Return of the workhorse
BY JUSTIN RAY
Posted: February 12, 2014
A quarter-century since its first launch Friday, preparations are underway to end a mini-hiatus and return to the business of launching Delta 2 rockets, if only for a little while longer.
But there's been a gap for the past two years with no flights.
The matching of ready payloads with the rocket meant no launches until this summer when the start of the final sendoff to the Delta 2 begins.
There's pieces and parts to build just five more Delta 2 rockets and four of them have been sold to NASA.
First up is OCO 2, the replacement Orbiting Carbon Observatory to launch July 1 from Vandenberg Air Force Base in California, exactly 32 months since the most recent Delta 2.
A soil monitoring satellite follows in November, then a weather spacecraft in November 2016 and an ice observing craft in March 2017, all launching from California.
Attention is turning to this summer's mission, the hardware is rolling off the factory line and soon the stacking at launch pad will start.
For a time, it appeared the Delta 2 would fade into history after carrying a climate and weather observatory into orbit for NASA in October 2011.
After the U.S. Air Force transitioned its launches of new Global Positioning System satellites to the Delta 4 and Atlas 5 rockets, the Delta 2 lost its anchor customer.
But NASA breathed new life into the rocket two summers ago, purchasing four future flights from an inventory of five remaining Delta 2s.
NASA has used the Delta 2 rocket on 50 launches to date, most notably to send the Spirit and Opportunity rovers, the Odyssey orbiter and Phoenix lander to Mars, plus the Stardust and Genesis sample-return spacecraft, MESSENGER to orbit Mercury and the Spitzer infrared space telescope.
"Delta 2 production restart efforts have gone amazingly well and we're very pleased with that," said Tim Dunn, the NASA launch director for OCO 2.
Erection of the first stage at the Space Launch Complex 2-West pad is slated for March 25, followed by the solids and then the second stage on April 3. Initial on-pad power-on testing begins April 24. A countdown dress rehearsal will be held on May 21. The final systems-level test of the rocket alone is planned for June 3.
"I have been amazed at the retention of the appropriate skills and personnel ULA has kept. They have done a wonderful job with personnel to keep Delta 2 viable," Dunn said.
OCO ships out of its Orbital Sciences factory in Arizona on April 28 and goes to the Astrotech processing facility at Vandenberg for a month of final processing. It then moves to the launch pad to join the Delta 2 on June 13.
The integrated test between the payload and rocket follows on June 17, leading into the fairing installation on June 20.
Launch is scheduled for July 1 at 2:56:44 a.m. PDT at the opening of a 30-second window.
"It's exciting, as you can imagine. The entire team is very energized to get back into Delta 2 work," Dunn said. "The ULA team, everyone has been coming forward, raising hands, from the Denver design center to Decatur production to the launch site, 'I really want to work that hardware.' There's just an electricity among the greater Delta 2 team to get back into launching this vehicle."
The SLC 2-West pad was placed in quasi-caretaker status for a while before going back into normal cycles of maintenance a year before launch. Dunn said all systems are go.
The Orbiting Carbon Observatory 2 becomes NASA's environmental satellite dedicated to mapping atmospheric carbon dioxide and man's impact on Earth.
The Delta will insert the observatory into a 438-mile polar orbit to collect about 8 million measurements every 16 days to create maps showing global distribution of carbon dioxide.
Then comes JPSS 1, the first civilian weather observatory in the Joint Polar Satellite System launching in November 2016. The craft will be operated by NOAA in a 512-mile-high orbit to take the planet's pulse daily for global forecasting, providing the ingredients needed for long-term weather outlooks.
And the last currently-scheduled Delta 2 carries ICESat 2 in March 2017 to continue work begun by the program's original spacecraft, which has since been retired after a seven-year mission that monitored the melting Arctic polar ice cap. A Delta 2 launched ICESat 1 in 2003.
The Delta 2 will put ICESat 2 into a 373-mile polar orbit where the craft's multi-beam micropulse laser altimeter will provide precise global ice topography measurements of polar ice sheets and glaciers, study ice thickness and examine sea surface and vegetation heights.
There is one final Delta 2 still up for grabs.