The Royal Air Force of Oman currently has three C-130H Hercules in service, which were delivered between 1981 and 1983. Last year the air arm also took delivery of the first of three new-generation C-130J-30 aircraft from Lockheed Martin and two more remain on order. The 30-year-old C-130H fleet recently began to be put through an upgrade programme by Singapore-based ST Aerospace, at the centre of which is a Rockwell Collins Flight2 avionics system, providing pilots with greater situational awareness and communications capabilities. Turnaround time on the first aircraft was only seven months and it returned to service alongside the new C-130Js in February 2014.