Delta IV Heavy Rocket to Cross Paths with Space Shuttle

This story was updated at 6:35 p.m. EST.

The U.S. Air Force plansthe first operational use of a new rocket Nov. 8, when it launches the last ofthe current generation of U.S. missile warning satellites aboard the largestversion of the Delta 4 Evolved Expendable Launch Vehicle.

The Defense Support Program (DSP)-23 spacecraft currently is targeted for launch at Cape Canaveral, Fla., on Nov. 8, according to Lt. Col. Joe Coniglio, the Air Force's DSP program manager. The space shuttle is due to return to Earth on Nov. 7, and Coniglio said during a Nov. 1 interview that the priority given to the manned mission could cause the launch of the missile warning satellite to slip by a day or two.

According to the Cape Canaveral Air Force Station, the Delta 4 launch could occur on Nov. 10.

The DSP satellite, whichwas built by Northrop Grumman Space Technology of Redondo Beach, Calif., willride on the heavy-lift variant of the Delta 4 rocket built by United LaunchAlliance. That rocket had failedto put its payload in the right orbit during a demonstration launch in December2004 when an errant sensor reading caused its engines to shut down early,contributing to more than two years of delay in the launch of DSP-23.

Coniglio saidinvestigative work conducted following the demonstration has thoroughlyaddressed the issues that led to the problems, and that he is confident in theDelta 4 heavy's ability to launch DSP-23.

In one case of pastlaunch difficulty, DSP-19 was put in the wrong orbit following its launch inApril 1999, according to Peggy Paul, Northrop Grumman's DSP program manager.While the Air Force was not able to use it for missile warning, the satellite'stwice-daily orbits through the Van Allen belt yielded valuable data forscientific and parts reliability purposes, she said.

Coniglio declined to commenton the impact to the Pentagon's missile warning capability if DSP-23 were tobe lost in a launch mishap or fail on orbit. However, he noted that the DSPconstellation is healthy, and that the satellites have far outlived theirdesign life.

Northrop Grumman has beenable to help extend the life of the satellites through adding additional fuel,improving the efficiency of fuel and battery consumption, and determiningprecisely when the satellites need to be boosted in super-synchronous orbit,Paul said.

Coniglio noted that theDSP has launched on several iterations of the Titanrocket over its 37-year history, as well as aboard the space shuttle. Inthe case of Titan 4A and Titan 4B, DSP was the inaugural payloads on thoserockets, as is the case with the Delta 4 heavy, he said.

In addition to their primaryrole of scanning the Earth to watch for ICBM launches, the DSP satellites haveplayed a role in tactical operations beginning with the Persian Gulf War in1990.

Data from the satelliteshas been used to provide warning of smaller rockets like the Scuds launchedagainst U.S. troops in the Middle East through upgrades to ground processingsystems, Coniglio said.

In addition to theirprimary infrared sensor, the DSP satellites also host a sensor suite designedto detect nuclear blasts. DSP-23 carries this sensor package, as well as anexperiment called the Space and Atmospheric Burst Reporting System (SABRS)Validation Experiment (SAVE), which is intended to demonstrate new technologyfor future nuclear detection payloads that could enable capabilities likesmaller sensor suites, Coniglio said.

Coniglio said he wasgrateful that, with satellite work winding down and the last DSP launch delayedby more than two years, key industry staff did not retire or choose to moveonto other positions. He said that kind of commitment and dedication on thepart of military, Aerospace Corp. and Northrop Grumman personnel throughout theprogram's history have been a big key to its success.

Even after the launch,the program will continue to need staff for operational support, he said.

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