B. An improvement in the cooling of the inertial platform computer was noted during this flight as indicated by the heat exchanger exhaust temperature. The computer installed for this flight, S/N 1, is unique in that the A.C. power consumption by the computer circuitry and the heat generation are reduced. This is the first installation of computer S/N 1 in X-15-3. Reference flight report 3-24-41.

B. Engine S/N 108 was replaced with engine S/N 109.

C. A modified flap teleflex gearbox was installed incorporating bronze bearings in place of the carbon bearings previously used.

B. The Block spectrometer E8-B S/N 020 was installed and operational for this flight.

C. Calibration of the boundary layer noise transducer was completed and acquisition of quantitative data is expected.

D. An inertial system stabilizer was installed incorporating modified amplifiers to reduce low pressure electrical arcing tendencies.

B. A ground run with engine S/N 108 was attempted on 12/6/63, however, the main propellant valve transfer micro switch failed, causing shut down during two attempts. Engine S/N 109 was installed, and an acceptable ground run was accomplished. Weak spark intensity was noted on the #1 igniter plug following the run.

C. Evaluation of the engine run data indicated excessive idle thrust, and a second adjustment of the throttle synchro was made to obtain the required 28,200 to 30,000 pounds thrust at idle.

D. The flight was rescheduled for January 14, 1964 because of X-15-1 flight activities and the year end holiday conflicts. Maintenance, modification to instrumentation, and preflights were accomplished during the down time.

E. A satisfactory ground run with engine S/N 109 was accomplished on January 9, 1964 with an idle thrust of 29,700 pounds. Cracks which were beyond limits were noted in the engine injector and expansion "canoe" at the 10:30 location, however, RMD recommended continued operation.

F. Cockpit leakage was checked at 78.5 CFM prior to flight.

G. A reevaluation was made of the one year extension in serviceable life for the ejection seat stabilization boom initiator charge. The two boom charges on the X-15-2 ejection seat were successfully fired to qualify the remaining four units for the extended four year total serviceable life. The one year extension ends in July 1964.

H. Intermittent operation of the Nos. 2 and 3 igniter plugs was obtained during the preflight engine functionals on January 13, 1964. The engine was removed to replace the igniter plugs and harnesses. A satisfactory ground run was accomplished on January 14, 1964. The engine injector cracks approved prior to the ground run were unchanged.

I. The inertial system stabilizer was removed to verify the integrity of the case seal and to inspect for evidence of arcing of the electrical components. During the requalification check after aircraft installation, a malfunction of the computer cross-range required replacement. Computer S/N 1 was installed, reference item III-A.

B. The engine shutdown occurred prematurely at 90 seconds with the engine at idle power setting. Decay of LOX manifold pressure preceded the shutdown. Evaluation of data and other checks will be made to define the causes.

C. Seizing of the speed brake controls during flight was reported by the pilot. The condition was corrected when the speed brakes were used during landing approach. Inadequate hot compensation in the cable tension regulators is considered the cause of the handle actuation force buildup.

D. A serious hydraulic leak developed in the yaw No. 2 system pressure flex hose. Hydraulic system operation was normal through the APU shutdown.

E. Noise generated by the cockpit VDR 4 camera affects the heart sound signal in the pilots blood pressure recording system.

F. Wear on the CERMET coated skids was limited to localized loss of the Cu-Cr overlay. Coating bond was good. Further testing is necessary to complete the evaluation.