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Astronaut Candidates 2004: | Home | Journals
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Astronaut Candidates 2004
IMAGE: Members of NASA's 2004 class of astronaut candiates aboard a KC-135
A number of NASA's 2004 class of astronaut candidates and some JAXA astronauts tumble during one of a series of reduced gravity sessions provided by special parabolas flown by a KC-135 aircraft.
*Astronaut Candidates 2004 Imagery
*Zero-Gravity Plane on Final Flight

Astronaut Candidates 2004 - Training Journals

Journal #8
October 11 - 15
, 2004

On October 13, we had the opportunity to experience a simulation of reduced-gravity as well as Martian and lunar gravity in NASA's KC-135 "Weightless Wonder," which is affectionately known as the "Vomit Comet." NASA's KC-135 is basically a modified cargo jet with an empty (and heavily padded) fuselage. It takes passengers and payloads out over the Gulf of Mexico where it simulates various gravity scenarios by flying in parabolas. The plane climbs up at a very steep angle for several minutes then the pilot lets the nose fall over sending the plane into a steep dive toward the Gulf of Mexico. Anything or anyone inside the plane falls to the ground at the same rate, thus simulating weightlessness. Changing the shape of the dive or parabola allows researchers to simulate the gravity of the Moon or Mars. We were fortunate to fly the KC-135 when we did, because the plane flew its last flight on October 29 and was officially retired a couple of days later. NASA will soon be replacing the KC-135 with a DC-9.

Some common questions we've heard following this training were, "How did it feel?" or "What was it like?" Here are some descriptions from the Astronaut Class of 2004:

  • "First you feel the blood rising in your chest and in your face, and then you realize your feet aren't touching the ground anymore, and that you're headed for the ceiling. Once you get the hang of flying the length of the plane, you start to think of your feet and legs as trailing behind you, instead of being under you. And during each trip down the plane, you're surrounded by blue flight suits, all in different orientations, arms and legs everywhere, and everyone smiling and laughing."
  • "We'll be supporting many efforts to determine if certain tasks can be accomplished in zero-G. In order for us to be able to focus and do a good job on these zero-G investigations, we need to make sure we know how to respond, move, and restrain ourselves in the zero-G environment. We all learned a lot about that last Wednesday."
  • "My initial reaction to the zero-G was a feeling of being upside down. I knew that the plane hadn't just rolled 180 degrees, but my brain was telling me to flip over – and that was with me still holding onto the arm rests of my seat!"

    "I was also surprised by how hard you could hit the wall on the other side of the plane with a seemingly 'light' push-off."
  • "I thought the feeling of absolute freedom of movement was amazing. It is hard to put into words to describe the feeling of being able to 'Superman' from one end of the plane to the other."

    "I also thought, after all our individual T-38 training, that it was really special to be able to experience weightlessness together as a class."
  • "It was very interesting. At first it was a challenge to balance and control my body in zero-G. But we can get accustomed to the new environment quickly. As time passed, I got more and more comfortable moving around in zero-G. I look forward to the day when people will live in a different gravity environment."
  • "My favorite part of the zero-G experience is the feeling of total freedom--moving in any direction with no 'up' or 'down'. I also enjoyed the ease at which I could do push-ups on the lunar and Mars parabolas."
  • "Because I have flown near zero-G many times in my flying background, I was not expecting the Vomit Comet to be too different from my previous experiences. Was I ever wrong! As I discovered, there is a huge difference between being strapped into a seat during zero-G and being able to float around. The biggest thing that stood out to me was the freedom I felt being able to make the smallest push from a surface and find myself cruising effortlessly through the cabin. I also caught a small glimpse of how difficult the simplest tasks could be to perform in space--trying to spin one of my classmates while he was curled up in a ball, I found myself spinning and twirling despite trying to stay restrained. I also bonked his head off the floor--sorry about that! He did a much better job spinning me. The most fun thing to do was lying on the floor at the far end of the jet and pushing off to 'fly' the entire length of the KC-135 cabin. A close second, though, was the game of football we played while on Mars (simulating Mars gravity) and the resulting melee that broke out in the middle of the jet with everyone tackling and wrestling each other. Overall, it was an incredible experience--a great motivator for the training we have ahead."
  • "Experiencing microgravity was one of the most awesome experiences of my life. It was great to not have the constraints of gravity. It is like SCUBA diving without any of the gear. Even more than before, I can't wait to travel in space."
  • "I found the most interesting thing was how we responded so differently to zero-G than lunar gravity. When the zero-G parabolas started, many of us didn't know quite what to do as the sensation was new to us. Once we got comfortable, we started trying to do the things you can't do here on Earth, like flying the length of the plane or running around the diameter of the fuselage. Once we started the lunar and Martian parabolas, everyone started doing things they could do on Earth, like playing football or wrestling because it was so easy…..and fun. I remember Captain John Young telling our class how 'nice' it was to work on the Moon. The trip on the KC-135 really demonstrated why it is familiar enough to Earth that your actions are the same but the reduced gravity just makes it that much easier!"

- The Astronaut Candidate Class of 2004

Curator: Kim Dismukes | Responsible NASA Official: John Ira Petty | Updated: 03/25/2005
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