Air Platforms

Singapore air force concludes KC-135R operations

11 November 2019

A RSAF KC-135R Stratotanker preparing for take-off during an overseas exercise. The service’s fleet of four Stratotankers has now been retired in favour of six Airbus A330 MRTTs. Source: IHS Markit/Kelvin Wong

The Republic of Singapore Air Force (RSAF) ceased operating its four Boeing KC-135R Stratotanker aircraft in June, with the new A330 Multi-Role Tanker Transport (MRTT) taking over its roles in providing air-to-air refuelling (AAR), airlift support, and aeromedical evacuation for the Singapore Armed Forces (SAF), service officials revealed during a media briefing held at 112 Squadron on 11 November.

Singapore acquired four ex-United States Air Force (USAF) KC-135A Stratotanker aircraft in 1996 - which are understood to have been worth approximately USD280 million at the time - to complement its existing air-refuelling tanker fleet of four Lockheed Martin KC-130Bs and one KC-130H Hercules platform.

The Stratotankers were upgraded to the KC-135R configuration by Boeing following reactivation from storage at Davis-Monthan Air Force Base's Aerospace Maintenance and Regeneration Group and delivered to the RSAF at its newly stood up Peace Guardian training detachment at the USAF's McConnell Air Force Base in Kansas from 1999. The first KC-135R aircraft returned to Singapore in September 2000, with the fleet - operated by 112 Squadron based at Changi Air Base (West) - attaining full operational capability (FOC) in August 2002.

Major updates incorporated into the KC-135R included CFM International CFM56 (F108) turbofan engines that were up to 25% more efficient at cruising speeds and offered more reliability than the original J57 turbojets.

The type also benefited from a new glass cockpit and avionics suite under the USAF's Pacer CRAG (Compass, Radar, and GPS) programme, which had been designed to reduce workload through automation of many of the cockpit functions and coupled with modern human factor engineering techniques. This enabled the aircraft to be operated without a dedicated navigator and reducing the cockpit crew complement to two.

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