Follow the countdown and launch of the Boeing Delta 2 rocket with the U.S. Air Force's GPS 2R-8 navigation spacecraft. Reload this page for the very latest on the mission.

1350 GMT (8:50 a.m. EST)

Weather officer Joel Tumbiolo has issued his latest forecast for today's launch opportunity. He is now calling for less than a five percent chance of violating the launch weather rules during today's 14-minute window, which extends from 1:06 to 1:20 p.m. EST.

The launch time conditions are expected to include scattered clouds at 5,000 feet with 3/8ths sky coverage and tops at 8,000 feet, broken clouds at 25,000 feet with 5/8ths sky coverage and tops at 27,000 feet, visibility of 10 miles, southeasterly winds from 120 degrees at 8 gusting to 12 knots, a temperature of 68 to 70 degrees F and relative humidity of 50 percent.

1100 GMT (6:00 a.m. EST)

The mobile service tower enclosing the Boeing Delta 2 rocket at Cape Canaveral's pad 17B has been retracted for launch, setting the stage for final pre-flight preparations and fueling operations this morning.

The metal cocoon-like structure is used to assemble the Delta 2 on the seaside pad, as well as provide workers access to all reaches on the vehicle and weather protection for the rocket.

Liftoff is targeted for 1:06 p.m. EST at the opening of a 14-minute launch window.

0400 GMT (11:00 p.m. EST Tues.)

A satellite to sustain the U.S. Global Positioning System remains scheduled for launch at 1:06 p.m. EST (1806 GMT) today aboard a Boeing Delta 2 rocket from Cape Canaveral Air Force Station in Florida.

Officials held a series of final reviews Tuesday, clearing the way to begin the countdown early this morning.

"Right now there are no issues to report. Delta 2 and the spacecraft are "green" and we are ready to launch. So 'Let's Roll,'" Air Force launch director Lt. Col. Brad Broemmel said Tuesday afternoon.

The rocket's nose cone is sporting a special emblem with the words "Let's Roll" to honor the heroes aboard the commercial airliner that crashed in Pennsylvania on September 11, 2001. Authorities believe that plane was headed for Washington, but the passengers fought against the hijackers and forced the plane down before it could strike the White House or Capitol.

"This will be our special tribute to the men and women who gave their lives in defense of this country on September 11. As many of you recall, Mr. Todd Beamer said those words to his wife on his cell phone. He led the revolt on Flight 93 that represented the first counter-offensive by America on the war on terrorism. So this is of significant importance to all of us. 'Let's Roll' captures the spirit of today's military -- people who are ready, trained and they stand up and say 'send me,'" said Broemmel.

Each Air Force base was permitted to have one vehicle with the tribute artwork. This Delta 2 rocket was selected due to the GPS' continued support of troops overseas fighting the war on terror.

The mobile service tower enclosing the rocket at pad 17B is scheduled to be rolled back for launch around 4:30 a.m. EST. That is when the first clear view of the nose art will be seen.

Not only is the Delta 2 carrying the GPS 2R-8 spacecraft, an experimental micro-satellite is riding on the rocket's second stage. The XSS-10 craft will separate from the spent stage around 16 hours after liftoff and perform autonomous maneuvers around the rocket body for several hours using newly-developed guidance and control software.

"The XSS-10 is the first in a series of future micro-satellites the Air Force plans to use for inspection, rendezvous and docking and close-up maneuvering around other space objects," said Thom Davis, the program manager from the Air Force Research Laboratory.

"We are very excited to be a part of this historical launch. It represents an essential advancement in space research and technology and will pave the way for future, low-cost, on-orbit servicing and other space missions."

Be sure to watch this page for live play-by-play updates during the final hours of the countdown and the 68-minute flight of the Delta 2 rocket to deploy GPS 2R-8.

1535 GMT (10:35 a.m. EST)

The Boeing launch readiness review has been completed this morning. Officials say everything is set for the 1:06 p.m. EST liftoff Wednesday of Delta 295. An Air Force review will be held later today. The pre-launch news conference will follow at 3:30 p.m. EST.

1500 GMT (10:00 a.m. EST)

The final launch readiness reviews are being held today to confirm all systems are "go" for tomorrow's flight of the Boeing Delta 2 rocket and GPS 2R-8 spacecraft from the Cape Canaveral.

The weather forecast remains nearly ideal with less than a 10 percent chance of conditions prohibiting liftoff.

"On launch day a frontal boundary will be located over southern Georgia, with high pressure continuing to dominate central Florida with partly cloudy skies, warmer temperatures and light winds. There will be some higher levels clouds associated with the jet stream, but they are not expected to be thick layered. Thick layered clouds and cumulus clouds in the local area will be the only issues monitored during the countdown," Launch Weather Officer Joel Tumbiolo reported this morning.

The launch time conditions are expected to include scattered clouds at 5,000 feet with 3/8ths sky coverage and tops at 8,000 feet, broken clouds at 28,000 feet with 5/8ths sky coverage and tops at 30,000 feet, visibility of 10 miles, southeasterly winds from 120 degrees at 8 gusting to 12 knots, a temperature of 66 to 68 degrees F and relative humidity of 50 percent.

The forecast for Thursday and Friday calls for a 10 percent chance of bad weather both days, with thick cloud and cumulus cloud the concerns.


After its liftoff was delayed last fall by a launch pad crane incident, an Air Force Global Positioning System satellite is now ready to fly atop a Boeing Delta 2 rocket Wednesday to replace an ailing craft in the military's orbiting navigation network.

The three-stage Delta 2 will have a 14-minute window -- from 1:06 to 1:20 p.m. EST (1806-1820 GMT) -- to launch the $40 million NAVSTAR GPS 2R-8 spacecraft from Cape Canaveral Air Force Station's pad 17B.

Meteorologists are predicting less than a 10 percent chance of weather scrubbing the liftoff.

This Delta 2 rocket has been on the pad for about 10 months, originally stacked for a spring launch. But Air Force-ordered reviews of the vehicle's safety destruct system and internal wiring led to the mission's delay until November.

Then in late-October when the GPS satellite was being mounted atop the rocket in the pad's clean room, miscommunication between workers caused a mishap that damaged part of the $50 million launcher.

The extensive inspections and work to fix the rocket postponed the launch until now.

"During hoisting of the Delta 2 GPS 2R-8 third stage and spacecraft, the Boeing crane operator misinterpreted a hand signal given by the Boeing technician and raised the crane instead of lowering it. This incorrect lift direction damaged the third stage spin table, which was bolted down," the Air Force said in a written statement about the incident.

"A miscommunication between the Boeing technician and the Boeing crane operator, as well as a lack of understanding of the operation itself, led to the hoisting incident on October 25, 2002," the Air Force said investigators determined was the root cause.

The spin table for the rocket's upper stage, which literally spins during the launch sequence, took the brunt of the damage and has been replaced. Other hardware swapped out included ordnance and spin rockets on the third stage, the Air Force said.

"The base of the Delta 2 third stage spin table sustained damage, as it was the weakest structure in the load path. A replacement spin table was processed," the statement read.

"Structural, dynamic and shock analyses were completed for the second stage guidance section and third stage components. These analyses showed that the loads seen during the hoisting incident were encompassed by flight loads on all parts of the rocket except the forward end of the second stage guidance section. Visual inspections, dimensional checks and non-destructive inspections were done on the second stage guidance section. No damage was discovered during these inspections.

"The Star-48B third stage motor was returned to the vendor and thoroughly inspected. No damage was discovered during the inspections," the statement went on to say.

After the mishap, workers returned the payload to its processing facility for checks to ensure the satellite was unharmed and would operate properly once in space.

"The GPS spacecraft went through extensive visual inspections as well as analysis to demonstrate the ability of the spacecraft to handle the shock levels seen during the hoisting incident. Spacecraft tests were also conducted."

Officials say changes have been made to prevent such an incident in the future.

"Boeing has put multiple corrective actions into place," the Air Force statement said. "All Boeing crane operators, riggers, and supervisors must now undergo updated training on the operation of the crane. In addition, Boeing will conduct a pre-test briefing with all personnel prior to beginning any launch processing procedure. Applicable lessons learned will be reviewed, and the Boeing test conductor will stress proper test discipline. Boeing is also in the process of reviewing all procedures to ensure that critical handling and lifting events have discrete steps to ensure positive communication prior to crane movement."

The Lockheed Martin-built GPS 2R-8 satellite -- also known as SVN-56 -- will be deployed into the GPS constellation's Plane B, Slot 1. The new craft will replace the GPS 2A-18 satellite -- also known as SVN-22 -- launched 10 years ago next week. The aging satellite will shift positions in Plane B and retire, the Air Force said.

GPS satellites operate 10,900 miles above Earth to provide precision location, speed and timing information to military forces and civilian users around the globe.

The network encompasses 24 primary satellites divided into six orbital planes with four spacecraft in each. Some planes also have an additional satellite to serve as spares.

This will be the first GPS launch since January 30, 2001. Two more are planned in the coming months from Cape Canaveral -- one in late March and one in mid-July.


The "Let's Roll" commemorative artwork flying on the nose of the Delta 2 rocket to salute the heroes of September 11. Credit: Air Force

Pre-launch briefing
Launch timeline - Chart with times and descriptions of events to occur during the launch.

Global Positioning System - Description of the U.S. Air Force's space-based navigation network.

GPS constellation - Chart shows the current status of the orbiting GPS satellite fleet.

XSS-10 - The experimental microsatellite flying as a secondary payload on this launch.

Delta 2 rocket - Overview of the Delta 2 7925-model rocket used to launch GPS satellites.

SLC-17 - The launch complex where Delta rockets fly from Cape Canaveral.

Delta directory - See our coverage of preview Delta rocket flights.

Flight Data File
Vehicle: Delta 2 (7925-9.5)
Payload: GPS 2R-8
Launch date: Jan. 29, 2003
Launch window: 1:06-1:20 p.m. EST (1806-1820 GMT)
Launch site: SLC-17B, Cape Canaveral, Florida
Satellite broadcast: AMC 2, Transponder 4, C-band

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