Flight No. 2-25-45
Pilot: Jack McKay
After I got an engine light, I remembered what NASA 1 had previously said about being 1° off on a, and when I got up to about 12°a, all of a sudden it shot down to about 6° and kept oscillating during the flight. The a needle indicated a little low on profile to begin with, and I intentionally went past my programmed climbout angle of about 20° and pushed over at the 40-second point. I can recall Joe's remarks on his last flight that he was about 10,000 feet low on altitude. In connection with this, I believe the pressure altitude is really no good on these type of flights. I was cross checking between pressure altitude and NASA l's callouts on the ground which actually are the most helpful. When I went past about 52,000 feet NASA 1 called out about 65,000 feet.
I think after about the third call I reduced to minimum thrust I was holding it off intentionally. I finally got up to about 1450 q before I reduced thrust. The airplane seemed to stabilize pretty well around this area, but as I began to climb a little in altitude, the q appeared to be going the wrong way. The speed began to increase so I extended dive brakes a little and then increased them a little more, but I never did see over 1550 q.
All this time I could hear what sounded like somebody in the back end of the airplane pounding with a sledgehammer. I saw the same sort of smoke coming up in the cockpit as I did last time, but I saw about three or four times as much. In fact, one time I was looking at my airspeed indicator and I cannot remember what it said because the smoke was actually obscuring the meter.
About this time, I went into the stability and control set of pull-ups and pushovers and I definitely think, in fact I know, that our angle of attack is off. I'd pull up to 5°a and the needle would pitch down to 2° as I held the same pressure on the stick. I'd pull up to 10°a and do a roll and it appeared to hold 10°. I'd do a right roll after doing a left roll, and it would jump down to about 6°a which was definitely not what the simulator indicated. In fact, it seemed that these rolls at 10°a are somewhat harder to hold in angle of attack, in the airplane than in the simulator. I attributed this to the angle-of-attack indicator. I definitely think the angle of attack was off.
Just after drop I noticed the same 2° left yaw I had on the last flight. I put in a little right rudder to counteract it and, after I put in the healthy inputs, it started coming back. I let loose of the rudder and it went back to its original 2° off.
On the first roll, a looked pretty good, but when I went to the right roll the thing seemed to take a transient. I was flying with the sidearm stick all the way and I don't believe I put in a forward input. I believe it was the angle-of-attack indicator. Practicing these things beforehand on the simulator to get approximate data helps quite a bit, but I believe that the angle-of-attack indication was extremely off during this flight.
I intentionally went past my 20°q point, and at just about t = 38 seconds, I went back through 20°q and pushed over to zero g. It appeared to me at the time that it took a lot longer to pushover. NASA 1 was giving me all these callouts and I could tell that I was going over profile. At one time I went to about a negative 0.25g.
I was intentionally holding off on minimum thrust and I looked down at my inertial velocity indicator and I was going past 4400 fps. I was primarily flying on q and when I got to about 4500 fps I reduced thrust. Thrust control seemed to be normal for what we want on this type of low Mach number flight, and with a little addition of dive brakes you are able to hold the acceleration down.
There is another
thing I would like to bring up. I didn't go through the SAS check before
drop and I didn't get any SAS tripout during the flight. I don't know if
this was any kind of a consequence, but I personally took it upon myself
not to go through any SAS gain changes before flight. It puts a burden
on you, sitting there strapped in, and having to reach down for those switches.
I decided not to go through the switch change. I checked my SAS 8-6-8 before
drop and I did not have one single tripout.
JM:dmo
Typed: 9-13-62