Test pilot Graham Tomlinson guides the supersonic F-35B Lightning II stealth fighter in a 40-knot (46 mph) flight above Naval Air Station Patuxent River, Md., then descends for a 75-knot (86 mph) slow landing. The flight on Wednesday, March 10, was one of the last missions before the aircraft's first vertical landing. The F-35B features a shaft-driven lift fan propulsion system that produces more than 41,000 pounds of vertical thrust, enabling airspeeds from zero to Mach 1.6. F-35B customers include the U.S. Marine Corps, the United Kingdom's Royal Air Force and Royal Navy, and the Italian Air Force and Navy.