There will be more questions than answers for weeks, if not months, to come.
But one conclusion is certain, regardless of what happened on the outside or inside of the space shuttle Columbia.
Technology has its limits. Information systems have their limits. Human analysis, foresight and insight have their limits. This is not the last time a set of explorers will perish in a journey to or from outer space.
Take the foam. This was the piece of insulation on an external tank that appeared, according to NASA, to “impact the orbiter” on its left wing during liftoff. In the 48 hours after the breakup, signs seemed to point to intense heat on the left side, indicating tiles there were not doing their job of shielding against the 3,000-degree temperatures of re-entry.
Shuttle program manager Ron Dittemore said the prospect for damage to the tiles was evaluated and discounted by experts shortly after it occurred, early in the orbiter’s flight. NASA and its experts, he said, understood tile.
The foam was being discounted again, four days after the tragedy. But debris is a perpetual problem.
Several years ago, insulation was erupting like popcorn, “impacting” tile. The damage was superficial and the problem fixed. Yet, a couple of flights ago, debris was shedding again. The red flag should still be raised.
“Two occurrences in the last three flights is certainly the signal to our team that something has changed.” Dittemore said, after the Columbia broke up.
What has changed is still not known. And as this issue goes to press, the cause of the disaster remains a mystery.
Which makes one of the big unanswered questions: If the best scientists in the world can’t link independent variable x (the cause of a problem) to dependent variable y (the safety of a vehicle) from available data, shouldn’t more analysis be performed on the vehicle itself?
This can start with visual inspection. In this flight, the crew was not fully trained in space walking. NASA had determined that asking a crew in space to replace tile might end up causing more damage than it fixed. So crews aren’t sent up with the knowledge, preparation or repair kits to address this eventuality.
Of course, there is an international space station orbiting the earth. One of its purposes should be to act as a mechanic shop in the sky. But this space shuttle was not built with the proper means of attaching to the station, NASA says. So this was not an option.
In this instance, NASA wanted the shuttle crew to take pictures of the tank, to understand exactly where the foam was shed. Then, when they got the hand-held film back, upon return to ground, the pictures would be analyzed for a flight readiness review.
Why, pray tell, are we still waiting for hand-delivery of film? And later analysis? The means should be on board for such images of any potential point of vulnerability to be taken and sent back immediately.
We also live in an era of sensors that can grab all sorts of information and send it back in a constant stream. Shuttles already use lots of them. Yet the real event that raised concern was…when the sensors went off, like the cutting of wire on a telephone.
A day after the Columbia was lost, NASA acknowledged temperatures on the shuttle’s left fuselage escalated 60 degrees six minutes before the vehicle broke up. In this day and age of double gigahertz processors and cheap-as-dirt detectors of all types, we should be able to feed huge amounts of data into an intelligent system that generates not just alerts for humans on the ground and in the sky, but answers and potential prescriptions that help crews prevent conditions from getting worse.
This event suggests our early-warning and data collection-systems are not early or accurate enough; and should be part of a careful re-examination of how we conduct flights in space.
Tom Steinert-Threlkeld
Editor-in-Chief
[email protected]
