On aircraft gas turbine engines, the gearbox and lubrication & scavenge pump systems are usually at the bottom of the engine. Due to space constraints, the oil reservoir (or tank) is often higher than the pump and gearbox. When the pump is not running, oil from the tank can slowly drain through the pump and into the gearbox. This would cause the oil tank level to appear that additional oil needs to be added. By adding oil to top up the tank, the service technician would be overfilling the lubrication system. This leads to excess oil burning, environmental concerns, delays to troubleshoot, and other issues. This can all be avoided with the use of an anti-draindown valve, either on the oil line from tank to pump, or on the pump itself.Parker Aerospace anti-draindown valves effectively prevent lubricating oil from draining through the pump into the gearbox from the oil tank located higher than the gearbox and pump. APPLICATIONS: This technology is custom designed for use on lubrication systems on aircraft such as commercial, regional, military jets, and helicopters.FEATURES AND ATTRIBUTES: • Reduces false low oil readings that lead to overfill• Fireproof• Low weightOPTIONAL FEATURES: • Custom designed to be paired with the lubrication pump• Can mount on oil line or directly on the pump