The Orlando Sentinel


By Joe Newman
The Orlando Sentinel

Tuesday, February 4, 2003

As tragic as the Columbia disaster is, it could have been much worse if debris had rained down on the Dallas area, with its 3.5 million people, or some other heavily populated area in the shuttle’s path.

Instead, the majority of the pieces fell onto sparsely populated Nacogdoches County—population 59,000.

But while President Bush and NASA Administrator Sean O’Keefe expressed amazement that no one was struck by debris, the thanks goes more to the prevailing winds and pure luck than any carefully planned NASA trajectory.On its way down, Columbia passed high over Southern California and Arizona before it began disintegrating 207,000 feet over Texas.

If it had continued descending, it would have glided over Dallas and near New Orleans before curving along the Florida Panhandle into Central Florida on its way to landing at Cape Canaveral. Until Saturday, very few people worried about the dangers a disaster on re-entry might pose to those below.

“To my knowledge, I don’t think we’ve ever really studied the breakup of the shuttle on re-entry,” said Robert Eleazer, an engineer with ACTA, a California company that has a contract with the Air Force. ACTA has developed computer models showing what happens when spacecraft, including the space shuttle, break up during a launch.

However, when it comes to re-entry, the shuttle is considered no more dangerous than a jumbo jet, Eleazer said. “The bottom line is between a DC-9 falling out of the air and the space shuttle—there’s not any difference,” Eleazer said.

“Launch is obviously a much greater hazard.” For launches, there’s a whole different level of anxiety compared with when the space shuttle returns to Earth, mainly because of the millions of gallons of rocket fuel strapped onto the shuttle.

If something goes wrong at liftoff, there are computer models showing where the wind might carry debris and gases. Hazardous-materials teams and emergency crews are on alert. There’s even a self-destruct button that can be used if the shuttle veers toward a populated area.

But federal emergency management officials, as well as state officials in Texas and Florida, were unaware of any specific contingency plans for a shuttle disaster on re-entry. “We have emergency preparedness plans for all sorts of incidents and disasters,” said William Ayres, a spokesman for the Texas Emergency Management division. “I don’t think we have a plan for a shuttle breaking up over us.”

In Brevard County, officials are always “aware” that the shuttle is returning, but there’s no specific planfor what to do if it crashes. “It’s just like an airliner. Do we have a plan if an airliner breaks up in the air?” said Bob Lay, Brevard Emergency Management director. But in the case of a shuttle breakup, there are hazardous materials to worry about that aren’t aboard a typical airliner.

One of the biggest concerns is a chemical called hydrazine, the propellant used to power the thruster rockets. It is highly toxic, has been linked to cancer and can cause temporary blindness and respiratory problems. Officials have warned people not to touch any shuttle pieces they encounter for fear they might be tainted with hydrazine or some other chemical.

“What has happened with this shuttle disaster, unfortunately, is you have a scenario where this very dangerous compound has been dispersed,” said Mike Shaw, an official with Interscan, a NASA contractor. The Los Angeles company makes the sensors that are used at the launch pad to detect hydrazine leaks. “If people come in contact with it, it can be very nasty, very quickly,” Shaw said.

“There’s also a good chance that the fuel was dispersed into the atmosphere”, said Russell Prough, a biochemist at the University of Louisville who has researched hydrazine. But the hydrazine would be high enough in the atmosphere that it poses no immediate threat to people on the ground,” he said.

Eleazer, the ACTA engineer, also said it was unlikely that any hydrazine made it to the ground. “It’s more likely that the rocket fuel burned up in the atmosphere,” he said. “The one danger might be that a fuel container may have come to Earth intact,” he said. “While there’s plenty that’s still unknown about the accident, researchers, including himself, are already working on computer models to answer those questions,” Eleazer said.