The mid-air horror ended after the passengers safely landed at Tehrans Mehrabad Airportwith no injuries.
A committee has been formed to examine the cause of the incident which happened during the jumbo jets flight from the Iranian capital to Bandar Abbas with 426 people on board.
The committee will carefully examine the cause of the technical failure, head of the engineering and safety office of the Civil Aviation Organization (CAO) Mohammad Shahbazi said.
Prior to departure, all necessary checks had been conducted on the plane but during the flight, engine number 3 of the plane faced technical malfunction and a piece of the engine came off, he said.
Thanks to the pilots prudence, the plane fortunately returned to Mehrabad Airport with no injuries to passengers, Shahbazi said.
The passengers were flown to Bandar Abbas on two back-up flights, he added.
Deputy head of Mahan Air Faramarz Sarvi said the aircraft was among the private airlines modern airliners in service since about 1990.
[caption id="" align="alignnone" width="555"]
Local people have gathered around a piece of engine from a Boeing 747 near Eslamshahr south of Tehran. Tasnim[/caption]An Iran-140 with 48 people on board crashed near Mehrabad Airport in August 2014, killing at least 39 people.
Iranian airlines have been plagued by a series of crashes because of Western sanctions which block the country from buying parts and renovating its ageing fleet.
The July conclusion of nuclear talks and an imminent lifting of the sanctions has raised hopes of abuying spree by Iranian airlines.
Boeing has said it was seeing a good opportunity for business in Iran, citing its long history in the country.
Iranian officials have said the country would need between 400-500 new aircraft worth at least $20 billion to renovate its aging fleet and that initial negotiations have begun with the likes of Boeing and Airbus.
Were still waiting on getting the go-ahead from our government to still even have those kinds of discussions, Boeing Vice Chairman Ray Conner said last month.
For the moment, the US government is sticking to its old hardline policy which has led to a number of aviation mishaps and the deaths of hundreds of Iranians.
In May, US Treasury Department imposed sanctions on two aviation companies for selling second-hand Airbus aircraft to Irans second carrier, Mahan Air.
By Press TV
