KUIPER AIRBORNE OBSERVATORY
taxi, takeoff, and ascent, aircraft vibrations are transmitted with little
damping throughout the telescope structure. About five to ten minutes
before observing is to begin, the Telescope Operator at the Main Console
begins activating the telescope stabilization system. First, the four
vibration isolators are activated. The telescope is then "up on isolators"
and partly insulated from aircraft vibration. After airflow around the
air-bearing is started, the telescope may be "uncaged". Linear uncaging
allows the telescope to be "floating" on the air-bearing. Rotary uncaging
permits slewing of the telescope to the desired elevation angle. Unless
balance is being checked, the telescope will be gyro-stabilized when it
is floating. The telescope must be caged before the aircraft turns onto
a new heading.
- The Gerard P. Kuiper Airborne Observatory (KAO)
is a national facility operated by the National Aeronautics and Space
Administration to support research in infrared astronomy. The observation
platform is a highly modified C-141A jet transport aircraft with a range
of 6000 nautical miles, capable of conducting research operations to
45000 feet (14 km).
The KAO's telescope is a conventional Cassegrain
reflector with a 36-inch (91.5 cm) aperture, designed primarily for
observations in the 1 to 500 micron spectral range. The telescope
looks out the left side of the aircraft at an elevation of between
35 and 75 degrees.
The KAO is based at the Ames
Research Center (aerial
view - 583 KB) at Moffett Field, California (near San Jose, CA).
It is operated as a facility for scientists whose proposals have been
deemed suitable and have been approved by NASA. Those scientists perform
research with scientific instruments which have often been developed
especially for use on the aircraft. Each instrument may be installed
on the aircraft for a few days to several weeks, allowing multiple
flights and investigators using the same instrument.
Ames Fact Sheet provides considerable basic information about
- The KAO performs astronomical observations analogous
to those made in ground-based or space-based telescopes. The KAO's observing
capabilities fill a unique niche in astronomical science, however. Its
flight capability allows it to rise above much of the water vapor in
the earth's atmosphere (allowing observations of infrared radiation
which is blocked before reaching ground-based facilities), as well as
travel to almost any point on the earth's surface for an observation.
At the same time, in between flights the facility is ground-based, allowing
systems development, maintenance, and repair.
To perform astronomy while in flight, a number of systems must work
together to provide a stable observation platform. Several sub-systems
or steps are involved in this process. They include:
Each of these is described in further
detail, and the use of the systems as a unit provides a lesson on
KAO Telescope Operations.
- the aircraft autopilot
- the vibration isolation system
- the spherical air bearing
- the gyro-stabilization system
- the video star tracker
telescope aperture door is normally kept closed until the aircraft is
at 35,000 feet or higher. After the flight crew have leveled off the
aircraft at the initial assigned altitude, the door is raised to expose
the telescope. Opening the door takes about two minutes. After the Mission
Director receives verification from the flight deck that the aircraft
will remain level and is on the correct heading, the Telescope Operator
may uncage the telescope and transfer control from the Main Console
to the forward joystick and Tracker Console. The Tracker Operator or
the Investigator will then have control of the telescope for fine pointing.
The aircraft began as a Lockheed Model L300 Starlifter
jet transport, originally configured as a prototype commercial version
of the U.S. Air Force C-141A. The telescope system was designed and built
by the Fecker Systems Division of the Owens-Illinois Corporation. The
telescope cavity was designed and installed by Lockheed Aircraft Services
in May 1973. Research operations began in February, 1974, and the facility
was dedicated as the Gerard P. Kuiper Airborne Observatory (KAO) in May,
The information on this page was taken from the Kuiper
home pages by Florentino.
Here is information about the original KAO