Royal Australian Air Force Airmen from the 33 Squadron deliver fuel from a KC-30A Multi Role Tanker Transport (MRTT) to a U.S. Air Force C-17 Globemaster III and deliver U.S. Army Soldiers to Fort Bragg, N.C. in support of Exercise Mobility Guardian 2017. The Airbus A330 Multi Role Tanker Transport (MRTT) is an aerial refuelling tanker aircraft based on the civilian Airbus A330. The A330 MRTT has been ordered by the Royal Australian Air Force (RAAF), Royal Air Force (RAF), United Arab Emirates Air Force, Royal Saudi Air Force and Republic of Singapore Air Force. The EADS/Northrop Grumman KC-45 was a version of the A330 MRTT proposed for the United States Air Force. Designated as KC-30A, the Royal Australian Air Force (RAAF) A330 MRTTs are equipped with both an Aerial Refuelling Boom System (ARBS) and two Cobham 905E under-wing refuelling pods. The aircraft are powered by two General Electric CF6-80E engines. Australia initially arranged to procure four aircraft with an option to obtain a fifth; this option for a fifth aircraft was exercised to allow for two simultaneous deployments of two aircraft, the fifth being for contingency coverage. Australian KC-30A are operated by No. 33 Squadron RAAF based at RAAF Base Amberley.