Military Weather Satellite Rockets Into Polar Orbit

by Justin Ray

Date: 05 November 2006 Time: 12:18 PM ET

A globe-spanning weather observatory successfully launched into space Saturday aboard a Boeing Delta 4 rocket, giving the U.S. military a new set of orbiting eyes to help plan air, sea and land operations around the world.

With the first hint of daybreak on the horizon at California's Vandenberg Air Force Base, the Delta 4's hydrogen-fueled RS-68 main engine ignited with its dramatic but normal fireball racing up the vehicle's side. At 5:53 a.m. local time (8:53 a.m. EST; 1353 GMT), the $75 million booster was unleashed to begin the 18-minute ascent to deliver the weather satellite to space.

The 20-story rocket left a red-hot trail of flame a couple hundred feet long as it slowly climbed away from Space Launch Complex 6 -- a pad once built for West Coast space shuttle flights.

The first stage completed its firing about four minutes into flight, then jettisoned to allow the cryogenic second stage to light its RL10 engine to complete the job of lofting the 2,700-pound payload. The satellite was deployed 18 minutes after liftoff.

The Defense Meteorological Satellite Program F17 spacecraft flew into a perch more than 450 nautical miles above Earth, looping from pole to pole to cover virtually the entire planet twice daily.

"This launch is critical to the warfighter," said Lt. Col. Steve Behrens, 30th Launch Group technical director at Vandenberg. "These are our brothers and sisters, our family members and the people we go to church with, so we're going to do this right. This is really important to the nation."

The $370 million craft should enter service next month to provide visible and infrared imagery of clouds, day or night, plus measure winds, soil moisture, ice and snow coverage, pollution, fires and even spot dust storms in Iraq.

"The primary sensor ... provides basically pictures of the clouds in both the infrared and visible spectrum," said Col. Brad Smith, DMSP group commander at the Space and Missile Systems Center. "DMSP...is the only satellite that can pick up clouds at night by moonlight, so it has that degree of sensitivity."

Six data-receiving terminals are located in today's major military theaters, enabling weather information to be downlinked directly from the satellites to commanders on the ground.

"We provide those real-time to terminals that the tactical commanders can look at, so that really helps when you're doing real-time planning."

The venerable military satellite program also aids extended weather outlooks.

"A large portion of the data that's used for long-term weather prediction, say three to five days out, comes from these polar-orbiting satellites," Smith said.

In addition, the Lockheed Martin-built satellite carries space environment sensors to warn of solar storms that can interfere with high-frequency communications, over-the horizon radars and Global Positioning System navigation.

The DMSP system flies satellites in two separate orbits, with a primary craft and a backup in each. The new F17 satellite was placed into the so-called "early morning orbit" to replace the F13 craft nearing its 12th birthday.

Launched in March 1995 aboard an Atlas E booster from Vandenberg, F13 had a three-year design life just like other DMSP satellites. But the remarkable longevity is "an anomaly" and not the norm, Smith said.

"F13 is our longest-lived satellite by far. The design life of all DMSP satellites is three years with a goal of up to four years," he said. "We've been very fortunate that F13 has lasted as long as it has. We feel that's a very good thing."

The aging satellite will become the backup in that orbit once F17 becomes operational.

Keeping F13 in good health while waiting for F17 to launch has been important for the DMSP system. Losing one of the two orbits would have meant an impact to tactical planners needing weather data.

"We are the only ones that fly in that early-morning orbit, so there are certain areas that you would not have the same currency of data," Smith explained.

The so-called "mid-morning orbit" is populated by the F15 and F16 satellites launched in 1999 and 2003, respectively.

Saturday marked the first time a DMSP satellite has flown aboard the nation's Evolved Expendable Launch Vehicle family of rockets. The three most-recent DMSPs flew atop converted Titan 2 missiles, which needed an added kick motor on the satellites to reach a safe altitude above Earth. But the next-generation Delta 4 had plenty of power to insert F17 directly into its polar orbit.

"The Delta team is proud to contribute to this important capability for national defense with this first launch of a DMSP satellite aboard a Delta rocket," said Dan Collins, vice president of Boeing Launch Systems.

"With this second successful launch of a Delta 4 from the West Coast this year, and the third Delta 4 mission in 2006, we are seeing this new launch vehicle family being put through its paces and building a record of reliability," Collins added. "I'm very pleased with the vehicle performance and the dedication to mission success demonstrated by the Delta team."

All three Delta 4s this year launched on their first countdown attempt, including the debut West Coast mission from the rebuilt Space Launch Complex 6 pad in June. And the DMSP flight stuck to its launch date set months ago.

"We planned with some margin so we were never too worried about making 4 November but I think it was an excellent job by the team of executing and getting us where we are today," Col. James Planeaux, the Air Force Space and Missile Systems Center's Delta 4 program manager, said at the pre-launch news conference Friday.

The next Delta 4 is expected in the spring from Cape Canaveral carrying a Defense Support Program missile warning satellite. Vandenberg's next Delta 4 will launch a classified National Reconnaissance Office spy satellite payload in late summer of 2008.

Three more DMSP satellites in this series are left to launch, with F18 planned for liftoff in the spring of 2008 aboard a Lockheed Martin Atlas 5 rocket from Vandenberg.