By M. SCOTT CARPENTER, Astronaut NASA Manned Spacecraft Center


[69] Summary


An account of the major events and personal observations of the MA-7 flight is reviewed by the pilot. Prior to and during powered flight, launch-vehicle noise and vibration were less than expected. As in the MA-6 mission, the astronaut quickly adapted to weightless flight and remarked that it was more comfortable and provided greater mobility than under normal gravity. Astronaut Carpenter also observed the space particles and the bright horizon band, previously reported by Astronaut John H. Glenn, Jr., and secured new information on both phenomena. The final phases of the flight, including retrosequence, reentry, landing and egress, are covered in detail.




The previous papers in this report have e considered the engineering and operational aspects of the MA-7 mission, including a scientific analysis of some of my flight observations. In this presentation, I shall attempt to give a narrative account of my impressions during the flight.

A period of more than 2 months, most of which was spent at Cape Canaveral, was consumed in preparing me for the orbital flight. My activities during this period were very similar to those which I, as the backup pilot, described in a paper on Astronaut Preparation for the MA-6 report. The experience gained as the backup pilot to John Glenn was valuable practice for my own preparation period prior to the MA-7 flight. In the discussion which follows, I will report my observations, sensations, and experiences.


Launch Phase


Insertion into the spacecraft was accomplished without incident, except for a minor problem with the tiedown of the visor seal bottle hose to the helmet. The countdown went perfectly, until the 45- minute weather hold. At T-10 minutes it was picked up again and proceeded perfectly once more until lift-off During the prelaunch period I had no problems. The couch was comfortable, and I had no pressure points. The length of the prelaunch period was not a problem. I believe I could have gone at least twice as long. Throughout this period, the launch vehicle was much more dormant than I had expected it to be. I did not hear the clatter that John Glenn had reported. Once I felt the engines gimbaling. I do not recall hearing the lox venting.

When the ignition signal was given, everything became quiet. I had expected to feel the launch vehicle shake, some machinery start, the vernier engines light off, or to hear the lox valve make some noise, but I did not. Nothing happened until main engine ignition; then I began to fee] the vibration. There was a little it of shaking. Lift-off was unmistakable.

About a minute and a half after lift-off, the sky changed in brightness rather suddenly. It was not black, but it was no longer a light blue. The noise and vibration increased so little during maximum dynamic pressure that it would not be noticed unless you were looking for it. The booster engine cutoff (BECO) was very gentle. Three seconds later, staging occurred. There was no mistaking staging. Two very definite noise cues could be heard: one was the decrease in noise level that accompanied the drop in acceleration; the other was associated with staging. At staging there was a change in the light outside the window and I saw a wisp of smoke.

At tower jettison, I felt a bigger jolt. than at staging, and it was gone in a second. Out the window, the tower could be seen way off in the distance, heading straight for the horizon. It was rotating slowly, with smoke still trailing [70] out of the three nozzles. Just prior to BECO, I noticed a low-frequency oscillation in yaw. This picked up again after BECO and increased very gradually until sustainer engine cutoff (SECO).

At SECO, the dropoff in acceleration was not disturbing . Two separate bangs could be heard: first, the clamp ring explosive bolts, and then, the louder noise of the posigrade rockets. The best cues to the end of powered flight were weightlessness and absolute silence.


Orbital Flight Phase

General Flight Observations


I began the turnaround and wondered why I felt nothing. At this time, the angular accelerations of the spacecraft were not perceptible, and only the blackness of space could be seen through the window. The instruments provided the only reference. The turnaround proceeded just as in the trainer except that I was somewhat distracted initially by the new sensation of weightlessness. I followed the needles around and soon there was the horizon.

Following the turnaround, I watched the expended launch vehicle through the window as it fell behind me, tumbling slowly. It was bright and easily visible. I could see what looked like little ice crystals emanating from the sustainer engine nozzle. They seemed to extend for two or three times the length of the launch vehicle, in a gradually broadening fan pattern.

After the initial sensation of weightlessness, it was exactly what I had expected from my brief experience with it in training. It was very pleasant, a great freedom, and I adapted to it quickly. Movement in the pressure suit was easier and the couch was more comfortable. Later, when I tried to eat the solid food provided for the flight, I found it crumbled in its plastic bag. Every time I opened the bag, some crumbs would come floating out; but once a bite sized piece of food was in my mouth, there was no problem. It was just like eating here on earth.




My only cues to motion were the instruments and the view through the window and periscope. At times during the flight, the spacecraft angular rates were greater than 6° per second, but aside from vision, I had no sense of movement.

I was never disoriented. I always knew where the controls and other objects within the cabin were relative to myself. I could reach anything I needed. I did have one unusual experience. After looking out the window for some time, I noticed that when I turned my head to the right to look at the special equipment storage kit, I would get the impression that it was oriented vertically, or 90° from where I felt it should be. This impression was because of my training in the procedures trainer and lasted only temporarily.

At times when the gyros were caged and nothing was visible out the window, I had no idea where the earth was in relation to the spacecraft. However, it did not seem important to me. I knew at all times that I had only to wait and the earth would again appear in the window The periscope was particularly useful in this respect, because it had such a wide field of view. Even without it, however, the window would have been adequate.


Unusual Flight Attitudes


During the flight I had an opportunity to investigate a number of unusual flight attitudes. One of these was forward inverted flight. When I was pitched down close to - 90°, I think I could pick out the nadir point, that is, the ground directly below me, very easily without reference to the horizon. I could determine whether I was looking straight down or off at an angle. During portions of the second and third orbits, I allowed the spacecraft to drift. Drifting flight was effortless and created no problems.

Alining the gyros consumed fuel or time. The horizon provided a good roll and pitch reference as long as it was visible in the window. On the dark side of the earth, the horizon or the airglow layer is visible at all times, even before moonrise. Yaw reference v as a problem. The best yaw reference was obtained by pitching down -50° to -70° and looking through the window. The periscope provided another good [71] yaw reference at nearly any attitude. The zeropitch mark on the periscope was also a valuable reference for alining the gyros since at zero pitch, the horizon could not be seen through the window. Yaw attitude is difficult to determine at night, and the periscope is of little help in determining yaw on the night side. The best reference is a known star.


Control System Operation


For normal maneuvering in orbit, fly-by-wire, low thrusters only, was the best system. However, I believe for a tracking task, manual proportional control might be more desirable, although I did not actually try it for this purpose. The fly-by-wire high thrusters and the rate command and auxiliary damping systems were not needed for the tasks that I had to perform in orbit prior to preparing for retrofire.

In orbit, the operation of the solenoids of both the high and low thrusters of the fly-by-wire system could be heard. I could hear and feel the rate command system, both the solenoids and the thruster. When using the manual proportional mode, I did not hear the control linkages, but again I heard the thrusters. Through the window, the exhaust from the pitch-down thrusters could be seen. There was no movement, just a little "V" of white steam in front of the window. It was visible even at night.


Balloon Observations


At balloon deployment, I saw the confetti as it was jettisoned, but it disappeared rapidly. I saw one of the balsa blocks and mistook it for the balloon. Finally, the balloon came into view; it looked to me like it was a wrinkled sphere about 8 to 10 inches thick. It had small protrusions coming out each side. The balloon motion following deployment was completely random.

There was no difference between the appearance and color of land, water areas, or clouds from orbit and the view from a high-flying aircraft. (See fig. 7-1.) The view looked to me exactly like the photographs from other Mercury flights. The South Atlantic was 90 percent covered with clouds, but all of western Africa was clear. I had a beautiful view of Lake Chad. Other parts of Africa were green, and it was easy to tell that these areas were jungle.


[MISSING] Figure 7-1.- Examples of interesting cloud formations photographed by Astronaut Carpenter.



There were clouds over the Indian Ocean. Farther west in the Pacific, it was not heavily clouded, but the western half of Baja California, Mexico, was covered with clouds along its entire length. The eastern half was clear. Over the United States on the second orbit, I noticed a good amount of cloudiness, but after retrofire I could see the area around El Centro, Calif., quite clearly. I saw a dirt road and had the impression that had there been a truck on it, I could have picked it out. I did not see Florida or the Cape Canaveral area.


Celestial Observations


Because of the small source of light around the time correlation clock, I was not fully dark adapted, nor was the cabin completely dark; therefore, I did not see any more stars shall I could have seen from the earth. After having seen the star, Corvus, during the flight and later in the recovery airplane, I am convinced that a lot more stars can be seen from the ground than...


72] [MISSING] Figure 7-2.-Sunset as viewed by Astronaut Carpenter in orbital flight.


...I could see through the spacecraft window I could, nevertheless, readily see and identify the major constellations and use them for heading information. I could not see stars on the daylight side if the earth was in the field of view of the window. However, I do remember seeing stars at the western horizon when the sun was just up in the east but the terminator kind not yet et reached the western horizon. The sunrises and sunsets were the most beautiful and spectacular events of the flight. Unlike those on earth, the sunrises and sunsets in orbit were all the same. The sharply defined bands of color at the horizon were brilliant. (See fig. 7-2.)

On the dark side of the earth, I saw the same bright band of light just above the horizon which John Glenn reported. I measured the width of this band in a number of ways, and I also observed it through a special "airglow" filter. A description and analysis of my observations are discussed in the Space Science report (paper 4).

A number of times during the flight, I observed the particles reported by John Glenn. They appeared to be like snowflakes. I believe that they reflected sunlight and were not truly luminous. The particles traveled at different speeds, hut they did not move away from the vehicle as rapidly as the confetti that was deployed upon balloon release. At dawn on the third orbit as I reached for the densiometer, I inadvertently hit the spacecraft hatch and a cloud of particles flew by the window. Since 1 was yawed to the right, the particles traveled across the front of the window from the right to the left. I continued to knock on the hatch and on other portions of the spacecraft walls, and each time a cloud of particles came past the window. The particles varied in size, brightness, and color. Some were gray and others were white. The largest were 4 to 5 times the size of the smaller ones. One that I saw was a half inch long. It was shaped like a curlicue and looked like a lathe turning.


Retrograde and Reentry Phase



I think that one reason that I got behind at retrofire was because, just at dawn during the third orbit, I discovered the source of the space particles. I felt that I had time to get that taken care of and still prepare properly for retrofire, but time slipped away. The Hawaii Cap Com was trying very hard to get me to do the preretrograde checklist. After observing, the particles, I was busy trying to get alined in orbit attitude. Then I had to evaluate the problem in the automatic control system. I got behind and had to stow things haphazardly.

Just prior to retrofire, I had a problem in pitch attitude, and lost all confidence in the automatic control system. By this time, I had gone through the part of the preretro checklist which called for the manual fuel handle to be out as a backup for the automatic control system. When I selected the fly-by-wire mode, I did not shut off the manual system. As a result, attitude control during retrofire was accomplished on both the fly-by-wire and the manual control modes.

At the time, I felt that my control of spacecraft attitude during retrofire. was good. My reference was divided between the periscope. the window, and the attitude indicators. When the retroattitude of -34° was properly indicated by the window and the periscope, the pitch attitude indicator read -10°. I tried to hold this attitude on the instruments throughout retrofire, but I cross-checked attitude in the window and the periscope. I have commented many times that on the trainer you cannot divide your attention between one attitude reference system and another and still do a good job in retrofire. But that was the way I controlled attitude during retrofire on this flight.

Although retrosequence came on time, the initiation of retrofire was slightly late. After [73] receiving a countdown to retrofire from the California Cap Com, I waited 2 seconds and then punched the manual retrofire button. About 1 second after that I felt the first retrorocket fire.

If the California Cap Com kind not mentioned the retroattitude bypass switch, I would have forgotten it, and retrofire would have been delayed considerably longer. Later, he also mentioned an auxiliary damping reentry which I think I would have chosen in any case, but it was a good suggestion to have.

I had expected a big "boot" from the retrorockets. But the deceleration was just a very gentle nudge. The ignition of the rockets was just audible. Retrofire gave me a sensation, not of being pushed back toward Hawaii as John Glenn had reported, but of being slowed down in three increments. By the time the retrofire was over, I felt that there had been just enough deceleration to bring the spacecraft to a stop; but of course, it had not stopped.




Retropack jettison and the retraction of the periscope occurred on time. At this time, I noticed my appalling fuel state and realized that I had controlled retrofire on both the manual and fly- by-wire systems. I tried both the manual and the rate-command control modes and got no response. The fuel gage was reading about 6 percent, but the fuel tank was empty. This left me with 15 percent on the automatic system to last out the 10 minutes to 0.05g and to control the reentry. I used it sparingly, trying to keep the horizon in the window so that I would have a correct attitude reference. I stayed on fly-by-wire until 0.05g. it 0.05g I think I still had a reading of about 15 percent on the automatic fuel gage. I used the window for attitude reference during reentry because of the difficulty I had experienced with the attitude displays prior to retrofire.

I began to hear the hissing outside the spacecraft that John Glenn had described. The spacecraft was alined within 3° or 4° in pitch and yaw at the start of the reentry period. I feel that it would have reentered properly without any attitude control. The gradual increase of aerodynamic forces during the reentry appeared to be sufficient to aline the spacecraft properly. Very shortly after 0.05 g, I began to pick up oscillations on the pitch and yaw rate needles. These oscillations seemed about the same as those experienced in some of the trainer runs. From this I decided that the spacecraft was in a good reentry attitude, and I selected the auxiliary damping control mode. I watched both the rate indicator and the window during this period, because I was beginning to see the reentry glow. I could see a few flaming pieces falling off the spacecraft. I also saw a long rectangular strap going off in the distance. The window did not light up to the extent that John Glenn reported. I did not see a fiery glow prior to peak acceleration.

I noticed one unexpected thing during the heat pulse. I was looking for the orange glow and noticed instead 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 overheating. However, the fact that the rates were oscillating evenly strengthened my conviction that the spacecraft was at a good trim angle. The green glow was brighter than the orange glow around the window.

I heard the Cape Cap Com up to the blackout. He told me that blackout 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.

At peak acceleration, oscillations in rate were nearly imperceptible, since the auxiliary damping was doing very well. The period of peak acceleration was much longer than I had expected. I noticed that I kind to breath n little more forcefully in order to say normal sentences.




At around 70,000 feet, I 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. My best indication of the oscillation amplitude was to watch the sun cross the window and try to determine the angle through which the spacecraft was oscillating. I could feel the change in deceleration as the spacecraft went to one side in yaw or pitch. I switched the drogue parachute fuse switch on at [74] about 45,000 feet. At about 40,000 feet, spacecraft oscillations were increasing. At about 25,000 feet, I deployed the drogue parachute manually when the oscillations became severe. I could see. the drogue parachute pulsing and vibrating more than I had expected. It was visible against a cloudy sky. After the drogue parachute was deployed, I operated the snorkel manually.

I switched the main parachute fuse switch on at 15,000 feet and waited for the main parachute to deploy about 9,500 feet, I manually activated the main parachute deployment switch without waiting for automatic deployment. It came out and was reefed for a little while. I could see the parachute working as the material was stretched taut and then as it undulated after the peak load.. The parachute disreefed and it was beautiful. I could see no damage whatsoever, and rate of descent was right on 30 feet per second.

I was convinced that the main parachute vies good, selected the automatic position on the landing bag switch, and the bag went out immediately. I went through the postreentry and 10,000-foot checklists and got everything pretty well taken care of.

The landing was as much less severe than I had expected. It was more noticeable by the noise than by the g-load, and I thought I had a recontact problem of some kind. I was somewhat dismayed to see water splashed on the face of the tape recorder box immediately after impact. My fears that there might be a leak in the spacecraft. appeared to be confirmed by the fact that the spacecraft did not immediately right itself.




The spacecraft listed halfway between pitch down and yaw left. I got the proper items disconnected and waited for the spacecraft to right itself. However, the list angle did not appreciably change.

I knew that I was way beyond my intended landing point, because I had heard earlier the Cape Cap Com transmitting blind that there would be about an hour for recovery. I decided to get out at that time and went about egressing from the spacecraft.

Egress is a tough job. The space is tight, and the small pressure bulkhead stuck slightly. I easily pushed out the canister, and I had the raft and the camera with me. I disconnected the hose after I had the canister nearly out.

I forgot to seal the suit and deploy the neck dam. I think one of the reasons was that it was so hot. After landing I read 105° on the cabin temperature gage. I felt much hotter in orbit than after landing; and although it was humid, I still felt fine.

I climbed out through the small pressure bulkhead with the raft attached to me. I placed the camera up on top of the recovery compartment so that I could get it in case the spacecraft sank. I left the spacecraft, pulled the raft out after me, and inflated it, still holding onto the spacecraft. I climbed aboard and assessed the situation. Then I realized that the raft was upside down. I climbed back onto the spacecraft, turned the raft over, and got back in.




The sea was quite calm except. for periodic swells, but it was not choppy. The time on the ocean was very pleasant. I drank a lot of water from my survival kit while I was in the raft, but as far as temperature was concerned I was comfortable.

The first thing I saw in the water was some seaweed. Then a black fish appeared, and he was quite friendly. Later, I heard some planes. The first one I saw was a P2V, so I took out the signaling mirror from my survival kit. Since it was hazy, I had some difficulty in aiming the mirror, which is done by centering the small bright spot produced by the sun in the center of the mirror. However, I knew the planes had spotted me because they kept circling the area. Another aid to the planes in locating me was the dye marker which was automatically ejected by the spacecraft. There must have been a stream of dye in the water 10 miles long.

Soon there were a lot of airplanes around, but I just sat there minding my own business. Suddenly, I heard a voice calling from behind me. I turned around and there was someone swimming up to me. I did not even know that he had been parachuted into the water. He inflated his raft, climbed in, and attached his raft to mine. He told me he had parachuted from 1,100 feet and had to swim quite a way to reach me. Later, another swimmer joined us. I broke [75] out the food and asked them if they wanted any; but they had finished lunch recently, and they did not take any.

More aircraft kept circling over us. From time to time, one would drop a smoke bomb marker. A 20-man liferaft was dropped, but the chute failed to open and it hit the water with a tremendous impact. Attached to the raft was another package, containing the Stullken collar, a flotation device much like a life preserver which can be wrapped around the spacecraft to keep it floating. It also hit with a terrific force which, as we learned later, broke one of the C02 bottles used to inflate the collar. The divers started out to get the collar and it took them some time to bring it back. They finally- got back, wrapped the collar around the spacecraft, and inflated it.

When the HSS-2 helicopter appeared, it made a beautiful approach. One of the divers helped me put on the sling, and I picked up my camera which I had previously placed in the recovery compartment. I motioned to the helicopter pilot to take up the slack in the line, and I let go of the spacecraft expecting to be lifted up. Instead, I went down. The helicopter must have settled slightly, because I am sure that there was a moment when nobody saw anything of me but a hand holding a camera clear of the water.

A moment later, however, I began to rise. It was a lift of some 50 to 60 feet. I got into the helicopter with no difficulty and took off my gloves and boots. I poked a hole in the toe of my left sock and stuck my leg out the window to let the water drain out of the suit. When the helicopter landed aboard the carrier, I was in good shape. (See fig. 7-3.) Although I had already had a long day, I was not excessively tired and I was looking forward to describing my experiences to those at the debriefing site.


Concluding Remarks


Overall, I believe the MA-7 flight can be considered another successful step on the road to the development of a useful and reliable manned spacecraft system. The good performance of most of the spacecraft systems gave me...


[MISSING] Figure 7-3.- Astronaut carpenter coming aboard the carrier Intrepid from the recovers helicopter.

 ...confidence in the vehicle itself, while the spectacular novelty of the view from space challenged me to make the most of my opportunity, and lured me into an unwise expenditure of fuel early in the flight. As a result, it became necessary to go to extended drifting flight, and I was able to demonstrate that there was no problem associated with prolonged drifting flight, a procedure we shall have to make use of on the longer duration Mercury flights. I was able to detect and overcome the one significant systems malfunction that might have affected the flight: the malfunction of the pitch horizon scanner circuit. I under stand that many were concerned while waiting without word from me during reentry and after landing. However, from my position, there was no major cause for concern. The spacecraft was stable during the critical portions of reentry and the parachute worked perfectly. For me, this flight was a wonderful experience, and I anxiously await another space mission.