This occasional column explores topics covered in Science Times 25 years ago to see what has changed, and what has not.
The National Aero-Space Plane was to be a revolutionary advance beyond the space shuttle.
In his 1986 State of the Union address,
President Ronald Reagan promised “a new Orient Express that could, by
the end of the next decade, take off from Dulles Airport and accelerate
up to 25 times the speed of sound, attaining low-earth orbit or flying
to Tokyo within two hours.”
On
Oct. 3, 1989, an article in Science Times, “Designing a Plane for the
Leap to Space (and Back),” reported frenetic activity at NASA and the Defense Department.“Scientists and engineers are making rapid progress in developing
technologies needed to build a 17,000-mile-an-hour ‘space plane’ that
could escape earth’s gravity and circle the globe in 90 minutes,” the
article began.
“Their
goal,” it continued, “is a space plane that could take off and land
from virtually any airport in the world, carry satellites and other
space cargo into orbit cheaply, shuttle between the earth and an
orbiting space station, or carry a load of bombs deep into enemy
territory as fast as an intercontinental missile.”
Proponents contended the space plane would be far cheaper to operate than the shuttle.
Others
were dubious. The Air Force, which was providing most of the financing,
had already tried to back out, but the National Space Council, headed
by Vice President Dan Quayle, recommended continuing work at a slower
pace.
The
target for the first flight of the first experimental version, known as
the X-30, was originally 1993 but was pushed back to 1997.
25 YEARS LATER
The space plane, able to fly by itself to orbit, never took off. The
X-30 died in 1994. Smaller-scale hypersonic programs came and went.
Was the X-30 technologically feasible?
“No, and it’s still not,” said Jess Sponable, a program manager in the tactical technology office at Darpa,
the Defense Advanced Research Projects Agency. For X-30 to succeed,
infant ideas would have had to have been developed into robust, reliable
technologies — materials that could survive intense temperatures,
air-breathing engines that could fly faster and higher.
Nonetheless,
“absolutely, it was worthwhile,” Mr. Sponable said, although he added
perhaps not worth the more than $1.6 billion spent. “We learned a lot.”
The pendulum for spacecraft design has since swung away from the cutting edge to the tried and true. The Orion craft, which NASA is building for deep-space missions, is a capsule, just like the one used for the Apollo moon
missions but bigger. The two private company designs that NASA chose to
take future astronauts to the space station are also capsules. (The
loser in that competition was a mini-shuttle offering.)
But the dream of hypersonic space planes continues.
At
Darpa, Mr. Sponable heads the XS-1 space plane project. It is not a
do-it-all-at-once effort like the 1980s space plane but a much simpler,
unmanned vehicle that would serve as a reusable first stage.
Mr. Sponable is eager to figure out how to send it up many times, quickly and cheaply; the goal is 10 flights in 10 days.
“We
want operability No. 1,” he said. With the quick launches, the issue of
cost “just disappears, because we can’t spend a lot of money from Day 1
to Day 2 to Day 3.”
Darpa
has awarded contracts to three industry teams to develop preliminary
designs. Mr. Sponable said the decision of a next step would come next
spring.
The
space plane episode illustrates the recurring money woes that have
bedeviled NASA for decades: A grandiose plan is announced with fanfare
and a burst of financing that fades as delays and cost overruns undercut
the optimistic plans. Then a new president or a new NASA administrator
changes course.
Most recently, the Obama administration canceled plans started under President George W. Bush to send astronauts back to the moon and told NASA to consider an asteroid instead.
If the pattern continues, NASA priorities could zig again after the next president moves into the White House in 2017.
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