Press TV - Iran says a maintenance program for all 13 aircraft delivered by the ATR company two years ago is on track despite sanctions that have restricted access to technical services from abroad.

National carrier IranAir (Homa) said on Saturday that complicated airworthiness checks for a second ATR turboprop had already finished in a hangar of the company in Tehran.

Mahmoud Naderi, a service supervisor at Homa, said that C-checks, inspections that are carried out every two years and require sophisticated control of majority of aircraft's components, had begun for a third and fourth ATR planes that were built and delivered in 2017.

He told the official IRNA agency that such checks for all 13 ATR planes currently operated by IranAir would finish by March 2020, helping the carrier to keep the planes in service amid sanctions that have affected the aviation sector in Iran.

Iran took the delivery of a total of 13 new ATR 72-600 planes until August last year, a month before the United States imposed a new round of sanctions on the country after leaving a major international agreement on Tehran�s nuclear activity.

The France-based company, co-owned by Airbus and Italy�s Leonardo, has refrained from delivering seven more planes to Iran as part of a deal which came after a previous round of sanctions were lifted in 2015.

However, Homa and other major Iranian carriers have managed to overcome difficulties caused by the sanctions, with reports suggesting that almost no single plane has been grounded due to the bans which have restricted Iran�s access to parts and technical services.

The reported self-sufficiency in the airworthiness of modern planes like ATR 72, which hit the aviation market just in 2010, comes as experts believe sanctions on Iran�s aviation industry have backfired as the country is embarking on an ambitious plan to become an independent manufacturer of civil aircraft.

Iran is already among the 10 leading countries in the world in developing and production of military planes.

Transportation minister Mohammad Eslami said earlier this week that the civil aviation sector in Iran is replicating the success in the military, insisting that the country would make significant progress in developing civil aircraft in a near future.