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NASA Program to Study Lightning Effects Is Almost a Flash in the Pan : Science: An uncharacteristic lack of storms for Florida frustrates researchers. But some experiments inspire massive electric discharges.

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ASSOCIATED PRESS

It’s unusually quiet these days on the swampy shores of Mosquito Lagoon, hangout for mosquitoes, rattlers, gators, bobcats, boars and--every summer and fall--lightning researchers.

Animals abound, but most of the scientists and engineers have left, frustrated by a dreary year at NASA’s Ft. Lightning.

First there was the security crackdown, right at the height of storm season. Sightseers strayed too close to the stockaded area from which small rockets, trailing copper wire, were being launched into thunderstorm clouds to trigger lightning.

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Then the skies cleared and stayed clear. Storms swirled everywhere but over the lagoon.

A giant weather balloon on loan from the Navy was ripped from its moorings by 55-m.p.h. winds in August and landed in the Atlantic Ocean. Researchers salvaged it. Two weeks later, a 4 1/2-foot Mighty Mouse rocket ignited too early, injuring a French engineer and resulting in a suspension of launch activity.

That was the last time a rocket roared from the research site on the western bank of the lagoon, part of the national wildlife refuge that makes up Kennedy Space Center.

The 12 stainless steel tubes for launching smaller, less powerful rockets from the top of a two-story wooden platform still are filled. But the gunpowder can’t be lit until a space center investigative team recommends corrective action. One option is moving the field laboratory to an even more isolated spot.

“Everything went to pot, including the weather,” said Bill Jafferis, manager of Kennedy’s rocket-triggered lightning project.

“We had only one good storm this summer, only one,” lamented Andre Eybert-Berard, head of the French research team.

But what a storm it was. The researchers sent 12-yard-long rockets with wire spools soaring a mile into the air on Aug. 10. Nine of them triggered lightning; the electric discharges hurtled down the vaporized copper wire anchored to the pad. Ground instruments monitored the strokes as well as the electrical fields from which the bolts burst.

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“It’s a real kick in the pants to be out there and have lightning hit within 100 feet of you,” said NASA engineer Don Conover, second in command at the fort. “It’s the craziest thing I’ve ever been involved with.”

“This definitely goes contrary to typical launches,” said Dave Curtis, an aerospace engineer at Hanscom Air Force Base, Mass. “You never want to trigger lightning. We try to stay as far away from lightning as we can.”

Altogether, 35 rockets were launched from the site over the summer, about two-thirds the normal. Twenty-two of them triggered lightning and provided “reasonably good results” for the approximately 35 researchers from around the world who took part in this year’s program, Jafferis said.

Vince Idone, an atmospheric physicist at the State University of New York at Albany, is trying to gauge the diameter of lightning by using a streak camera that continuously records the electric discharges and allows for measurements every three-millionths of a second. He went home with two lightning flashes captured on film.

Jafferis has been whipping up lightning for NASA in central Florida, America’s lightning capital, since 1983. The French were invited because of their expertise; Eybert-Berard triggered his first lightning in 1973 and has an estimated 700 launches to his credit.

The National Aeronautics and Space Administration moved the operation in 1985 to Mosquito Lagoon, an unrestricted area 10 miles north of the shuttle launch pads. A wildlife trail meanders along the site, and a public boat-docking area is tucked behind dense scrub.

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Towering over the wooden launch platform, inside the stockade, is a gallows-like structure made of 50-foot poles. Canisters and other objects designed to simulate rockets occasionally are hung from the crossbeam and zapped by lightning zooming down the half-mile or so of rocket wire. A canopy of crisscrossing metal wire provides grounding.

Within 150 feet of the stockade, surrounded by waist-high weeds, are a yellow caboose covered with sandbags for protection and four white, windowless trailers where researchers huddle with their equipment at launch time. An empty guard shack is the frequent target of a lightning simulator, which produces 15-foot-plus sparks.

Before security managers scrutinized the site early this summer, “it looked like a junk pile,” Conover said. “It still doesn’t look all that professional.

“At times, I’m ashamed when I see the conditions of things and follow people (sightseers) who throw garbage on the ground,” Conover said. “But at other times, I’m proud that we’re contributing to science.”

The aim of the $200,000-a-year program is to shed more light on lightning to better protect spacecraft--both on the ground and en route to space--as well as buildings and power lines.

Apollo 12 vividly demonstrated the need to know more. Seconds after the Saturn 5 cleared the pad on Nov. 14, 1969, two lightning flashes streaked to the ground. Most of the electrical power was knocked out, but backup batteries automatically came on-line, and the ship went on to the moon.

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Nearly 18 years later, on March 26, 1987, a lightning strike upset a computer on an unmanned Atlas-Centaur rocket bound for space with a military communications satellite. The computer issued a sharp swerve command that tore the rocket apart a minute into flight.

In both cases, the rockets entered high electrical fields and triggered their own lightning. That’s what Jafferis, Conover and company strive for every time they send up one of the plastic blue and yellow rockets supplied by the French.

Their piece de resistance is a bolt that packed a record 100,000 amperes on Sept. 26, 1989.

“It was so cool,” Conover said wistfully as he played a videotape of it one slow, stormless day.

Less dramatic, but far more common, is lightning’s effect on launch work.

Storms interrupt launch preparations several times a week during the summer and fall, sometimes several times a day. Workers must evacuate the pads when lightning threatens within 5 miles. This accounts for an 8% to 10% loss in work time, studies show.

Thirteen of 18 shuttle launches have been delayed or canceled by bad weather since the resumption of manned space flights in September, 1988. The strict weather criteria is a result of the Challenger accident, which occurred 73 seconds after liftoff on a frigid morning in January, 1986. All seven aboard were killed.

Despite all the outdoor activity and central Florida’s propensity for thunderstorms, only three people have been killed by lightning at the space center over the years--a guard, a construction worker and a beach sunbather.

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Unraveling the mysteries of lightning, and thus improving forecasting, can reduce unnecessary interruptions and launch delays and save money, equipment and lives, Jafferis said.

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