B. The left hand APU tank incorporating a Teflon bladder was replaced. The replacement tank contained a vicone bladder. A later inspection of the replaced tank indicated the upper edge of the bladder had slipped out of the top retaining flange.

C. The investigation following the landing of X-15-3 at Cuddeback revealed that improper upper drag link bolts were installed. NAS 1306-17 bolts were also installed in X-15-1 instead of 1306-17 W-SPL. Yield strength of the improper bolts is lowered from 180 K psi to 160 K psi minimum. The bolt deviation was accepted for one flight pending receipt of special bolts.

B. After flight l-A-76, the KS-25 filter was changed to improve data results.

C. The Sperry Inertial System performed satisfactorily during all ground checks and flight 1-A-76. Post mate checks prior to this flight indicated a malfunction, resulting in replacement of stabilizer and computer. Stabilizer S/N 1 and Computer S/N 6 were qualified for flight.

B. Preflight of the KS-25 revealed a buildup of emulsion on the film transport mechanisms, causing unsatisfactory operation. Partial disassembly and a thorough cleaning resulted in reliable, smooth operation. A hang up was also experienced due to a splice in the film roll where the leader was attached.

C. Unacceptable weather caused cancellations on 6/4/64, 6/5/64, 6/9/64 and 6/10/64.

D. Flight 1-A-76 was accomplished on 6/11/64 with M. O. Thompson as pilot. The SAS malfunctioned with an apparent system power failure. The extent of the SAS malfunction required demating for a complete investigation. X-15 communications were also considered unacceptable.

E. A post flight investigation of SAS revealed failure of the pitch and roll channel D.C. malfunction detector modules and blown fuses. Inspection of the aircraft wiring did not locate the cause, and satisfactory SAS operation was obtained with a replacement SAS Electronics Case. Shorts between the D.C. malfunction detector module wiring and case power circuits were later found to be the cause of module failure.

F. John McKay replaced Milton O. Thompson as pilot for the flight.

G. The aircraft flight functionals were reaccomplished and APU runs completed on 6/16/64. The #l APU metering valve leaked H2O2 internally and unit S/N 054G was replaced with S/N 542F. Metering valve seal failure is presently a chronic problem.

H. The aircraft was closed out for flight on 6/25/64, however, X-15-2 was in possession of B-52 #003. B-52 mating was accomplished on 6/29/64.

B. A complete loss of the inertial data system occurred at launch, and an alternate emergency flight plan was executed. The KS-25 system operated satisfactorily in the automatic V/H mode, however, only a fixed V/H ratio was available as determined by the launch altitude and velocity. No attempt was made to select manual IMC because of the difficult pilot task.

C. The decision was made on 7/1/64 to remove the KS-25 experiment and to initiate the installation of the X-20 Honeywell IFDS.