Sanctions have prevented Iran from procuring new aircraft or equipment, which has been linked to aviation accidents.

The United States-manufactured, two-blade Bell 212 that Raisi was travelling in is believed to have been decades old. Foreign sanctions on Iran dating back to the 1979 revolution, and subsequently over its nuclear programme and its backing of the so-called Axis of Resistance, have made it difficult for the country to obtain aircraft parts or new aircraft.

Since the first US sanctions on Iran 45 years ago, the Iranian economy has continued to take hits, and its airlines have in particular been impacted.

But Iran’s tense geopolitical neighbourhood, and especially its taut relationship with Israel and the US, have also led to deadly errors resulting in the loss of hundreds of lives.

Here is a recap of some of Iran’s biggest aviation accidents since 1979, and how sanctions have affected the sector.

Iran’s biggest aviation incidents

Between 1979 and 2023, Iran witnessed 253 plane crashes that claimed 3,335 lives, according to the Geneva-based Bureau of Aircraft Accident Archives (B3A).

• January 21, 1980: A Boeing 727-100 operated by flagbearer Iran Air struck the slope of a mountain in the Alborz range in Tehran, killing all 128 of its occupants. An inoperable instrument landing system (ILS) and limited visibility due to nighttime and weather are believed to have caused the crash. The accident happened soon after Iranian air traffic controllers ended a strike.
• November 3, 1986: A Lockheed C-130 Hercules operated by Iran’s air force went below the minimum safe altitude of (1,981m) 6,500 feet when the plane struck a mountain slope in the Sistan and Baluchistan province, killing all 103 of its occupants including 96 soldiers. A fault in the altimeter, which is used to measure altitude, might have caused the crash, according to experts.
• July 13, 1988: An Airbus A300 operated by Iran Air was hit by missiles fired by the US Navy cruiser USS Vincennes at Qeshm Island after the ship mistook the plane for a military aircraft. This killed all 290 of its occupants in the deadliest aviation accident in Iran’s history.
• February 12, 2002: A Tupolev TU-154 by Iran Airtour hit a mountain slope in Khorramabad after the crew failed to realise that the plane was off course, killing all 119 occupants including four Spanish citizens. The lack of visibility due to weather was a possible contributing factor.
• February 19, 2003: An Ilyushin II-76 operated by the Islamic Revolutionary Guard Corps (IRGC) hit a mountain near the Kerman airport upon landing, killing all 275 people on the plane. The crew started the descent prematurely and went below the minimum safe altitude in poor visibility.
• July 15, 2009: A Tupolev TU-154 run by Caspian Airlines crashed into an open field in Qazvin after descending rapidly, killing all 168 people on the plane. The crash was attributed to several technical faults such as damaged engine parts and cut hydraulic and fuel lines.
• January 8, 2020: A Boeing 737-800 operated by Ukraine’s flagbearer, Ukraine International Airlines, was shot down by two missiles minutes after takeoff in Sabashahr in Tehran, killing 176 people onboard. The government said this was a “human error” after the aircraft was mistaken for a “hostile target”.

How have sanctions impacted Iran’s aviation sector?

Shortly after the imposition of the sanctions in 1979, the aviation sector of Iran was particularly hit hard after the government was unable to import new planes. Iran suffered from a spike in deadly aircraft accidents through the 1980s, 1990s and the early 2000s.

Central to the US sanctions against Iranian aviation is a bar on the country’s import of any planes or aircraft equipment built with more than 10 percent US parts. That has effectively ruled out the prospects of Iran buying new Western planes or helicopters, but also made it hard for Tehran to source parts it needs for maintenance of its ageing fleets. Some Russian jets also depend on US parts, so sourcing even those is difficult for Iran, despite close ties between Tehran and Moscow, and their shared enmity with Washington.

As of April 2019, 23 Iranian airlines were operating 156 planes out of a total of 300 in the country, suggesting that almost half of the country’s aircraft were unable to fly because of a wait for replacement parts, according to the Washington Institute for Near East Policy.

The frequent need for repairs has raised plane ticket prices in Iran, and has also placed economic strain on smaller aircraft companies. Aircraft also can not be sent abroad for repair and have to be repaired locally, with limited expert manpower, Mohammad Mohammadi-Bakhsh, the head of Iran’s aviation agency, the Civil Aviation Organization of Iran (CAO), told Fars news agency in 2022.

In 2015, the Iran nuclear deal called the Joint Comprehensive Plan Of Action (JCPOA) was signed. In it, Iran agreed to halt the production of materials that could be used in manufacturing nuclear weapons. In return, sanctions on its aviation sector were relaxed, enabling it to buy aircraft from foreign manufacturers such as Airbus and Boeing.

However, sanctions were reimposed when the US left the nuclear deal under former President Donald Trump in 2018. And according to the Washington Institute, the brief period when sanctions had been lifted did not help Iran much: Iran ordered more than 200 aircraft from Western firms in those three years, but received only three Airbus jets and 13 ATR turboprops — smaller planes — before Trump slapped sanctions back on.