A Swedish Gripen fighter with a GKN RM12 engine powered by 100% renewable biofuel successfully completed the first biofuel demonstration flight in a single-engine installation on 28th March 2017. According to GKN Aerospace, the RM12 engine showed excellent performance both in-flight and on the ground. The specific biofuel used (CHCJ-5) is fully interchangeable with normal jet fuel and therefore no engine changes or modifications were needed.

GKN Aerospace, Saab and FMV will use this flight to demonstrate the potential of biofuel for military aerospace, as part of efforts to reduce the environmental impact of aviation. GKN aerospace is also strongly involved in the Clean Sky programme which is the largest European research programme developing innovative, cutting-edge technology aimed at reducing CO₂, gas emissions and noise levels produced by aircraft.

GKN is Type Certificate holder for the GE F404-based RM12 engine, following its acquisition of Volvo Aero in 2012. The company reviewed fuel specifications and material compatibility for all fuel wetted components in the engine in order to ensure safe engine operation and flight safety. Initial ground tests were performed with an instrumented engine where engine critical data was monitored.

Airworthiness was approved for the engine after satisfactory evaluation of measured engine data. Flight tests were then performed where engine performance/operability data again was monitored in real-time through a telemetry link.