Shuttle Disaster Could Have Been Avoided

Regarding Chapter One of “Decoding Columbia: A Detective Story” (Dec. 21): Fascinating feature. I was troubled by the statement that “shuttle engineers could not stop ... chunks of insulating foam from falling off the ... external fuel tank.” Inherently, that’s a misleading statement. The purpose of the foam was to provide thermal insulation for the tank. Expendable launch vehicles also often use insulation on external surfaces, especially on the payload shrouds, which encounter similar ascent conditions. And the Department of Defense has flown reentry packages in past years that encountered similar environments.

Furthermore, since the foam did not fall off most areas, that indicates a workmanship problem that could easily have been resolved. The question is why -- why the shuttle program went on for so many years without properly addressing so obvious a deficiency. A small team of dedicated materials and process engineers could have solved the problem in a few months. In fact, they probably would have started by evaluating the lightweight insulation materials being used successfully on other vehicles that are launched into space.

George Epstein

Los Angeles