The Delta 4 rocket stands at pad 37B awaiting fueling operations during Thursday's practice countdown. Photo: Boeing/Carleton Bailie

With a countdown dress rehearsal successfully completed, Boeing's Delta 4 launch team is preparing to mount an Air Force communications satellite cargo atop the rocket next week for the planned early February liftoff from Cape Canaveral.

The second flight of the next-generation launcher is scheduled for the evening of February 6.

It will be the first military launch for the Air Force's Evolved Expendable Launch Vehicle program. EELV is the effort that led to the development of Delta 4 and Lockheed Martin's Atlas 5 boosters to reduce launch costs and improve reliability for America's rocket fleet.

In the run-up to the mission, engineers performed a practice countdown Thursday to simulate launch day activities. After the two-stage rocket was loaded with super-cold liquid hydrogen and liquid oxygen propellants, clocks counted down the final moments before the mock liftoff time. The rocket was later drained of its fuel and safed.

"It was a very good test. We satisfied all of our criteria," Delta 4 Launch Director Joy Bryant said in an interview this morning. "Our criteria was to have a clean Minus Count and do the (turbine pump assembly) spin up."

On Monday, the Defense Satellite Communications System A3 spacecraft is scheduled to be transported from a government processing building at the Cape to launch pad 37B. Workers will hoist the Lockheed Martin-built satellite, which is already encapsulated in the rocket's nose cone, into the service tower and attach it to the Delta 4 upper stage.

The following days will be spent conducting final tests on the rocket and satellite, installing batteries, working on the ordnance systems, loading hypergolics and preparing the launch complex for the blastoff.

It's a full plate for workers.

"We have a very full schedule. So there isn't room for as much flexibility," Bryant said. "But I'm pretty comfortable with it."

The Air Force-controlled Eastern Range has allotted February 6, 7 and 8 for Delta 4 launch opportunities before the vast network closes on the 10th for a planned upgrade period that officials say will last until the start of March.

The DSCS mission will use a Delta 4-Medium configuration with no solid rocket motors. Photo: Boeing/Carleton Bailie

Despite being only the second Delta 4 mission, the schedule to launch the rocket in early February has remained on track. The vehicle was rolled to the pad in mid-December.

"The guys have done an excellent job turning the experiences and lessons learned from first flight into a very smooth flow," Bryant said.

"Fundamentally, it is just learning the rocket, learning the ground systems. When you launch repetitively, it just gets much smoother as you can quickly turn around those lessons learned."

One hitch that did arise was a four-day delay to make room for the Titan 4 launch on the Range schedule after that rocket flight was postponed. The Air Force is the customer on both the Titan 4 and Delta 4 missions.

In parallel to preparations for this launch, engineers have been exhaustively examining all of the data gathered during last November's successful inaugural Delta 4 flight.

"We are culminating that data review this weekend. The design team out of California will be meeting with the customer base, reviewing and validating all of the first flight data," Bryant said, adding that there didn't appear to be any major surprises in the post-flight review.

Boeing expects a few more Delta 4 missions in 2003 -- a year that promises to be busy for the company's crews at the Cape and Vandenberg Air Force Base in California.

"It looks like it is going to be a fairly busy year for us. We've got on the order of a dozen or so launches on the manifest right now, a combination of Delta 2 and Delta 4. We are looking forward to a busy year and the team is ready to go," Jay Witzling, Boeing vice president and Delta deputy program manager, said in a recent interview.

The year began successfully on January 12 with the launch of two NASA satellites aboard a Delta 2 from Vandenberg.

At the Cape's launch pad 17B, a Delta 2 is being readied for liftoff next Wednesday to place the Air Force's Global Positioning System 2R-8 navigation satellite into orbit.