Iranian President Ebrahim Raisi was on a US-made Bell 212 helicopter on Sunday when the aircraft crashed near the northwestern city of Tabriz.
Neither Raisi, nor any members of his accompanying delegation, emerged from the wreckage of the helicopter, which Iran procured decades ago from the US before the 1979 Iranian revolution.
The Bell 212 was first manufactured in Fort Worth, Texas, before its factory was moved to the Canadian city of Mirabel, Quebec in 1988, with production ceasing in 1998.
Although the aircraft made its first flight in 1968 for military purposes, its durability and ease of use made an good choice for civilian transportation.
The Bell 212 has the capacity to carry up to 15 passengers, including the pilot.
It can serve in firefighting missions, as well as cargo transport and armed reconnaissance.
Raisi's helicopter was reportedly modified to carry 15 passengers.
Technical specifications
The Bell 212, which can be flown with either one or two pilots, is 17.41 meters (about 57 feet) long, with a height of 3.83 meters from the ground.
It weighs 2,962 kilograms (6,525 pounds) when empty, with a maximum takeoff weight of 5,080 kilograms and is powered by a 1,300-kilowatt engine with two rotors, each 14.63 meters long.
The helicopter normally flies at a speed of 118 miles per hour (190 kilometers) but can reach up to 137 miles per hour in combat flight.
It can travel up to 273 miles and operate at a maximum altitude of 17,388 feet.
Maintenance, spare parts shortages
Iran has faced difficulties maintaining US-made weapons and vehicles due to years of embargoes that have also caused spare part shortages.
The crashed Bell 212 helicopter is estimated to be at least 30 years old and it is believed that Iran's military have 10 of its type in its inventory.
