X-15 OPERATIONS FLIGHT REPORT

FLIGHT NO: 3-52-78 DATE OF REPORT: 8-9-66

PILOT: William H. Dana DATE OF FLIGHT: 7-18-66

CARRIER AIRCRAFT: B-52 #003 LAUNCH LAKE: Hidden Hills

ENGINE NO: S/N 111 APU #1 14AN APU #2 23AN

PURPOSE OF FLIGHT: 1. Pilot Checkout

2. MH Inertial System Checkout
3. Cockpit Display Evaluation
4. Horizontal Tail Loads
5. Stick Kicker Checkout

I. Discussion of Previous Operations

A. This report is broken up into portions concerning effort prior to, during, and after the rewiring and inertial modification.

B. Servicing of NH3 for 3-A-77 was accomplished 5 hours 24 minutes prior to takeoff. The NH3 temperature went from -50°F to -35°F at igniter idle.

C. A great deal of effort was expended by the operations and instrumentation crews in rewiring and modifying the aircraft. Subsequent functional checks and debugging was a minimum. The crews are to be commended for a good job.

II. Events Prior to Major Aircraft Modification, Oct. 27 to Nov. 29, 1965 A. Discussion
1. A great deal of concern had been expressed over the natural frequencies of vibration of the pylon on B-52 #008. After flight 3-51-75 using B-52 #003, the data was removed and the aircraft mated to #008. Vibration tests were accomplished on October 29, 1965.

2. Per request of flight planning, engine alignment was checked and found to be within specification.

B. Aircraft Configuration Changes
1. Engine S/N 109 was replaced by S/N 106 for a bad metering valve.

2. The new -400 M.L.G. oleo's were installed.

C. Instrumentation Configuration Changes
1. The strain gages for tail loads were hooked up.
D. Preflight Events
1. An engine run was accomplished on November 5, 1965.

2. APU and BCS runs were accomplished on November 5, 1965.

3. Some Station 226 screws, double row around fuselage were tightened and some checked for deformation, no deformation was found.

4. The aircraft was weighed in a ready-to-mate condition on November 8, 1965.

5. The aircraft was mated to B-52 #003 on November 8, 1965.

6. Flight canceled on November 9 for weather just prior to pilot entry.

7. During purge on November 9, the #1 APU tank bladder was found to leak and the tank was changed. The NH3 auxiliary jettison valve leaked and was changed.

8. Flight was canceled on November 10 for a closed restricted area.

9. The rains came over the weekend of November 13 and 14, and flight was postponed because of a wet lakebed. On November 16, more rain came so the aircraft was demated to re-preflight. Due to more rain and worsening condition of lakebed during the period of November 16 thru 22, an investigation was conducted concerning starting the Honeywell modification and rewiring early. On November 29, the go ahead was obtained and the modification started.

III. Major Modification Events Summary A. During tear down for rewiring, cracks were found in the canted bulkhead clips on the LH side. The cracks were repaired, the inner skin replaced between about 4 and 8 o'clock positions between the canted bulkhead and forward elevator rails. Four stiffeners were added between the inner and outer skin in this area to better distribute loads to prevent future cracking.

B. The aircraft was completely rewired, operation and instrumentation wiring, except for T/C's.

C. The Honeywell inertial system was installed similar to X-15-1.

D. The Honeywell computer was installed for energy management presentation, although it will not be utilized for initial flights.

E. The Lear vertical instruments were installed in a NASA designed instrument panel. The panel was designed with all switches on the left.

F. The following landing gear modifications were accomplished:

1. The -400 shock struts were incorporated (actually done prior to modification period).

2. The third skid was installed, including beef-up at Station 200.

3. The increased strength MLG uplock hooks and roller brackets were installed.

4. The stick pusher was installed.

G. The beef-up in the engine compartment for the Ballute experiment was installed.

H. The wing tips were modified to accept the tip pods presently installed on X-15-1.

I. The cockpit regulator was relocated to the LH side of the elevator bay similar to X-15-1 (reference: Flight Report 1-63-104).

J. The sunshade was installed on the LH side of the canopy.

K. Additional strain gages were installed on both stabilizer torque boxes for the tail-loads experiment.

IV. Events During Preparation of Aircraft for Flight A. On April 18, 1966, the aircraft instrument panel was operated in the inertial laboratory from the inertial system.

B. On April 23, electrical power was applied to the aircraft. By April 30, all major aircraft electrical systems had been checked.

'C. A set of functionals was started on May 2 to check all aircraft systems.

D. Number 1 APU, S/N 13AN, and #2 APU, S/N 23AN, were installed on May 8. Engine S/N 111 was installed on May 20.

E. The inertial system was first operated on May 20.

F. An engine run was accomplished on June 6. APU runs were accomplished on June 6 with inertial, instrumentation, and MH-96 operating. Some peculiarities occurred in inertial which were checked later.

G. Number 1 APU, 13AN, lost the turbine shaft seal and was replaced by 14AN. A cooling orifice was found plugged which caused the overheat condition.

H. An APU run was made on June 10 with instrumentation, inertial, and MH-96 systems operating.

I. During engine functional S-24 failed requiring a control box change on June 14. On June 15, a diode was found shorted out across the prime solenoid which ruined the prime relay requiring a control box change.

J. The NH3 tank regulator failed open during servicing FOX source for the engine run on June 15. The regulator was changed and a good engine run made on June l6.

K. The aircraft was weighed on June 17.

L. The aircraft was mated to B-52 #003 on June 18. The computer failed during a post mate check and was changed.

M. During servicing on June 20, the radar beacon failed and was changed. The computer malfunctioned about 1 minute after power transfer resulting in aborted flight 3-A-76. The flight was continued thru igniter idle. The APU's were run after landing and successful power transfer accomplished. Due to the pilot being gone the rest of the week and the investigation of inertial system on ship 1, the aircraft was demated for re-preflighting. A close check of the flight data shows that the computer probably overheated causing the failure. The cooling system was modified to provide more air flow through the computer.

N. An APU run was made on July 11 with inertial, MH-96, and instrumentation operating.

O. The aircraft was mated to B-52 #003 on July 12.

P. On July 13, the cabin regulator was found to be closed after pilot entry. The regulator test Crocker valve was bypassed and normal operation obtained. Lox and pylon were topped off and Flight 3-A-77 accomplished. Flight was aborted for a gross computer light just prior to launch. The TM failed shortly afterwards. The gross light was found to come from an interference from the bugeye camera pulser, and the bugeyes were deleted for flight. The TM failure was found caused by an incorrectly sized blown fuse.

Q. Flight was not attempted on July 14 for above trouble shooting, and canceled on July 15 due to support problems.

V. Flight Events A. The pilots O2 regulator started leaking over the weekend and was replaced on the morning of flight.

B. Flight 3-52-78 was accomplished on July 18. The velocity indicator was erratic at engine shutdown. The third skid deployed satisfactorily. The rudder number 1 hydraulic system return line was found to be leaking after landing.

Approved By: Prepared by:

Perry V. Row Vincent N. Capasso

X-15 Senior Project Engineer X-15 Project Engineer