The fourth P-3 Orion to receive the Mid-Life Upgrade, or MLU, kit modifications was redelivered to US Customs and Border Protection on 20 January 2012, two months ahead of schedule. The MLU installation and scheduled phased depot maintenance were accomplished in only eleven months at the Lockheed Martin facility in Greenville, South Carolina. The MLU kit replaces all fatigue life-limiting structures with enhanced-design components and incorporates a new metal alloy that is five times more corrosion resistant than the original material. The MLU kit will extend the service life of the P-3 fleet up to 15,000 hours and add more than twenty years of operational use. Once the MLU kit is installed, any current flight restrictions are removed.
