ASCANs received hypobaric training in the hypobaric chamber located in
the Astronaut Training Facility, Tsukuba Space Center. This training was
conducted to enable them to understand and experience physiological changes
in a hypobaric environment and to acquire means to deal with them. The
hypobaric chamber is composed of a low-pressure chamber, data collection
system, pressure control facility, air conditioning facility, and operation
and control facility. This system can accommodate a maximum of six people
to a minimum pressure of 0.2 atmospheres.
This training must be conducted before the weightless environment training
using NASA's KC-135A. They conducted the training pattern of lowering the
pressure from ground level (one atmosphere) to 35,000ft (0.24 atmospheres)
and back to one atmosphere again. The ASCANs removed their oxygen masks
to experience a low-oxygen environment and the change in night vision,
and conducted emergency oxygen breathing training and emergency decompression
Operations control facility
Gravity change due to a parabolic flight
Having finished hypobaric training, the ASCANs participated in weightless
environment training using a KC-135A jet in Houston Texas. This training
was conducted to enable the ASCANs to experience a weightless environment,
to understand body movement and control, and physical phenomena. Another
purpose was to enable them to understand and experience the difference
between the weightless environment utilizing water buoyancy they experienced
during the EVA training conducted in February this year.
During the 40 parabolas, they experienced weightlessness through body movement
and control, and watched various physical phenomena. They also observed
motion of balls and tops under weightless environment.
A weightless environment is the state of being affected only by the gravity
and where no other force is applied. During weightless environment training,
utilizing an aircraft, the aircraft is flown in a parabolic pattern, which
creates a temporary weightless environment inside the aircraft.
To create the maximum period of weightlessness, the aircraft is accelerated
to maximum speed just prior to the start of parabolic flight. Its nose
is then pulled up suddenly and the engines power is lowered to allow the
aircraft to follow a parabolic trajectory. To ensure safe recovery of normal
flight, the engines power is increased before the nose is oriented below
40 degrees, and the nose is pulled up to resume normal flight. This action
The KC-135A jet can generate about 25 seconds of weightlessness during
one parabolic flight. People sometimes feel sick, which is why some people
call this aircraft the "Vomit Comet."