The report states that the weather conditions for the flight from Tabriz Airport to the first and second destinations (Aghband Bridge and Qiz Qalasi Dam) were suitable for visual flight rules (VFR) until 08:50 AM, according to the weather report received from Iran Meteorological Organization on May 19, 2024. However, further investigation is needed regarding the weather conditions during the return flight, based on the latest documents and statements from the pilots and passengers of the other two helicopters.
The majority of documents and records related to the maintenance and repair of the crashed helicopter were thoroughly examined, and no problems that could have contributed to the accident were found.
Based on the conducted investigation and calculations, the helicopter's capacity in terms of passenger numbers and equipment was within the limits of the standard weight at the beginning of the flight, during takeoff from the origin to the destination, and during the return route.
According to the recorded conversations between the flight group pilots, the last contact with the pilots of the crashed helicopter lasted for 69 seconds until the time of the incident, and there was no emergency declaration recorded. This is consistent with the approximate time mentioned in the first report (about 1.5 minutes) when implementing the recorded tape in the MIL-17 helicopter, confirming 69 seconds.
Based on the sampling and tests conducted on the remains and helicopter parts, as well as their distribution and the distances between the separated components from the main body, the occurrence of an explosion resulting from a malfunction during the flight and moments before the collision with the mountainous heights is ruled out.
Throughout the mission and up to 69 seconds before the incident, contact was maintained with the helicopter on the designated frequencies, and the last contact and message were made by the flight group commander (Martyr Mostafavi). Therefore, any disruption in the communication system or frequency interference is ruled out. (It should be noted that communication between the two other helicopters continued until landing at the Sangan Copper Mine.)
According to the reports of specialized experts, no evidence of electronic warfare actions on the crashed helicopter has been observed.
It is reminded that the investigation, testing, and data analysis will continue until the main cause of the accident is discovered, and the results will be communicated.
IRIB