X-15 OPERATIONS FLIGHT REPORT



FLIGHT NO: 2-40-72 DATE OF REPORT: July 26, 1965

PILOT: John B. McKay DATE OF FLIGHT: July 8, 1965

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

ENGINE: S/N 103 APU #1 7 AN APU #2 22AN

PURPOSE OF FLIGHT: (1) Star Tracker

(2) Altitude Buildup

I. Discussion of Previous Operations

A. "Loose" control by RAS in pitch and roll, was noted during the previous flight (2-39-70). Ground testing of the RAS system revealed no out-of-specification conditions. During this flight (2-40-72) oscillations were noted in pitch, although control in yaw and roll appeared good. Further detailed inspections of the RAS and BCS system rigging was performed, and nothing significant has been discovered. One factor contributing to this problem is the performance of the X-15 simulator which seems to display unrealistically tight control under the RAS/BCS systems. Further review of this problem area is underway.

B. High lock-up pressure of the Lox tank regulator during last flight resulted in replacement of that component prior to this flight.

 II. Configuration Changes A. The ASAS manual engage circuit was added to provide the pilot with the capability of engaging ASAS in the event of SAS power failure.

B. An ultra-violet spectrometer was installed on the Star Tracker camera platform for a U.V. frequency survey of the sky background.

C. An ablator test installation was made on the lower speed brakes, the ventral leading edge, and a section of the Lox tank skin, to test the feasibility of applying ablation material over a pressure sensitive tape (for easy stripping and clean-up after flight).

 III. Preflight Events A. System preflights were conducted with no major problems. No engine ground run was made. APU/BCS ground runs were completed on Monday, June 28, 1965. The catalyst bed in APU #l was replaced because of noticeable "chugging" of the APU while running.

B. A flight scheduled on the following Thursday, July l, 1965 was canceled after partial servicing, due to a burning odor originating in the equipment bay. The pilot's suit vent heater had inadvertently been switched on to the "high" position and had overheated since there was no gas flow through the heater at that time. Inspection of the heater required removal of the elevator. No significant damage was noted and the elevator was reinstalled late the same day.

C. A flight scheduled for Friday, July 2, 1965, ended in abort (2-A-71) when the stable platform failed to accept updating signals from the B-52. Inspection of the umbilical connector revealed a loose connection at the terminal appropriate to the observed malfunction. The terminal was secured and flight rescheduled for Wednesday, July 7, 1965.

D. The flight scheduled for Wednesday, was canceled just prior to B-52 takeoff when it became apparent that delays caused by repair of a B-52 fuel leak had put the target for the Star Tracker out of range of the X-15 roll limits currently in effect for the Star Tracker maneuver (40°).

 IV. Flight Events A. Flight 2-40-72 was completed on Thursday, July 8, 1965. Preflight servicing was uneventful. A ground jettison check was made. The pilot reported pitch oscillations during BCS/RAS operation (see item I A). Other than the above, operation of X-15 systems throughout the flight was good.
 
 
 
  Approve By: Prepared by:

Perry V. Row William P. Albrecht

X-15 Senior Project Engineer X-15 Project Engineer