GECAS-owned rotorcraft lessor Milestone Aviation and Leonardo Helicopters have disclosed a deal to supply a total of 21 AW139 intermediate twins to Aramco Overseas, a subsidiary of Saudi Arabian oil company Aramco.

The contract, the value of which has not been revealed, is for 17 firm orders, plus four options. Deliveries will run for three years, starting later in 2018.

Aramco will predominantly use the AW139s for offshore oil and gas operations, but a number will also be configured for search and rescue missions.

The Saudi company has operated a fleet of 14 AW139s since 2008, alongside seven AW109 light-twins, which it acquired in 2006.

The new helicopters are to replace older helicopters in the fleet, which include a number of legacy Bell types, Flight Fleets Analyzer shows.