IN HIS study of the Challenger explosion, journalist Malcolm McConnell exposes the seamy side of NASA's space shuttle program. His research unearthed details about the disaster that didn't appear in newspapers or the official report of the Rogers Commission. After reading McConnell's tale of the compromises and duplicities that riddled NASA's attempt to develop a reusable space vehicle, you'll be astonished that the Challenger--or any other shuttle--flew a single successful mission.

Challenger: A Major Malfunction

By Malcolm McConnell

Doubleday; 269 pages; $17.95.

The bulk of Challenger: A Major Malfunction consists of McConnell's reconstruction of the three days leading up to the doomed launch. He punctuates this narrative with flashbacks tracing the pork--barrel politicking and bureaucratic bungling that plagued the shuttle program from its inception.

Before the disaster, as McConnell tells it, NASA's public relations department was more astute than its management. Press releases boasting of a shiny, fail-safe shuttle fleet that would give the United States "routine access to space" flooded the media, which took NASA's word at face value.

But, according to McConnell, those press releases were nothing but hype. For instance, only two of NASA's four shuttles were flight-worthy at any one time. A severe parts shortage, which NASA concealed, made it necessary for each shuttle to share parts with the others. One NASA official testified before the Rogers Commission that the agency "would have been brought to its knees" by the spare parts shortage had there been no Challenger disaster.

THE STORY of the Challenger begins in the Nixon Administration, when the design of the shuttle, the most complex machine in history, was cemented. One major compromise followed another, as NASA felt the heat of budget constraints and political pressure. The space shuttle became, in McConnell's words, "a hybrid born of desperation."

Foul play surrounded NASA's contract awards from the beginning. In 1970, North American Rockwell planted one of its top executives, Dale Myers, in a key post at the space agency. In his new job, Myers had authority over the award of a $500 million contract that Rockwell wanted. Rockwell received the contract, although the company was considered to be an underdog before Myers joined the space agency.

The following year, NASA granted Rockwell a second contract, this one worth $2.6 billion. Soon after, Myers returned to a high management position at Rockwell. Today, Dale Myers has switched his loyalties again. Last September Ronald Reagan appointed him deputy administrator of NASA, the agency's number two position.

All of this wheeling and dealing, of course, had effects beyond the fortunes of one executive and his company. Engineers at McDonnell-Douglas, one of Rockwell's competitors for the orbiter contract, foresaw the precise cause of the Challenger explosion--14 years before it occurred--and devised a solution for it. But McDonnell-Douglas couldn't play the game of "government contract hardball" as well as Rockwell and didn't play a major role in the program.

McConnell also suggests that NASA's overworked employees unwittingly contributed to the disaster. They--and by extension the Challenger crew--were the victims of unrelenting stress and abominable working conditions.

For nearly a month before the Challenger launch, no important shuttle manager or technician had a single day off. Ten and fourteen-hour days were commonplace. One NASA doctor even told McConnell that heroin, cocaine and hallucinogens were "readily available" on shop floors.

But McConnell stops short of blaming NASA employees for the disaster; indeed, his book is dedicated to them. Rather, he deplores the overwhelming pressure placed on them by their superiors--in NASA and, possibly the White House--which all but forced them to make mistakes.

ABOUT HALFWAY through the book McConnell begins his excruciatingly detailed description of the three days preceding the doomed launch. Unfortunately, this blow-by-blow account of the accident is ??? engaging than the shuttle's shadowy history.