NAVAIR ultimately developed the MH-53E Sea Dragon for the airborne mine countermeasures role, modifying the aircraft’s digital flight control system and increasing its fuel capacity and endurance. MH-53Es became operational in 1986.
The CH-53K King Stallion, which first flew in October 2015, will soon join NAVAIR’s inventory of test aircraft. With new engines, avionics, software, and structures, the King Stallion will be a huge helicopter but its footprint will actually be narrower than the CH-53E’s, though it will lift more than twice the load of the Super Stallion.
Not all test and development work leads to operational systems. Sometimes NAVAIR undertakes broader applied research. Such was the case with the Rockwell-Messerschmitt-Bölkow-Blohm X-31.
Two X-31s were built for the early 1990s Enhanced Fighter Maneuverability program, which was conceived to test fighter thrust vectoring technology. A cranked, canard delta-wing aircraft without horizontal tail surfaces, the X-31 relied on three paddles directing the exhaust to control pitch and yaw. In 1992-93, the X-31 achieved controlled flight at a 70-degree angle of attack and successfully executed a rapid minimum-radius, 180-degree turn using a post-stall maneuver.
Its success led to a second program in the late 1990s called VECTOR, a joint venture between NAVAIR, Germany’s defense procurement agency BWB, Boeing’s Phantom Works, and DASA. NAS Patuxent River was the flight test site from 2002 to 2003, where the X-31 flew extremely short takeoff and landing approaches first on a virtual runway at 5,000 feet in the sky to ensure that an inertial navigation/GPS system combo could accurately guide the aircraft with the centimeter accuracy.
VECTOR culminated with the first ever autonomous landing of a manned aircraft with high angle of attack (24 degrees) and short landing – a precursor for what the X-37B would achieve with no pilot over a decade later.
This article was first published in NAVAIR: 50 Years of Naval Air Systems Command, 1966-2016 magazine.