Tom Young, a retired Lockheed Martin executive, and John Casani, retired chief engineer at the Jet Propulsion Laboratory, told the House panel that too little money and too few people forced NASA to cut corners on the failed Mars Climate Orbiter and Mars Polar Lander missions.
Young and Casani each led an independent study that examined the reasons behind the failures.
But lawmakers said the two studies show that NASA’s mistakes could not be fixed simply with money.
"I am a little disturbed how quickly people conclude that hiring and money will solve all our problems," said Rep. Dana Rohrabacher (R-California). "It seems to me that that’s an easy way out."
Although the lawmakers thanked Young and Casani for their work, their reaction to the two studies showed that Congress remains reluctant to boost NASA's budget.
NASA hopes Congress will support the agency’s $14 billion budget request this year, a 3.2 percent increase over what NASA got last year.
The two studies found that the Mars Polar Lander failed due to a software glitch that accidentally shut off the craft’s engines, causing it to plummet to its death on Mars on December 3, 1999.
The Climate Orbiter crashed into the planet or broke up in its atmosphere in September after a failure by spacecraft builder Lockheed Martin to convert English measurements to metric in calculating its trajectory.
Together, the missions cost about $290 million.
In both cases, Young said project managers cut corners. They got rid of such basic processes as having someone double-check another’s work, conducting verification tests or raising red flags when problems arose.
Casani testified that the orbiter’s project managers noticed a problem in the craft’s trajectory months before its crash. But the team communicated informally through e-mails instead of sounding any alarms that, Casani said, could have saved the craft.
Young said problems ultimately arose because both Lockheed Martin and the Jet Propulsion Laboratory, which operated the missions, were strapped for resources.
"We went too far for trying to do too much without adequate resources," Young said. "There wasn’t enough margin in terms of money, and there wasn’t enough margin in terms of weight," he said, referring to the lander’s design flaw.
Yet Rep. Vernon Ehlers (R-Michigan) and others pointed to the English-metric mix-up as the sort of mistake made in a high school science class.
"How is cutting too much [money] possibly the culprit there?" asked Rep. Mark Green (R-Wisconsin).
Sensenbrenner said he intended to bring NASA Administrator Dan Goldin before his committee to answer such questions next month.
"At its best, the American deep-space program is an inspiration to the world," he said. "Right now, I’m sorry to say, it’s starting to lose its luster."