Flight 3-27-44 was flown by John B. McKay on March 13, 1964, for the purpose of obtaining heat transfer and skin friction data with the sharp upper vertical, boundary layer noise experimentation, and pilot checkout.

The launch configuration for this flight was MH-96 adaptive, R.C. off, heading vernier to "standby," and ventral off. The launch was made in the vicinity of Hidden Hills on a magnetic heading of 210.6 degrees at an altitude and velocity of approximately 46,300 feet and 843 feet per second, respectively. The maximum altitude, velocity, and dynamic pressure was 76,000 feet, 4956 feet per second, and 1387 psf, respectively.

Heat transfer and skin friction data were obtained during the powered portion, however, usability of this data is questionable as velocity attained was higher than desired. Evaluation of other flight parameters will determine the degree to which this data can be used. Boundary layer noise was not obtained as the tape recorder was not turned on. The cockpit camera operated intermittently during the flight, providing film for the powered portion through M » 2 and from the M » 2 to M » 1 portion of the flight. Insufficient flight time prevented the pilot familiarization portion from being completed as planned. Time was available for the pilot to engage the roll hold (6.2 seconds) angle of attack hold (3 seconds), and to complete a right roll (fmax » 55°, ^·y » 20.7°) and a left roll (fmax » -30.4°) with the dampers adaptive. Insufficient time remained to switch the dampers to fixed gain.

The pilot intermittently engaged and disengaged the control stick steering (CSS) function of the MH-96 flight control system during the flight. Launch and rotation were accomplished with this function engaged. During rotation the angle of attack increased to approximately 22 degrees. The pilot was aware of buffet during the subsonic portion and attributed the high angle of attack to the ease with which rotation is accomplished using the MH-96 system. Pilot ratings during the heat run were:

q 2.5 , f 2.5 , y 2.5 .

The pilot indicated that he found dynamic pressure easier to control with the MH-96 system. During the minimum thrust portion of the heat run, the pilot was aware of banging of the aircraft. Post-flight examination of internal recordings indicate transients occurred in the servos following pilot disengage of the CSS mode. Investigation disclosed a broken shield wire in the MH-96 elevator wiring.

The pilot indicated that approach is much simpler with the MH-96 system. He was also aware that the aircraft seemed harder to land although small corrections were more easily made during the touchdown phase. The total flight duration was 449.0 seconds (7.48 minutes).
 
 

James R. Welsh

Aerospace Engineer