NASA X-38 Team Flies Largest Parafoil Parachute in History

James Hartsfield

Johnson Space Center, Houston, TX

(281) 483-5111

Release: J00-9

A team developing a prototype International Space Station “lifeboat”
called the X-38 Crew Return Vehicle successfully flew the largest
parafoil parachute in history last week at the U.S. Armyís Yuma Proving
Ground, Arizona, as they released a parachute with an area almost one
and a half times as big as the wings of a Boeing 747 jumbo jet.

The unmanned Jan. 19 parafoil test was part of the development of a
re-entry system for the X-38 spacecraft. With an innovative combination
of old and new technology and a streamlined development, the goal of the
X-38 team is to develop a new human spacecraft for a fraction of the
cost of any past program. Plans are to develop and build four
operational X-38-based International Space Station Crew Return Vehicles
for less than half of what it cost to manufacture a single Space Shuttle
orbiter. The X-38 may become the first new U.S. human spacecraft to fly
to and from space in more than 20 years. The parafoil recently tested in
Arizona has a span of 143 feet and a total surface area of 7,500 square
feet, making it the largest parafoil in the world.

ìI think this is a world’s record for a parafoil and it is a significant
milestone and accomplishment for NASA,” said John Muratore, who is
leading the X-38 Crew Return Vehicle Project. “It puts us a major step
closer toward our goal of providing the space station with the most
flexible crew return option. This parafoil has the size and all the
features to enable it to be used for returning humans from space.î

For the test, an 18,000-pound pallet, simulating the actual X-38, was
dropped from the back of a C-130 aircraft at an altitude of 21,500 feet.
A 28-foot diameter extraction parachute pulled the test platform from
the aircraft at an air speed of 130 miles per hour to begin the flight
test. Once out of the aircraft, a newly designed 80-foot diameter drogue
parachute stabilized and slowed the platform to a vertical airspeed of
62 miles per hour and enabled the parafoil to begin a five-stage
deployment process. During its 11-minute long flight, the parafoil
slowed the test pallet to a gentle vertical landing speed of less than
eight miles per hour.

ìThis parafoil is so big there is no way that it can all deploy at
once,î said Brian Anderson, X-38 Project Manager. ìBecause of its size,
the dynamic forces on the parachuteís structure are phenomenal.î The
size of the parafoil posed technical challenges for the X-38 team. One
problem encountered in past tests has been to ensure that the parachute
opens evenly. To solve this and make certain that the parachute opens
symmetrically and rapidly, the team developed a revolutionary
self-sealing floor vent system on the parafoil’s underside. During the
recent test, the parafoil opened to its full size in only 30 seconds.
The parafoil was stitched together at Pioneer Aerospace’s facility in
Columbia, MS. Because of its unprecedented size and strength, personnel
at Pioneer nicknamed the parafoil “Sampson.” A unique ripstop nylon
material, customized stitching and other safety devices incorporated
into the parafoil make the parachute not only the world’s largest but
also among the strongest.

“The strength and quality of this parafoil is a real testimony to the
skill and dedication of the men and women who built it,î Muratore said.

The test was the 30th large-scale flight test conducted to support
development of the parafoil, although this was the largest and most
comprehensive test to date. In addition to tests at Yuma, four
large-scale atmospheric flight tests of prototype X-38 vehicles have
been completed at NASA’s Dryden Flight Research Center using a smaller
5,500 square-foot parafoil. For those tests, increasingly complex X-38
vehicles have been launched from a B-52 carrier aircraft at increasingly
higher altitudes. More such tests are planned during the next year and a
half, leading up to a space flight test of the X-38 in 2002, when an
unmanned vehicle now under construction at the Johnson Space Center will
be released in orbit by the Space Shuttle to fly back to Earth.

The X-38’s design is called a lifting body. Unlike the space shuttle, it
does not have any wings. All of the lift necessary to maneuver and fly
the X-38 comes from the lift generated by the flow of air over the body
of the spacecraft and its fins. Lifting body configurations were studied
extensively in the 1960s and 1970s as space entry vehicles. These
vehicles all had very high landing speeds that proved difficult to
control. The combination of the lifting body for the high speed part of
entry followed by the parafoil for the final landing have proven to be a
winner in the X-38 project. The large-scale drops of the parafoil were
supplemented with well over 300 subscale drops.

ìThe subscale drops gave us the opportunity to test and refine
techniques and gain the experience we needed for the large-scale drops
at a much lower cost,î said Jenny Stein, Project lead for the X-38
parachute systems. The 7,500 square-foot parafoil will be tested at Yuma
again this spring and will then be integrated with one of the X-38
vehicles at Dryden for a test flight there late this year. *** NOTE:
NASA photographs 7663-17, 7664-15 and 7665-15 can be downloaded from the
internet to illustrate this release. They, along with other X-38 photos,
are available at
http://spaceflight.nasa.gov/gallery/images/station/crvx38/ndxpage1.html
Video to accompany this release will air on NASA-TVís Videofile at 11
a.m., 2 p.m., 5 p.m. and 8 p.m. CST today or can be obtained by
contacting the Johnson Space Center Media Resource Center at (281)
483-4231. NASA-TV can be accessed through GE2, transponder 9C. The
frequency is 3880 Mhz with an orbital position of 85 degrees West
Longitude, with audio at 6.8 MHz.

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