October 26, 1965
MEMORANDUM for Chief, Research Division X-15 Project Office
Subject: Preliminary evaluation of X-15 flight 1-58-97
Flight 1-58-97 was flown on September 9, 1965, by Lt. Col. R. Rushworth. The launch lake was Delamar and the launch heading was 214° magnetic.
The flight had two
research purposes, they were:
1. Singer Infrared Scanner2. Ablative Test
Flight Summary
The profile was good up to 60,000 feet. At this point the pilot pushed over to zero a. As he performed this maneuver, he noted that a was not functioning. A cross-check of the g-meter verified that a was stuck at 5 degrees. During this maneuver, the pilot pushed over to about -0.3 g's and remained slightly negative until shutdown.
A maximum velocity of 5,183 ft/sec. and a maximum altitude 99,600 feet were attained during the flight. The energy management did not match the simulation because of the low profile.
The pilot reported a steady state sideslip during the glide phase. As a check on beta the pilot switched to computed beta. The same sideslip indication was noted. Postflight examination of the aircraft revealed a 1/8 to 1/4 degree offset in rudder deflection following a left rudder command.
A review of the internal recordings indicated the port SAS servo was not functioning properly. A system evaluation of the servo revealed an intermittent oscillation at zero rate. A new port servo amplifier was installed and a recheck of the system indicates SAS is functioning normally.
Mission Objectives
This flight was planned for the purpose of continuing the USAF-RDT IR Scanner experiment, and as an ablative test.
A review of the
data obtained with the scanner disclosed this data to be the best obtained
to date.
Conclusions
All objectives for this flight were accomplished. The data obtained from the IR Scanner were exceptionally good.
The problem with
sideslip reported by the pilot during the glide phase was caused
by a rudder offset. This condition has been corrected.
Paul L. Chenoweth
Aerospace Engineer