Hello, Blackbird

For more than 25 years, the SR-71 Blackbird carried the eyes in the sky that allowed U.S. military and intelligence agencies to obtain detailed photographs of hot spots around the world.

Now the famed spy plane is carrying cameras focused on the universe above instead of the world below.

Applying Cold War technology to post-Cold War goals, scientists are beginning to use the SR-71, the fastest and highest-flying production aircraft ever, for peacetime experiments.

In March, the Blackbird carried an ultraviolet camera that photographed stars and planets and there are proposals to use the plane to get a clearer look at asteroids, the planet Venus and aurora borealis.

Although the accuracy of the data gathered by instruments carried aloft by the plane must be tested further, scientists agree its potential as a flying observatory is great.

The plane could be used, for example, for experiments to measure the volume of the earth’s ozone layers or the formation of holes in the layer.

The plane could also make it easier for scientists to examine global weather patterns.

“SR-71s can help us solve some of the problems facing us in the 21st Century,” said Jacklyn R. Green, a project scientist for a Jet Propulsion Laboratory program that uses the Blackbird as a scientific research platform.

The Air Force retired the Blackbird in early 1990 and sent most of its 20 remaining planes to museums.

Three of the SR-71s were loaned to the National Aeronautics and Space Administration’s Dryden Flight Research Facility at Edwards Air Force Base for high-speed aeronautical research.

But the planes’ capabilities make them particularly useful for scientists in the fields of planetary science, terrestrial geoscience, astronomy and the like.

The triplesonic SR-71 cruises at an altitude above 85,000 feet and a speed of more than 2,200 m.p.h.

In 1990, a Blackbird set a record flying from Los Angeles to Washington in 68 minutes, 17 seconds.

The top altitude of other planes used for astronomical and scientific research is about 65,000 feet, limiting their usefulness because that elevation still is below much of the Earth’s ozone layer, said Arthur Lane, a JPL research scientist.

The SR-71 flies high enough to get a clearer view of the heavens, Lane said.

Although balloons can reach an altitude of 100,000 feet or more, their path is determined by winds, and a launch costs about $300,000, said Green.

Rockets offer more control but are far more costly, about $10 million per launch.

Satellites are also costly.

The Cadillac of high-altitude research is the space shuttle, but JPL program manager Jim Kelley said it can take years to get an experiment on one of those flights.

“With the SR-71, we’re able to fly a mission that goes where no one else goes, cost-effectively and with low risk,” Green said.

A Blackbird flight costs about $100,000 per hour, including fuel, she said.

Besides its relatively low cost, the SR-71 makes it possible to put instruments aloft quickly when needed.

When a volcano erupts, for example, the plane could take to the sky, equipped with a camera to record volcanic plumes and ash clouds, Lane said.

Ever since word started circulating that the former spy planes could be used for science, interest in the flights has been growing.

Now researchers in other countries are seeking to get their experiments on board.

“Something developed during the Cold War, a strictly military use, is now being used for a non-military civilian thing, and that’s great,” said JPL’s Kelley. “It could be an inexpensive, fast way to test ideas” rather than launching them into space on a rocket while still unproven.

Lane said the plane’s worthiness to science must still be proven.

But the potential, he said, is great. “In certain areas it will allow some major advances to happen,” Lane said. “We think it’s got capabilities that are very important. We believe . . . we will be able to make much more accurate measurements.”

One issue to be studied is how the plane’s tremendous speed affects the data it collects.

Scientists would like to know, for example, how the high air temperature generated by the plane’s passage affects the delicate sensing instruments and the data they collect.

An SR-71 flew twice in March with an upward-looking ultraviolet camera system installed in its nose bay.

The first flight, on March 9, was intended to ensure that the camera, called SWUIS for Southwest Ultraviolet Imaging System, would operate at Mach 3.

During the 90-minute flight, which began and ended at Edwards AFB in the Antelope Valley, the plane cruised at an altitude of 83,000 feet over Nevada, Arizona, New Mexico and Utah.

Vibrations were not detected in the camera, according to Green.

Alan Stern of the Southwest Research Institute in San Antonio, said the ultraviolet camera was built as a shuttle payload for photographing planets.

It may be flown aboard one of the orbiters in late 1994 or early 1995.

The scientific results produced by an SR-71 flight do not compare with the potential of a shuttle flight, he said, but the SR-71 flights are far more readily available.

“For some applications it’s the way to go,” Stern said. “I’ve been in the space business 15 years. There are some things you can do on this airplane That you can’t . . . without getting into space.”

Green, a planetary scientist, was among the first to pursue use of the plane for high-altitude science.

Fifteen months ago Green was having lunch with a fellow scientist at the Jet Propulsion Laboratory in Pasadena when she learned Dryden had three Blackbirds.

“I thought, ‘Gee, that’s a really cool plane,’ ” said Green, who initially thought the Blackbird could be used to help her collect interplanetary dust particles.

Although she had used lower and slower planes for that purpose, she thought the SR-71 would work better.

When Green learned that no other scientists were using the planes for such projects, she took on the cause. “Once I saw the airplane, I said, ‘We can’t let it go.’ ”

Instead of collecting dust particles, she is focused on broadening the plane’s use in research.

Green is drumming up support among scientists with the goal of attracting funding for the flights.

NASA has agreed to dedicate one of the Blackbirds for full-time research.

The space agency is allowing the JPL science program to piggyback on their aeronautics research flights until funds are available for full-time research, said Dave Lux, the SR-71 project manager at Dryden.

Dryden’s annual budget is $3 million, which allows 25 to 30 flights per year.

Crews are now installing an optical air data system, or OADS, for a Blackbird flight in mid-June, the third on a scientific mission. OADS uses a laser to measure the speed of aircraft.

“SR-71s are part of what we are,” Green said. “They helped us win the Cold War. Now we can give them a new life.”

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