| The KC-135 is a NASA airplane which provides a special opportunity to perform
experiments in microgravity. The plane flies in parabolas, resulting in 2-g during the pullout, and 0-g for a
period of 25-30 seconds over the top. The plane is used for 0-g experiments, as well as for astronaut training.
A typical week of flying will be 40 parabolas a day, four flights per week. To those who have experienced the
thrill of floating, the KC-135 is fondly known as the "Vomit Comet."
 The UCSD Physiology/NASA lab has conducted several experiments aboard the KC-135 plane.
From the four aerosol sizes studied in the first set of flights,
the 1-micron size was chosen based on its medium range of deposition. For the next set of flights, the subject
inhaled a full breath from residual volume (out as far as he or she can go) all the way up to total lung
capacity (up as far as he or she can go). A bolus (small volume) of aerosol was inserted by the valve
system into the breathed air at different times in the inspiration (one bolus per test). The subject then
exhaled back out to residual volume, and the deposition was seen to change depending on how early in the
inspiration the aerosol was introduced. The data from the flights will be compared to data taken on each subject
on the ground, to see how aerosol deposition changes in 0-g and 2-g compared to 1-g.
See the Publications Page for some of the
published results from these experiments. |
