The National Aeronautics and Space Administration's Johnson Space Center operates two WB-57F High Altitude Research Aircraft, both manufactured in the early 1950s. With the original wheels and tires no longer available, a challenging ops tempo, and with no nose wheel steering, no anti-skid, and difficulties with wet runways, it was necessary to upgrade the wheels and brakes. This required new main landing gear struts to accommodate the proposed new wheels. The wheels and anti-skid brakes from the F-15E were selected as the most capable and most compatible, and contracts with two vendors for the wheel and brake modifications and the new main landing gear struts were developed. A complete test program was required subsequent to the extensive modifications to certify the landing gear for operation. This involved a build-up program for high speed ground aborts, maximum performance heavy weight stopping, airborne retraction and extension verification, and wet runway anti-skid testing. Upcoming high priority international deployments created typical schedule pressures for the test team. A significant brake fire following a high speed ground abort test exacerbated the schedule issues. A thorough mishap investigation determined the root and proximate causes, repairs and re-designs were completed, the international deployment was partially accomplished, and the test plan was completed resulting in bringing to service a superb braking system for the WB-57F. This paper will present the test program details and results, the lessons learned from the mishap and test program, and the very unique method of operationally testing the anti-skid system involving flooding a commercial regional airport's non-grooved runway using commercial water tankers and fire trucks.
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