Exploring the Unknown: Selected Documents in ... - The Black Vault

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First Steps into Space: Projects Mercury and Gemini
trainer would do at a -.1 (-.1 damping coefficient set into the trailer computer)
reentry. From this I decided that the spacecraft was in a good reentry attitude and
I selected Aux Damp.
I watched the rate indicator and the window during this period because I
was beginning to see the reentry glow. I was beginning to see a few flaming pieces
falling off the spacecraft, although the window did not light up as John Glenn
reported. It was just a noticeable increase in illumination. I did not see a fiery glow
prior to peak g as John Glenn did.
I noticed one thing during the heat pulse that I had not expected. I was
looking for the orange glow. I also saw a long rectangular strap of some kind
going off in the distance. It was at this time that I noticed a light green glow
that seemed to be coming from the cylindrical section of the spacecraft. It made
me feel that the trim angle was not right, and that some of the surface of the
recovery compartment might be ablating. I think it must have been the berylium
[sic] vaporizing. The fact that the rates were oscillating evenly strengthened my
conviction that the reentry was at a good trim angle. The green glow was really
brighter than the orange glow around the window. [3-5]
I heard Cape Cap Com up to the blackout. He told me that black-out was
expected momentarily. I listened at first for his command transmission, but it did
not get through. So I just talked the rest of the way down.
Acceleration peaked at about 6.7g. At this time, oscillations in rate were
nearly imperceptible. Aux Damp was doing very, very well. The period of peak g
was much longer than I had expected. I noticed that I had to breathe a little more
forcefully in order to say normal sentences.
The accelerometer read 2.5 to 3g when the spacecraft passed through a
hundred thousand feet. At around 80 or 70 thousand feet, we may have run out
of automatic fuel. I do not remember looking at the fuel gage but the rates began
to oscillate pretty badly, although the rate needles were still on scale.
I put in a roll rate earlier and after we got down around 70 or 80 thousand
feet, I took the roll rate out. So I did have fuel at that point. I took the roll rate out
at a point where the oscillations carried the sun back and forth across the window.
My best indication of the amplitude of the oscillation was to watch the sun cross
the window, and try to determine the angle through which the spacecraft was
oscillating. I remember calling off about 40 or 50 degrees. This was around 60,000
feet. At about 50,000 feet, the amplitude of the oscillations increased. I could
feel the deceleration as we would go to one side in yaw or pitch. I would feel the
spacecraft sort of stop, and then the rate would build up in the other direction.
I felt that I had a pretty good indication of the variation in attitude from this
change in acceleration. I switched the drogue fuse switch on at about 45 thousand
feet. At about 40 thousand feet, I began to feel that the spacecraft oscillations
were going past 90 degrees. I would feel a deceleration as the spacecraft would go
past the vertical. I knew from the amplitudes that I had previously extrapolated,
that the spacecraft attitude had reached at least 90 degrees. Then the spacecraft
would apparently slip past 90 degrees. I am convinced that the attitudes were