An international aviation information organization says the plane which crashed into Lake Yirol on Sunday, killing 20 passengers, was first flown in 1984.

The 19 seat passenger caravan had 22 people and two crew members on board when it plunged into the river.

Among the dead were two children and the Bishop of the ECS Yirol Diocese, Simon Adut.

Three passengers: a 5-year-old girl, a 40-year-old man and an Italian doctor survived the crash and were flown back to Juba.

The South Sudan Civil Aviation Authority is yet to publicize the cause of the crash.

The Czech-built twin turbo-prop was being operated by Ukrainian carrier Slaver Kompani on behalf of South Sudan-based South West Aviation.

According to the Civil Aviation Authority Act of 2012, any plane that flies within the airspace of South Sudan has to be airworthy.

“The aircraft involved in the accident was originally delivered to Aeroflot in 1984,” said Flight Global.

” Flight Fleets Analyzer shows the aircraft was with various operators up until 2006, when it was withdrawn and stored at Rivne in Ukraine.”

This meant it re-entered into service after more than a decade in storage.

Slaver Kompani acquired the Let 410-UVP in April this year and has been operating it on wet-lease for South West Aviation since May.

According to aviation experts, on average, an aircraft is operable for about 30 years before it has to be retired.

This, however, depends on how it can endure pressurization cycles that with time cause metal fatigue on planes.

When planes are retired or kept in storage, they are either sold to movie industries or the spare parts are removed and sold.

Via Eye Radio