Flight No. 2-20-36
Major Robert White
The profile was going along well and I could hear Pete at NASA 2 for most of the powered part of the climb. The clock didn't run -- it started up for about a second and then quit. I let NASA 2 know this, he rogered back and, then he gave me a call, "Now going through 100,000 feet," and I was going through 100,000 just as he called it.
The longitudinal g seemed to build up a lot faster than I had experienced in the past. It also seemed to be much more than I had experienced in the past. I was a lot more impressed by the g pushing me back in the seat, from five or 10 seconds after the speed brakes went open -- from that time on.
During the climb NASA 2 started getting scratchy and foggy, but I was able to hear the call at 77, 78 seconds and about this time I got a little wandering in sideslip, and I instinctively reached for and wrapped my hand around the ballistic control stick and just as NASA 2 called 79 seconds, I reached for the throttle and burnout occurred at shutdown. So I imagine the time on shutdown compared with burning time should be fairly close. The shutdown didn't offer any problems as far as transient motions in the airplane are concerned, and about that time I went to reaction controls, as I passed through 140,000 on inertial height. I then trimmed the stabilizer setting to zero. The angle-of-attack bar and absolute a meter went down to -3 or -4° and throughout the rest of the ballistic portion of the flight. Here is where I had my main trouble. Reaction control in all axes is very good. We had planned the mission to be successful without reaction controls, but it was a comfort to have them, because as I started getting excursions in sideslip, pitch, and roll they were effective, and this should be evident when looking at the data. A few times I cranked in lateral control motion with the aerodynamic stick and then quickly convinced myself to stop that nonsense and get back over on the reaction controls, which did the job quite well, both in roll and in yaw when necessary. Pitch, however, gave me problems in that I was getting more response than I thought was available, and consequently the angle-of-attack excursions were fairly large. Going over the top, the angle-of-attack motions also resulted in a fair bit of attitude change. The airplane actually started pitching through a sizable attitude change as referenced by looking out at the horizon. I then concentrated on trying to steady the motions. I gave up the idea of trying to follow the given task of setting up a 5° angle of attack using the reaction controls, and just went ahead and tried to fly to all instruments to their null positions.
I was receiving all radio calls from the B-52, because by this time I couldn't hear Pete at NASA 2. I heard the B-52 say something like 200 and something thousand once and then I heard 220, and later I heard 180 at 180,000 feet.
I was using reaction controls fairly continuously at 180, 000 feet. At this time, I trimmed in the stabilizer for entry and as for the technique worked out on the simulator of trimming the stabilizer settings going through 180,000 feet and then very smartly with the reaction controls set up the angle of attack. Well, since I had been having a problem in pitch, it wasn't quite that neat. I chased the angle of attack around and finally ended up with about 10° for entry. As the cues of entry started coming up there were no control problems. I don't say there weren't any control problems with the reaction system for attitude, it is just that the response in pitch was very surprising. If we could sit at low q and play with it a while, I think I could become proficient in using the control.
There were no control problems for the entry. As the g came on I watched it build up to 4. I heard a call "coming below 70,000 feet," and then, when I was level, somewhere between 60,000 and 70.000 feet, I eased off on the g. I looked at the pressure instruments and saw between 1.6 and 1.8 on the Mach meter when somebody used the pick ax on the windshield, and it cracked.
From the peak of the trajectory I was able to see the lakebed. At level flight after entry, I was off to the right of the Rosamond area. It was just a matter of maneuvering around to the left to a downwind position for landing.
During the latter part of the flight, when I went to jettison I seemed to have some buffet on the airplane. I was flying at 5-6-7° a and I pulled it up to about 8° or 9° and the buffet would then increase a little bit, so I was satisfied that it was aerodynamic buffet. This was at about 40,000 feet.
The entire flight was flown on the side stick. Maneuvering around the landing pattern, I used speed brakes to dump off a little altitude and got a little lower than I wanted to be on final approach. I jettisoned the ventral and again I seemed low in order for the parachute to open. The usual trim change accompanied the flap deployment and here you have to talk yourself into correcting a little more than you did with the center stick because you notice the motion, but there was actually no problem in maintaining control. I passed the one-mile marker from the end of runway 18, pulled the gear handle at 240 knots and then just slipped it on down and landed. Touchdown was short of the spot, and felt fairly solid like on several other flights. I then came full aft on the stabilizer and opened up the speed brakes. The airplane held a straight flight path.
Question: Pertaining to pitch reaction control.
White: I was getting a fairly good oscillation in pitch so I thought well, let me see if I can take it up to 5 and then made a control input. I finally gave this up because, as I say again, with each control obligation the response I got was a lot more than I really wanted. Then it was just a matter of chasing after it to zero it up. I don't think there would be any problem as far as zeroing it out.
Question: Pertaining to the center stick.
White: I left the center stick aerodynamic control alone. I didn't use it at all and I don't think it would have done any good at the low q. It was very pleasing in both roll and yaw using reaction controls. There was just a bit more of a task in pitch.
Question: Did the pressure suit inflate?
White: Cabin pressure apparently was fine. I never did look at it because I never had any indication that there was pressure in the suit. In fact, I can't think of any one single thing as far as systems is concerned that gave any indication that they were not functioning properly. The inertial system looked good. I missed reading the altitude at the peak because this was in the area where I was chasing pitch motions around. I have never used reaction controls in this airplane before, so I was quite intent on a cross check right in this area.
Question: How was the side stick for landing?
White: I'd comment this way; it wasn't any difficult exercise and as far as I am concerned I would go out and land every time from now on out with the side control. I don't think it is more sensitive than the center stick. I think it is just a matter of doing it a few times to get used to the deflection you require, particularly in pitch, compared with what you are used to doing on center stick, but again the control system is so good and the response that you get out of the airplane at these speeds down to low altitude is just so perfect as far as what the pilot is looking for, that it is alright.
Question: Pertaining to inadvertent reaction control inputs.
White: It is interesting to note that when checking the reaction controls, while the X-15 is still mated, we seem to get an input in another axis other than the one we were working; well, I wasn't impressed with this one occurring in flight. I also wasn't impressed that there were any motions or any airplane upsets because of the engine shutdown.
One thing you're
very much impressed with during the entry is when the g comes on. Also,
the longitudinal g caused me to slide under the head bumper just a little
bit, so my head was actually down just a little bit because of -Ax.