X-15 PILOT QUESTIONNAIRE

 
  FLIGHT 2-37-64 Pilot - John B. McKay

I. PRELAUNCH AND LAUNCH PHASE

A. Evaluate briefly flight performance of the following items during the prelaunch period and/or the launch maneuver.
  1. Pressure suit operation - was excellent.

2. X-15 radios - were good.

3. APUs - were excellent.

4. Damper System - was excellent.

5. Inertial Platform System - Before launch it appeared to be working well. The launch panel operator stated his system in the B-52 was going in and out of memory, and he did have some doubts about it.

6. Flow Direction Sensor - After we got to hydraulics it appeared to be working very well.

7. Launch transients (q, f, y) - none to speak of. "You got some b on launch. This is almost 6 degrees." Six degrees, I didn't recognize that b. Of course you're trying to get started, pullup, but after going and shooting out on the flight path the b was essentially zero.

8. Launch space positioning - was excellent, just as planned. There was no real problem, I believe, on making Hidden Hills.

9. Engine start - was normal.

10. Unforeseen incidents - none at launch.

 II. BOOST PHASE A. Evaluate flight performance in the following areas during the "power on" portion of the flight.
  1. Engine operation - was excellent.

2. Roll and/or yaw out-of-trim indication - Well, not any particular out-of-trim situation here but a deadband in the control system. There was a 5 to 8 degree roll oscillation that we were getting with about a one second period. It is very aggravating. "Say 5° both sides of zero?" Right. It could be the acceleration of this thing that makes you think you have an extreme bank angle because I couldn't see the horizon without sticking my head out. When you're trying to fly angle of attack and a certain profile and then you have to contend with roll, it does take away from your concentration. I didn't notice any tendency one way or the other.

3. Pitch and roll controllability - was very good during the rotation. I would rate the ability to use pitch and roll to get a profile about 2 1/2 across the board (q 2.5 , f 2.5 , y 2.5 ).

4. Altitude profile versus simulator - I think we went just a little bit high. However, the cues that we were using, the main one that I think threw me off a little bit was the 2000 feet a second at 50,000. This was almost right on. Well then, when you begin to think about it, that's good for a lot of things. Unless you have a high thrust you're not going to pick it up right at that time. The push over at 3000 feet a second came about 64 seconds which was about right for the simulator. We got anywhere from 65 to 63 on the simulator and it's still coming out on the profile. So, I would say that the altitude profile versus the simulator was very easy to match as far as the controllability of the airplane. However, a little - 300 or 250 pounds more thrust - maybe put us just a little high.

5. Unforeseen incidents - none. "Comment on negative a." I got a call from NASA-l that I was going just a little high so I purposely went negative for just a few seconds to try to control this. "Did it feel bad? You got some oscillation." Not very bad, in fact, the oscillation that we were picking up was hardly noticeable.

 III. GLIDE PHASE A. Evaluate flight performance in the following areas during the "power off" portion of the flight.
  1. Burnout transients - There were no burnout transients that I could detect, although in Maj. Rushworth's last flight they did come out with some calculations showing that he had burnout transients. It might be well to check on this but I couldn't feel any. "You had a very smooth shutdown." You know why? At about 4000 feet a second I grabbed the throttle to see whether I could reach it, and all I could do was get my hand on the side of it, just my finger. So I reached in the little detent, pulled it back about a third of the way going through about 4500 fps. I want to be sure and get a handle on that thing.

2. Roll and/or yaw out-of-trim indication - Only when I cut the dampers off in roll did I notice any, but with the dampers on and after drop I noticed no out-of-trim condition. "How about the roll you mentioned?" This is just tied into the boost phase. We may have had this afterwards but whatever I was doing with the airplane, trying to maneuver around into a 2g turn, get the damper off, and go into these series of pulses, I didn't recognize any of this sort of thing.
 
 

3. Controllability following each maneuver -
 

a. Left Bank

Velocity 4400 to 4000 fps. The controllability here was very good, I would rate it 2 1/2 across the board (q 2.5 , f 2.5 , y 2.5 ).

b. As far as these different pulses, I wasn't trying to control the airplane in these pulses. The stick pulse was a stick free situation where I took my hand off and wanted to just roll through it. "This is after you do your maneuver and when you decide you've watched it enough to stop it." Well, I didn't try to stop it. I turned the damper on and it stopped right there. "Can you rate the airplane response?" About 2. "This is pitch?" Right. I'd say the same thing for stopping the roll divergence too. I stopped that by cutting the roll damper back on it and it stopped it immediately. "This actually wasn't a pulse though, this was the airplane." That was the airplane itself. I didn't actually get any rudder pulses, I couldn't get the airplane stabilized enough dampers off to do this. You know, you're up to around 4000 feet a second and you have nothing to do back to the field except the pulses. I wanted to really look into this sort of thing. I tried it again, she diverged off and I was thinking about it again and all of a sudden I got the call to get going on the Star Tracker. "Did you notice the same thing in the simulator?" You mean the roll or the pitch? "The roll." I would say it was somewhat similar. It's pretty hard to tell when you're just looking at one mode instead of trying to fly the airplane dampers off completely. It's enough to make you sit up and take notice about it. The rate the airplane was diverging in roll, I'm sure would have carried it right over on its back in about a second. As far as recovery of the pitch pulse I'd rate that as a 2. Rudder pulse - I didn't get a rudder pulse. The only thing I can cover as far as the rudder pulses here is that the airplane recovered very well when we threw the roll damper and the yaw damper back on but it was the roll damper that was doing the controlling, not the yaw. I remember now when I turned the roll damper back on and straightened the airplane up, it was a few seconds before I cut the yaw damper back on and it didn't seem to make any difference on the controllability of the airplane with the yaw damper on or the yaw damper off. Even with the yaw damper on in the simulator if you roll the airplane you're going to get some b.

c. Additional maneuvers - (Star Tracker attitude acquisition) I would rate this about 2 across the board (q 2 , f 2 , y 2 ). It was a very nice airplane to fly with the dampers on.
 

 4. Glide energy management versus simulation That appeared to be similar. It's very hard to tell when you're looking up at a closed-loop TV system.

5. Controllability during the approach and landing - 2 across the board (q 2 , f 2 , y 2 ).

6. Unforeseen incidents - none. I was reading 40,000 on the inertial altimeter which was probably about 10,000 feet high coming down into down wind, so I would say probably about 3O,OOO, 300 knots indicated and going transonic we got the buffet again.
 

 B. Describe and rate the most adverse overall piloting task experienced on this flight.

Well, I can't really think of any bad piloting task. It was just a matter of trying to get the nose up to keep from going so low. "How about the trim required to hold angle of attack during rotation?" It appeared to be a little bit more than the other airplanes. I never did get to stop on the trim, but I really hauled into it. It would be interesting to see just what we did have. When I got to 12° I stopped on the trim, and it took very little pressure to hold 12°. Of course, it slacked down to 10°, then came down to 8°. I would say that the most adverse piloting task was, again, on the pushover, when you went from a nice stable climbout to a O g maneuver and trying to hold O g and O a. We kept cross-checking between that and your altitude and your check points. The airplane responded very well to any inputs. I'm not saying this was a controllability problem, it was just an adverse piloting task, there's a difference. As far as airplane controllability I'd say 2 1/2 across the board (q 2.5 , f 2.5 , y 2.5 ). Once you made up your mind you wanted to do something to make that airplane do it, it'd do it. In comparison to the way the airplane flew before it was modified, it takes a lot more stick motion to make the different pitching moments change now than it did before. This was brought up by John Manke in the simulator and it's very apparent. In fact, if anything, I'd say it's more apparent in the airplane than it is in the simulator. "The difference in piloting tasks between this and the old number 2 airplane." If you want to get that nose up or push it over, you've got to really horse in on that side arm control. "Only on the longitudinal?" Right, the yaw and roll modes apparently seem to be the same.