X-15 OPERATIONS FLIGHT REPORT

FLIGHT NO: 3-29-48 DATE OF REPORT: May 28, 1964

PILOT: Milt Thompson DATE OF FLIGHT: May 21, 1964

CARRIER AIRCRAFT: B-52 #003 LAUNCH LAKE: Silver

PURPOSE OF FLIGHT: Heat Transfer and Skin Friction Experiments

I. Discussion of Previous Operations

A. None II. Aircraft Configuration Changes (all made after 3-2-45) A. APU 26AN replaced with 14AN because of a leaking hydraulic pump.

B. NH3 tank regulator did not function properly during propellant functional and was replaced.

 III. Instrumentation Configuration Changes None IV. Preflight Events A. Based on the successful ground run of April 30, 1964, and flight on May 12, 1964, no engine run was made prior to this flight.

B. Cabin leakage was tested immediately after flight 3-28-47 and no change was found.

 V. Flight Events A. The YLR-99 engine malfunctioned at throttle back (42 seconds) and would not restart, necessitating an emergency landing at Cuddeback. The Engine malfunction was found to be caused by a pressure spike in the 2nd stage chamber pressure sensing line, a problem which has been present for several years. This engine has not shown a tendency to generate spikes since installation in X-15-3 (3 flights and 4 ground runs accomplished since installation). The intensity of the spike was sufficient in this case to deform the switch mechanically, holding the contacts closed and thus preventing engine restart.

B. The landing at Cuddeback resulted in higher than normal drag loads on the skids due to the softer lakebed surface at Cuddeback. Toward the end of slideout, the aircraft crossed the road at the end of the runway. The road was made by simply scraping the lakebed surface with a grader and allowing the dirt to pile on each side to a height of about 6 inches. This obstacle severely jolted the aircraft and landing gear structure. A detailed inspection of the gear and attach points will be necessary.

C. The inertial system operated properly during the flight and post flight checks. The computer was then removed for use in X-15-2.
 

 Approved By: Prepared by:

Perry V. Row Vincent N. Capasso

X-15 Senior Project Engineer X-15 Project Engineer