Series of Rocket Failures Unnerves U.S. Space Launching IndustryBy WARREN E. LEARY W ASHINGTON -- Suddenly, America's space rockets seem to be failing, blowing up or losing payloads at an alarming rate that has experts questioning the prowess of an increasingly competitive satellite launching industry. In the last nine months, there have been six significant failures of U.S. rockets trying to put civilian and military payloads into orbit. The mishaps, involving both older, usually reliable rockets and newly designed spacecraft, have resulted in losses totaling $3.5 billion and shaken confidence in the ability of the United States to launch space missions, including crucial communications and spy satellites. Engineers studying the problem say they cannot tell if the recent difficulties are just bad luck or signs of systemic problems in the launching business. A number of explanations have been floated to explain the string of disasters, ranging from an over-reliance on computer models in place of flight testing to the pressures to do more for less money. "The performance we've demonstrated since last August is unacceptable, to us and to our customers," said Peter B. Teets, the president and chief operating officer of Lockheed Martin, whose rockets are responsible for the loss of four satellites since August. "The worst impact on morale is losing a mission," Teets said. "We have good people who are not feeling very well right now.". John F. Willacker of Aerospace Corp., a private consulting and engineering research company based in El Segundo, Calif., said the nation's space launching industry was suffering from being under the competing pressures of flying more rockets at less cost while also trying to introduce new boosters that are even more economical. The satellite launching business is booming, with an unprecedented number of customers in science, communications and other industries clamoring to get their payloads into space. At the same time, there is great pressure to reduce the cost of launchings, with American companies being forced to compete with low-cost launching services being offered by Europe's Ariane rockets and boosters available in Russia and China. "The industry is a little stretched, and this pressure is contributing to some systematic problems," Willacker, head of the consulting company's space launching operations, said in an interview. "I have a hard time believing there can be this much bad luck in a row without there being some common threads," he said. "We must find them and straighten them out." Meanwhile, though, the troubles are causing apprehension for rocket users as well as flight delays while engineers sort out the problems to determine whether future missions are in danger. With some three dozen military and civilian launchings scheduled from the UnitedStates, this is a particularly busy year for the American launching industry. The Air Force has indefinitely postponed the flight of a giant Titan IV rocket, which has failed three times in its last three launchings and which was to carry a secret spy satellite into space early this month from Vandenberg Air Force Base in California. This delay, in turn, prevents the scheduled launching of an older rocket, the Titan II, from an adjacent pad. The Titan II is supposed to orbit a NASA science spacecraft called Quikscat. And NASA has pushed back the scheduled July 22 flight of the space shuttle Columbia, which is to carry the $1.5 billion Chandra X-ray Observatory into space. An attached booster rocket that is to drive the observatory into its final orbit is the same type as one that malfunctioned last month. The space agency is going ahead with plans for a July launching of Terra, a billion-dollar satellite that is the flagship of NASA's Earth Observing System to monitor global changes, even though the upper stage of its carrier rocket, a Centaur, is identical to one that misfired last month and doomed a military communications satellite. But a spokesman said NASA was monitoring the military investigation to see if it uncovered concerns that might affect the launching of the Terra. The current string of mishaps began last Aug. 12 when a Titan IV, the most powerful rocket used by the military, exploded 41 seconds after liftoff, destroying an $800 million communications intelligence satellite along with the $340 million rocket. An Air Force review board blamed damaged electrical wires that were not detected before the flight. The two other Titan IV setbacks, at a cost of about $1 billion each, occurred in April, apparently for dissimilar reasons. On April 9, an upper stage deployed from the Titan as expected, but apparently parts of it failed to separate properly between multiple firings, putting a missile warning satellite in a useless orbit. This booster, made by the Boeing Co. and called the Inertial Upper Stage, is the same type that is to propel NASA's Chandra observatory. And on April 30, a different upper stage, the Centaur, malfunctioned and put a military communications satellite in an orbit thousands of miles too low, where it is doubtful it can ever be used. The trade journal Aviation Week and Space Technology reported in its May 10 issue that the Centaur went awry nine minutes into the mission because of inaccuracies in computer flight software from the rocket's maker, the Lockheed Martin Corp. The errant software was loaded before the flight, and problems went undetected by the company's normal verification process, the report said. Botched launchings also affected civilian space missions: On Aug. 26, Boeing's new Delta III rocket exploded 71 seconds afterliftoff on its maiden voyage, destroying the Galaxy 10 communications satellite in a $225 million disaster caused by a design error in its first-stage guidance system. On April 27, the Athena II, a relatively new small rocket made by Lockheed Martin Corp., failed to place a private earth-imaging satellite into orbit after launching from Vandenberg Air Force Base in California. A 1,300-pound protective payload shroud failed to separate from the