 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.
Most recently, they conducted a study on the deposition of small aerosol particles in the
lung. The subject breathed continuously through a mouthpiece connected to a valve system from which breathed
either room air or aerosol. The aerosol concentration and flow rate were measured by a photometer and
pneumotachograph (flow meter). In the first set of flights, four different aerosol sizes, from 0.5 micron to 3
micron, were used, and a comparison was made looking at how much deposition occurred as a function of gravity
level for each particle size. The particles used were spherical latex particles, so they were non-toxic and
harmless to the lung.
View some pictures
from these flights. |
