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Archive for December, 2007


20-Dec-07 | Delta flight 331 – NAVSTAR IIR-18 (M5)

A Delta II 7925 today lofted another Global Positioning System replenishment satellite for the U.S. Air Force.

Liftoff was delayed by five minutes after the opening of the fourteen-minute launch window due to a collision avoidance period, or COLA, which is a common occurrence in launches since there are so many objects already in orbit. Despite the COLA, the countdown was without major issues, and the three-stage Delta II left the pad at Cape Canaveral’s SLC-17A with an official range liftoff time of 20:04:00.353 GMT.

Fifty-eight minutes later, the GPS satellite was released into its nominal transfer orbit, which is an elongated path of about 11,000 nautical miles in apogee. The satellite will fire its own onboard AKM within the next several days to circularise its orbit. It will enter Plane C, Slot 1, replacing IIA-24, which will move to Plane C, Slot 5 to replace IIA-20. (IIA-24 was launched aboard Delta 226 in 1994. IIA-20 was launched on Delta 220 in 1993, and has more than doubled its seven-year design lifetime. It is showing signs of its age and will be decommissioned.)

This was the 46th launch of a GPS satellite by Delta II, all but one of which have been successful. (A further 11 experimental GPS satellites were launched on Atlas vehicles between 1978 and 1985.) It was also the 79th consecutive successful launch for Delta II, a continuing world record.


10-Dec-07 | Delta flight 330 – COSMO-SkyMed 2

On the evening of Saturday, 08 December 2007, a two-stage Delta II Med-Lite launched the second in a constellation of Italian radar satellites known as COSMO-SkyMed. The launch from Vandenberg Air Force Base’s SLC-2W occurred at an official range liftoff time of 18:31:42.118 PST (02:31:42.118 GMT on 09 December).

At 58 minutes 4 seconds after launch, the satellite was deployed into a near-circular polar orbit. When it becomes operational, COSMO-SkyMed 2 will join its siblings in providing environmental monitoring, resource management and territorial surveillance for the Italian Space Agency and the Italian Ministry of Defence. COSMO is an acronym meaning “COnstellation of small Satellites for the Mediterranean basin Observation”, intriguingly not an Italian phrase. (No word on the meaning of SkyMed, which this author suspects is the IMoD name for the constellation.)

Delta II continued its longest-ever success record with this flight, the 78th in a row. As usual, Spaceflight Now’s Justin Ray provided an excellent play-by-play here.

Amidst the excitement of a successful deployment, it was announced that COSMO 3 will launch aboard another Delta II in the second half of 2008. The launcher for the fourth satellite in the constellation has not yet been chosen—several competitors are vying for the contract.


07-Dec-07 | Another scrub for COSMO 2

Strong winds at Vandenberg prevented pullback of the mobile service tower today. A 24-hour turnaround is in work; Saturday’s liftoff is set, as on previous days, for 6:31 p.m. PST (02:31 on 09 December GMT).


06-Dec-07 | COSMO-Skymed 2 scrubbed, delayed

Yesterday’s attempted launch of the Italian COSMO-SkyMed 2 satellite was scrubbed with less than three minutes left in the countdown, when a high-altitude weather balloon reported unacceptable upper-level winds. The Delta II vehicle was safed at SLC-2W and the launch team immediately began preparations for a 24-hour turnaround.

However, during post-scrub inspections it was found that some cork insulation had debonded and will need to be reattached. The insulation is used to protect portions of the first stage from hot gases that can impinge on the vehicle’s skin during liftoff and flight. This cork—and it is in fact real cork wood, a low-tech but suitable solution that has been used on Delta for years—has come loose on vehicles in the past, and repair is usually trivial and quick to complete.

Launch is now tentatively scheduled for Friday evening, 7 December.


     

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