According to a newly released in-house report on NASA's training program for shuttle crews, many astronauts feel their books are "out of date" and "poorly written," their equipment "terrible," their instructors "barely adequate" and the pace of training erratic.

Robert Crippen, director of the space shuttle program and a former astronaut, yesterday dismissed the report as unduly negative and reflecting the views of fewer than 10 percent of the astronauts in training. "There are things that we're tightening up," he said, but most of the findings, "when you examine them in depth, are fluff."

The "internal audit" of the astronaut training program at Johnson Space Center (JSC) in Houston was completed by NASA's inspector general last August. It included responses to confidential questionnaires given to the 93 astronauts who were training for shuttle missions during 1989. Seventy-four responded. Intended to review the quality of instruction since the Challenger disaster, the report noted many improvements but warned of five serious "potential problems":

Simulators. The JSC has only two simulator modules, with a third planned for 1992 -- "grossly inadequate," according to one astronaut. Others complained that the units frequently malfunctioned and provided poor visual effects, particularly the aft displays depicting the area of the spacecraft where critical cargo and robot arm systems are located. Comments ranged from "antique" to "garbage" and "Dark Age technology."

Training materials. Numerous astronauts criticized their manuals as outdated and poorly written. One trainee said it was "very difficult to find out the things that are really important."

Instruction. Many complained that high staff turnover left the program with too many young or inexperienced instructors. As a result, said one astronaut, "we've given up on the trainers and just 'train ourselves.' " Moreover, because of simulator shortages, much mission-critical training was delayed until the final few weeks before launch.

Payload training. A large number of astronauts said they were inadequately trained to handle "secondary payloads" -- scientific or industrial equipment carried in addition to a mission's primary cargo -- and that instruction took place "too late in the training flow."

Schedule. Many astronauts feared that training facilities and materials were too limited and problem-ridden to prepare crews for the planned shuttle flight rate. The study concluded that "budgetary actions should be taken immediately to acquire additional facilities, equipment and personnel or the shuttle mission schedule should be revised accordingly."

Crippen yesterday said that the report -- made public this week after the Orlando Sentinel obtained a copy through the Freedom of Information Act -- overemphasized criticisms of the training regimen.

For example, he said, in response to questions about the general quality of instruction, more than 70 percent of the astronauts rated the program good to excellent. "Only 8 percent had negative things to say," Crippen said, "and the report was written on those 8 percent."

Crippen acknowledged that many problems cited in the report had been known for months -- in some cases, for years. "The aft display windows have been terrible" since the first shuttle launch, "but they're workable," he said.

However, some difficulties are endemic to the program. Late training on secondary payloads occurs because cargo decisions are often delayed to provide "maximum flexibility," he said, and access to simulators is inevitably limited because "the next guys up get the prime time," Crippen said.

As for the launch schedule, he said, "some adjustments have been made since that report was done." Seven shuttle missions are planned for 1991.

Despite the number of astronauts who were critical of the program, he said, "you won't find any of them that said they weren't well trained and ready to fly when the time came. That's the bottom line."

NASA now has three operational shuttles, with a fourth in construction, and has not requested funding for more. The shuttle Columbia, Crippen said, would be out of commission for about six months later this year while it is fitted with "extended duration" gear permitting up to 16 days in orbit and a "drag chute" to aid braking during landings.

Meanwhile, NASA and the Air Force have begun joint planning for an unmanned heavy-lifter rocket that could carry payloads up to 150,000 pounds and be reconfigured to accommodate crews.

The heavy-lifter project, William Lenoir, NASA's associate administrator for space flight, said yesterday, will not only "decrease reliance on the space shuttle by the turn of the century" but "make America much more competitive in the international launch industry." Adding advanced solid-fuel rockets to the basic design, he said, "makes it a Moon- or Mars-class vehicle."

NASA also announced further revisions in the design for the embattled space station. Lenoir said the new plan calls for a simple spine or "integrated truss" to which laboratory or habitation modules can be attached, as well as for smaller modules measuring 27 feet long (down from 44 in earlier designs). That change, Lenoir said, will greatly reduce the amount of extra-vehicular activity required to fit the modules to the frame, since equipment can be mounted in the modules before launch and tested on Earth.

Also in the planning stages, Lenoir said, was a "crew-return vehicle" intended to provide "a way to get space station crews home independent of the shuttle."

Less optimistic was the prognosis for NASA's systems integration and engineering unit at Reston. Established after the Challenger explosion in an attempt to better coordinate the efforts of individual contractors, the unit's performance has been hampered, among other things, by the reluctance of NASA personnel to move to the Washington area. Some have suggested relocating the unit to JSC or Marshall Space Flight Center in Huntsville, Ala., where engineers are already plentiful.

"In the next two to four weeks," Lenoir said, the fate of the operation will be decided. "All options are under consideration, from not changing a thing to closing Reston entirely."