A key safety feature of the aircraft's main gear box (MGB) is an emergency oil spraying sub-system present in the lubrication system; this is designed to exceed the JAR 29 Standard's requirements of a 30-minute running time in the event of the loss of MGB oil pressure, and has demonstrated up to 50-minute running time. The engine also incorporates a "blade shedding" system to ensure engine integrity during an overspeed instance. Energy absorbent self-sealing fuel tanks are contained in the aircraft's sponsons, along with other equipment such as downward-facing illumination and navigation lighting fixtures. The transmission can accommodate more power than the maximum output of the engines; however two aircraft were lost in 2012 due to the cracking of the bevel gear shaft, a gearbox component. In response, the design of the transmission was modified in 2013, and the onboard health and usage monitoring system (HUMS) was upgraded to provide real-time monitoring of the bevel gear shaft against the threat of crack formation.