its response identified missing detail about calibration, the operator's training and proficiency, communications failures and supervision of field operations. The TSB also disagreed with the proposition that military activity fell outside the safety investigation's scope. These criticisms do not establish a different launch mechanism by themselves. They identify weaknesses in the explanation offered and questions that the Canadian authority considered essential to a credible preventive investigation.

Aircraft evidence after the first detonation

The first detonation coincided with the end of flight-data recording and loss of secondary radar and ADS-B signals. Iran AAIB linked these changes to damage from the missile warhead. Other evidence showed that the aircraft did not immediately cease all movement or all recording. The cockpit voice recorder continued for a short period, and primary radar information supported continued flight followed by a right turn. This distinction prevents a misleading account in which loss of one recorder is treated as immediate ground impact. The report reconstructed progressive damage using multiple sources rather than a complete uninterrupted flight-data record.

The Iranian analysis associated later changes in the cockpit recording with disruption of electrical supply. It also reported crew voices after the first impulse and inferred that the cockpit crew remained alive at that stage. These findings do not support an invented account of what the passengers experienced or what unrecorded decisions followed. Nor does the record permit a fully resolved reconstruction of every aircraft system. The surviving recording is a limited piece of the sequence, and the narrative uses it only for the timing and technical conclusions the investigation itself drew.

Iran AAIB concluded that structural integrity was maintained until ground impact at about 06:18:23 near Khalajabad, in the Shahriar area southwest of Tehran. All 176 occupants died. It attributed the loss to damage caused by the first missile detonation and a cascade of subsequent failures. The report considered the second missile likely ineffective, while retaining uncertainty about whether it had any effect on the aircraft. That qualification remains explicit. Two launches do not, by themselves, demonstrate two confirmed damaging strikes, and an account should not erase uncertainty merely to produce a simpler sequence.

Airspace risk and the limits of clearance

The report described Iranian military and civilian measures taken after Iran's missile attacks on targets in Iraq and in anticipation of a possible response. These included restrictions on some western air routes and military approval for departures from civil airports. Iran did not close all its airspace to civilian aircraft. The AAIB's analysis distinguished risk assessments based on relatively stable conditions from rapidly changing circumstances. It found that implemented mitigations did not prevent the error that occurred. Its contributing-factor discussion therefore extends beyond the missile unit to the effectiveness of the protective layers around civilian operations.

TSB asked why airspace remained open during heightened military alert and why airlines continued to operate. Its published response acknowledged the restrictions and approval arrangements described by Iran, but said that the report only partially explained those decisions. TSB also stated that Iran had not issued notices warning aircraft operators of the relevant hazards before the shootdown. It noted that other aircraft had departed Tehran during the same period. This is an official Canadian critique of risk communication and airspace management, not a claim that PS752's crew alone could have identified and corrected the military situation.

The distinction between permission to depart and adequate risk protection is central to the official material. A clearance records an operational authorisation, while the investigation's preventive question concerns whether military and civil systems could reliably protect that authorised flight. Iran AAIB described coordination and proposed improvements to warning processes. TSB said the report did not explain the underlying factors behind the missile launches. Both discussions concern safety barriers, but they differ sharply over whether the available explanation was sufficient to show how recurrence would be prevented.

Participation, translation and Ukrainian responses

The report describes participation by Ukraine as the aircraft's state of registration and operator, alongside other involved states and technical organisations. Canada's role was more limited than that of an accredited representative. TSB said its investigators visited the accident site and attended recorder-readout activity, but were not allowed to listen to cockpit recordings or directly access flight-data recordings. It later assisted Ukraine in reviewing the draft report. Those limits matter when interpreting Canada's critique: its response is an official assessment of the investigation and information available to it, rather than a separately completed parallel accident report.

Ukraine's accident investigation bureau published a notice on 26 February 2021 confirming that its experts had studied the draft and submitted comments and remarks to the Iranian investigator. The cached notice is evidence of participation in consultation; it does not publish the full technical comments. A later joint statement, published by Ukraine's government on 5 July 2023, said Canada, Sweden, Ukraine and the United Kingdom had filed an application before the International Court of Justice. The states alleged failures of prevention and of transparent, impartial criminal investigation. Those allegations are attributed to the issuing states and are not treated as adjudicated facts.

The primary report used here is the official English edition hosted by ICAO. Its foreword states that the translation is supplied as a courtesy and that the Farsi version is the reference document. The cover retains a draft header, while the title, issue sheet and body identify a final report; TSB's March 2021 response likewise identifies Iran's final report. These documentary details are disclosed rather than silently corrected. The full Ukrainian technical comments and an inaccessible March 2021 diplomatic response are not reproduced or paraphrased from an unofficial substitute.

Recommendations and questions left unresolved

Iran AAIB recorded changes to warning and risk-assessment arrangements and issued recommendations concerning prompt hazard information, dynamic risk assessment and civil-military coordination. These are the actions and recommendations described in the final report, not a verification that they now operate effectively. TSB said unspecified military corrective actions could not be assessed from the report and that the recommendations did not specifically address the missile launches. Its response called for greater credibility and transparency in investigations involving military activity, including review of the international investigation framework.

The official sources establish a fatal civilian flight, missile launches and the Iranian report's attributed damage mechanism, while leaving substantial disagreement about the underlying explanation and preventive response. This account does not infer intent, assign individual criminal guilt or report a present outcome of international litigation. Its purpose is to make the technical findings, their evidential limits and the official criticisms readable together, with enough distinction that a reader can see which authority made each claim and which questions that authority considered unanswered.