On the afternoon of May 23 local time, the funeral of Iranian President Lehi will be held in his hometown Mashhad. The day before, the official condolence activity was held in Tehran, and Iran's supreme leader Ayatollah Ali Khamenei presided over the prayer. When the hearse carrying the coffins of Leahy and others drove into the street, the road was full of Iranian people on both sides.
On May 21, in East Azerbaijan Province of Iran, a farewell ceremony was held for the bodies of the victims, including President Leahy of Iran, in Tabriz City. Picture/Vision China
On May 19, Leahy went to the border area between Iran and Azerbaijan to attend the completion ceremony of the Gizgalasi Dam. On the way to Tabriz City, East Azerbaijan Province after attending the event, Lehi's Bel-212 helicopter lost contact in the fog. After more than ten hours of searching, rescuers found the wreckage of the helicopter in the Alasbalan Mountains to the north of Tabriz City. All nine people on board, including Leahy and Iranian Foreign Minister Abdullahian, were killed.
"People are puzzled and shocked." Hagpana, a senior researcher at the Tehran Institute for Strategic Studies (RISS), told China Newsweek that many Iranians have expressed their doubts these days: why is the president's travel plan so poorly formulated? What on earth caused such a serious disaster?
As Hussain, the director of the President's General Office who traveled with Leahy in another helicopter, announced more details of the accident to the media, combined with the scene debris images released by the Iranian media, and the analysis of the air crash investigators, people could gradually sort out a relatively complete story. However, the specific cause of the accident still needs official investigation.
A portent of danger
38 ° 45 ′ 57 ″ north latitude and 46 ° 43 ′ 43 ″ east longitude are the coordinates of the last return signal of the Bell 212 helicopter issued by the Iranian National News Agency. 38 ° 46 ′ 4 ″ north latitude and 46 ° 41 ′ 33 ″ east longitude are the heat source targets found by rescue helicopters sent by the Turkish Ministry of Defense. A few hours later, the rescue team found the relatively complete tail and the main body wreckage burned down by the fire here.
Mark the above two coordinates on the global aeronautical chart information data website Sky Vector, and you can see that they are located on both sides of a north-south winding valley that runs through the Alaskan Balan Mountains. The valley extends northward to the Alas River on the border between Iran and Azerbaijan.
At about 1:00 p.m. local time on May 19, Lehi and Azerbaijani President Aliyev jointly attended the inauguration ceremony of the Gizgalasi Dam on the Alaska River, and then took the Bel-212 helicopter to enter this valley. When arriving near the two coordinates mentioned above, the helicopter had already passed about one third of the way from the bank of the Alas River to Tabriz, a city in northwest Iran, and was about to fly out of the Alasbalan Mountains.
On May 19, in the border area between Iran and Azerbaijan, Iranian President Lehi (first from left) and Azerbaijani President Aliyev (second from left) attended the inauguration ceremony of the Gizgalasi Dam.
It seems to be a safe journey. The Bel-212 helicopter is equipped with two security personnel and a three person crew, consisting of two colonel pilots and a major aviation engineer from the Iranian army aviation. The day before, they sent the President to the dam. This time, their task is to send the President back to Tabriz, 130 kilometers away. Outside the Alasbalan Mountains, the terrain for the rest of the voyage was relatively flat.
For the Bell 212 helicopter, which can be piloted by one person and is famous for its reliability, this is a luxury staffing. This type of helicopter is transformed from the US military helicopter during the Vietnam War. Since 1979, it has been regarded as one of the most reliable helicopters in the world. Bell's official website claims that this type of helicopter "operates reliably in some of the most extreme weather conditions around the world every day".
There were also two Soviet made Mi-171 helicopters in the same fleet, taking officials such as Minister of Energy Mehrabian, Minister of Transport Bazpash, and President General Office Director Hussein. Foreign Minister Abdullahian and the Governor of East Azerbaijan Rahmeti originally planned to take one of the Mi-171, but eventually accompanied Lehi to board the Bel-212.
Iranian media have released many historical images of Lech taking the Mi-171 helicopter, and there is no official report explaining why he changed to Bell-212 this time. However, on March 23, 2023, a Mi-171 helicopter taken by the Iranian Sports Minister crashed out of control when landing at the Baft Stadium. The Minister survived and the office director was killed.
In addition, this Bel-212 may have been specially modified. Turkish media T ü rkiye quoted "Iranian security sources" as saying that Lehi's Bel-212 was equipped with a wealth of navigation and positioning equipment. In addition to the standard GPS system and transponder, there was also a special device that could send signals without interruption for 72 hours.
The Iranian media did not confirm this detail. Daniel Ajkum, an expert in air crash investigation, pointed out to China Newsweek that if extreme weather is superimposed in mountainous areas, the signals of these additional navigation and communication systems will still be affected or even blocked, which may cause pilots who cannot accurately determine the location to drive helicopters to mountain walls and other obstacles. At this time, the terrain anti-collision and early warning system that can detect obstacles and send out alarm sounds is particularly important. However, at present, there is no information indicating that the Bel-212 on which Leahy is riding is equipped with a terrain anti-collision and early warning system.
These problems seem to be a worry: when we took off at 1 p.m. on the 19th, it was cloudy, but our vision was good. Previously, the Iranian Meteorological Organization issued an orange alert for the whole region, but there was no sufficient public information on whether the meteorological information received by the crew when formulating the flight plan was accurate.
According to the data of Sky Vector, the Iranian Civil Aviation Meteorological Station, which is the nearest to the Alabama Mountains, is in Tabriz, the end of the journey. In addition to some villages and towns with more than 100 people, there are large forests and no man's land in the continuous valley. It is unclear whether the Iranian air force has more accurate meteorological data in this area.
Information about the crash of Iran's president.
The Federal Aviation Administration (FAA) once pointed out in the mountain flight manual that changes in mountain microclimate are often unexpected, and one of the most reliable ways is to ask pilots who have just flown the same route. But in this accident, the crew of the three helicopters were the people who "just flew over this route": they had just sent the President and his party to the dam the day before, and the weather was fine all the way.
Ajikum said that when flying in mountainous areas, helicopter pilots should take full account of the need to cope with instrument meteorological conditions (that is, visibility cannot pass visual flight) in rainy and foggy weather. According to a 2021 report of the American Academy of Aeronautics and Astronautics, 28% of all fatal helicopter crashes are weather related.
In 2006, a Bel-412 helicopter (an upgraded version of 212) of Mercy Airlines crashed near the Cajon Pass in southern California. The survey report shows that the Kahong Mountain Pass is famous for strong wind, turbulence and fog. At that time, the pilots encountered "intermittent fog", and suddenly entered the unexpected instrument meteorological conditions from the clear visual meteorological conditions.
The pilot involved in the Compassion Air Accident had 12 years and 3000 hours of flight experience as a US military helicopter pilot, but he failed to avoid tragedy. Ajikum pointed out that even experienced pilots may still feel nervous when encountering a dangerous situation of fog if they do not maintain the ability to check the instrument flight within six months. "If you are carrying extremely important passengers, the pilot will also face invisible psychological pressure."
From the public information, the Bel-212 helicopter crew may have not performed such an important task for a long time. Based on the reports of the Iranian National News Agency on Lehi, he mainly attended activities near the capital Tehran in the past year, and rarely set foot in remote areas. When visiting abroad, he took a special government plane refitted from a civil aviation airliner. The pilots of the special plane came from the Iranian air force, not the army aviation.
The death cloud that cannot be traversed
About 45 minutes after takeoff, a formation of three helicopters marched about 50 kilometers in the valley of Alaska. President's General Office Director Hussein sat on one of the Mi-171. He recalled that the president's plane was in the middle and two Mi-171 aircraft were escorting on both sides. Captain Mustafawi of Bel-212 suddenly asked the formation to climb up and cross the clouds.
Two Mi-171 planes quickly passed through the clouds. Thirty seconds later, they noticed that the Bell 212 helicopter, which was supposed to be in the middle of the formation, disappeared. The Mi-171 crew then circled back to try to find the president's plane, but there was no result in visual and radio contact. Due to the existence of clouds, they could not immediately descend, so they had to continue flying to a nearby copper mine to land. The rescue work immediately began.
According to the operation manual of Bell Helicopter, Colonel Mustafawi's decisions and instructions are normal: when accidentally entering the instrument meteorological conditions with dense clouds and low visibility, the pilot should accelerate to the climbing airspeed, then immediately climb above the clouds, and then contact ATC to report the emergency.
The problem is that during the climb, the pilot also needs to complete many tasks at the same time: maintain the attitude control and heading control of the helicopter, pay attention to avoiding mountains and other obstacles, avoid accelerating too fast or turning too far, which will lead to loss of control, and pray that there will be no turbulence, windshear and other emergencies to "shoot" the aircraft to the ground.
Ajikum pointed out that one of the possible reasons for the successful climb of Mi-171 helicopter and the accident of Bel-212 is the different power of the aircraft. "These Soviet made helicopters are designed for extreme conditions in high mountains. They have powerful engines. The Bel-212 helicopter will struggle with power in high altitude areas due to its poor performance."
In 2021, the Canadian Traffic Safety Commission wrote in an investigation report on the Bel-212 helicopter crash in strong airflow in mountain areas that, considering the lack of power, pilots must pay attention to the airflow and wind speed during climbing when encountering extreme weather conditions such as mountain fog. "If the helicopter is in downdraft, do not try to climb immediately, because your helicopter may not be able to do this. You should avoid downdraft as soon as possible, find the nearby updraft and climb again," the report wrote.
However, this means that the helicopter will fly longer in the clouds, and the pilot may have "space disorientation": without visual reference, the posture and orientation of the body feel are different from the information of the instrument, "clearly turning, but the body feel is flying straight".
The only solution is to absolutely trust the instrument. But what if the navigation system itself fails? Ajikum once presided over the investigation of helicopter accidents. He said that the first thing he would do was to check the wreckage parts and maintenance records to confirm or exclude this possibility. It is worth noting that on May 20, the Iranian National News Agency mentioned in its report that the cause of the helicopter crash was related to technical failure.
It can be determined that if the two coordinates released by the Iranian media and the Turkish UAV are accurate, the helicopter will deviate from the route to the northwest for a short period in the final stage. At present, it is impossible to know whether this is to avoid downdraft, or whether the pilot found the wrong direction due to "space disorientation" or navigation failure. In a word, in the clouds, Bel-212 finally deviated from its due course and hit the mountain higher than the flight altitude.
The wreckage site shows the final fate of the aircraft: the plane hit the hillside head-on at a low airspeed, and the engine, transmission device and other heavy objects arranged on the top of the helicopter fell down due to gravity. The passengers trapped in the cabin have no chance to escape. The impact ignited the fuel tank, and the fire gradually engulfed the debris.
Only Al Hashim, a senior cleric in East Azerbaijan Province, may have survived because he was thrown out of the broken fuselage during the impact. When people on the other two helicopters called Mustafawi, the Bel-212 pilot, on his mobile phone, Hashim answered the call. He said that he was in the woods and could not distinguish anything around him. "The situation is very bad". The contact was then interrupted. More than ten hours later, rescuers found Hashim, who showed no signs of survival. As for the other eight people, Hussain, the director of the President's Office, disclosed that they were all "killed on the spot".
Ajikum pointed out that the air crash was probably the result of the superposition of natural, mechanical, technical, human and other factors. "We can roughly infer that the pilot may lose his way, have technical problems, or have some improper handling, and finally hit the hillside under bad weather conditions. This is a relatively reasonable explanation."
Before the official investigation report was released, the outside world could not confirm the specific cause of the crash of the Bell 212 helicopter. According to the practice of the civil aviation industry, the United States, as the country of registration of aircraft manufacturers, can send its traffic safety committee (NTSB) to participate in the accident investigation. The US State Department said on the 20th that after the accident, Iran had asked Washington to assist in the rescue and search work, but because of the "arrangement and coordination" problem, the US was unable to help.
Iran may also seek help from professional institutions in other countries. In 2020, after the Ukrainian International Airlines flight PS752 was hit and crashed by the Iranian military in Tehran, Iran sent the black box to France, but the work of the French Aviation Safety Agency was limited to reading data, without investigation and analysis. Five months after the accident, the Iranian Civil Aviation Organization released a preliminary report. In March 2021, Iran issued the final report on the crash, and the process and cycle were in line with the prevailing standards of the international civil aviation industry.
Reporter: Cao Ran, Chen Jialin
Editor: Xu Fangqing
