October 26, 1965

MEMORANDUM for Chief, Research Division X-15 Project Office

Subject: Preliminary evaluation of X-15 flight 1-61-101

A. General Information

Flight 1-61-101 was flown on October 14, 1965, by Capt. Joe Engle. The launch lake was Delamar and the launch heading was 215° magnetic.

A maximum velocity of 5,250 ft/sec, and a maximum altitude of 260,000 feet were attained during the flight.

At drop the yaw SAS channel malfunctioned. The pilot re-engaged the damper and it functioned normally during the boost and ballistic phase of the flight. At about 110,000 feet during the reentry the yaw damper again malfunctioned. At the completion of the reentry, the pilot again re-engaged the channel. No further problem was noted with the SAS system during the flight.

The profile was excellent for this flight. The altitude and velocity cross-checks were exactly as seen in the simulator. The radar plot matched the simulator profile through the boost phase.

The pilot workload was high during climbout because of the effort required to maintain instrument contact. The difficult pilot task, caused by glare from his suit, prevented the pilot from shutting down at the planned velocity.

B. Mission Objectives

This flight was planned for the purpose of continuing the phase I MIT horizon photometer experiment and the pace transducer experiment.

The data obtained from each of these experiments were excellent.

C. Handling Qualities

The BCS system functioned normally during the flight. The pilot rated the controllability with this system as:

q f y

1.5 1.5 2.0

The controllability during the initial reentry was rated as:

q f y

3.0 1.5 4.0

and during the terminal phase of the reentry as:

q f y

2.0 1.5 1.5

The most adverse control task encountered by the pilot during the flight was the initial reentry. The pilot ratings during this portion of the flight were as stated above.

D. Conclusions

All the objectives were accomplished for this flight. The data obtained were good and are being analyzed by the experimenter.

The SAS malfunction is being investigated. At present no answer can be given as to the cause of the failure.
 
 
 
 
 
 

Paul L. Chenoweth

Research Division

X-15 Project Engineer