TCS Daily


Delta Force

By Sallie Baliunas - June 16, 2004 12:00 AM

The Reagan presidency saw a tremendous evolution in the United States' presence in space following the destruction of the Challenger space shuttle. More expendable vehicles for launching payloads were pursued, reviving the highly successful Delta series of rockets that had verged on extinction.

In July 1982, the Reagan administration had issued a national space policy directive re-emphasizing commitment to the Space Transportation System, encompassing the Space Shuttles and their infrastructure. The shuttles, according to the directive, would continue as the "primary space launch system for both United States national security and civil government missions," as had been policy since 1971. Expendable launch vehicles could still be built and used, because a Shuttle might not always be the optimal launch choice for all payloads, but emphasis fell on Shuttles.

As it was, production of the most powerful expendable launch vehicle, Saturn V, had ended in 1968, before men even strode the moon, and well before the Apollo 16 mission on Dec. 19, 1972, brought back to Earth the last of the 12 men ever to tread on the moon's rocks, rills and regolith. In 1984 production of the unmanned Delta ceased in anticipation of the manned Shuttle's carrying most payloads to space.

The Space Transportation System was the answer developed by the National Aeronautics and Space Administration when support and funding for human space exploration was precipitously cut after the accomplishment of John F. Kennedy's goal of putting a man on the moon within a decade.

Designed as a reusable, human-piloted, orbiting main cabin, including even the large solid rocket boosters that could be recovered, refurbished and reused, the Shuttle was expected to lower the cost of sending humans and payloads to space. Humans aboard would pilot, navigate, conduct experiments, become test subjects for living in space environment, and build an orbital space station, Space Station Freedom, finally approved in concept by President Reagan in 1984. Eventually, the system would be the platform for building a lunar science station, leading ultimately to missions to Mars, the asteroids and Jupiter. In short, the Shuttle was meant for humans to interact with space in consequential ways.

But the Space Transportation System cost much more and flew far fewer missions than planned. The dream of humans fast leaping to space dragged to a slow walk and then halted for three years on Jan. 28, 1986, when the Space Shuttle Challenger exploded shortly after launch, killing all seven crew members. President Reagan issued a ban on most commercial and non-U.S. payloads flown on Shuttles.

Yet the demand for scientific, national security and commercial space instrumentation had increased. With the Space Transportation System grounded, the lifting of those payloads was left to expendable vehicles like the Delta rockets.

Development of the Delta series was first spurred by the successful launch of the Soviet Sputnik satellite on Oct. 4, 1957. The Delta was a conversion of the U.S. Air Force's Thor intermediate-range ballistic missile, and an early Delta lofted the Echo IA satellite into orbit on Aug. 12, 1960. Subsequent Deltas evolved to become capable of delivering larger and heavier payloads to space.

But while the Space Transportation System was grounded, one of the few remaining Delta rockets failed, as did a Titan and Atlas Centaur. Facing competition from Japanese and European launchers, and with a slow permitting process holding back private rocket launches that Reagan had allowed in a 1983 directive, the administration decided to resume Delta production, ordering approximately 20 upgraded Deltas. And on Feb. 14, 1989, the U.S. Air Force launched the first components of the Navistar Global Positioning System (GPS) aboard the new Delta II.

That same year, the Shuttles were reapproved as space worthy. But the government had learned a lesson: to maintain an impressive space exploration program requires both human and non-human-tended vehicles.

After 300 launches -- from the historic Telstar to the modern GPS, and many weather and science payloads -- the Delta series should reach another milestone this July, when the new Delta IV-Heavy is scheduled for launch. The Delta IV-Heavy is powered by the first new large U.S. engine design in 25 years, since the Space Shuttle Main Engine, and is meant to drop launch costs by at least one-fourth. It represents the continual drive outward in the human age of space flight. But it also reflects another legacy of the wisdom and optimism of Ronald Reagan, even during the dark period after the Challenger disaster.


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