Magnetic tape inside a data recorder recovered last week in Texas appears to be in remarkably good shape, despite the stresses it experienced during the shuttle Columbia's catastrophic breakup Feb. 1 and the recorder's long fall back to Earth. Engineers are increasingly optimistic about recovering potentially valuable data from the salvaged tape that could shed additional light on the aerodynamic forces and temperatures the shuttle experienced during its final minutes.

Columbia's OEX recorder was recovered in Texas. Photo: CAIB

"They're taking a great deal of care with it," said Bradley Allen, a spokesman for Imation Corp., a Minnesota company that specializes in data storage and recovery. "My understanding is at least visually, it came in in fairly good condition, considering what the device went through."

The so-called OEX recorder was located last week by search crews walking a grid near Hemphill, Texas. It was found slightly embedded in soft ground and while the case showed signs of damage, it appeared to be surprisingly intact.

The recorder was shipped to Imation Friday for initial inspection. Imation engineers opened the OEX recorder over the weekend and first removed unrecorded tape from the supply reel to gain experience handling the material. They then removed the recorded tape on the takeup reel and began cleaning it by hand.

The tape will be shipped to the Kennedy Space Center Tuesday, where it will be copied. Only then will engineers begin the process of playing back whatever data might be present.

Unlike the reel-to-reel recorders familiar to audiophiles, those with side-by-side takeup and supply reels, the OEX recorder features two large reels stacked on top of each other. The lower supply reel plays out tape when the machine is activated and after data is encoded, the tape is wound onto the upper takeup reel.

The OEX tape separated, or broke, between the supply and takeup reels, but engineers say the amount of tape seen on the takeup reel indicates the recorder began operating as planned roughly 15 minutes before Columbia's descent began.

Another view of the OEX recorder. Photo: CAIB

Columbia was the only shuttle equipped with an OEX recorder. Columbia was NASA's first space shuttle and as such, it was more heavily instrumented than subsequent orbiters to provide essential test flight data.

While NASA already has telemetry from Columbia that was beamed back to Earth in realtime during the shuttle's descent, the OEX recorder was designed to store data from hundreds of other sensors, providing direct measurements of temperature, vibration, dynamic pressure and other forces during launch and re-entry.

Assuming the tape holds readable data, NASA investigators hope to gain potentially crucial new insights about Columbia's final minutes. At the very least, officials say, the OEX data should help investigators validate, or confirm, the realtime telemetry already in hand, which in some cases was garbled during transmission.

The OEX recorder carried 9,400 feet of 1-inch-wide 28-track magnetic tape. The device operates at 15 inches per second - 75 feet per minute - and can hold two hours worth of data. NASA officials say the recorder was activated 15 minutes before Columbia's re-entry began, or around 8 a.m. on Feb. 1. The recorder presumably ran until vehicle breakup a few seconds past 9 a.m.

But at least some of the tape near the point where it separated between the takeup and supply reels is too damaged for any data recovery. That lost data presumably covered the very final seconds of entry just prior to breakup.