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To Reach the High Frontier: A History of U.S. Launch Vehicles
"A valuable contribution to the field of aerospace literature," this book includes an extensive overview of Delta history and development along with chapters on Atlas, Titan, Scout, Space Shuttle, and much more.
Many other excellent books about spaceflight are recommended here.
History of the Delta Launch Vehicle
Current Delta News
(What about Delta IV?)
09-Nov-10 | Delta flight 350 – COSMO-SkyMed 4
The 93rd consecutive success for Delta II has completed a radar-imaging constellation for the Italian military and government.
The launch of COSMO-SkyMed 4, from Vandenberg AFB on Friday evening local time (02:20 UTC on 6 November 2010), went off without issue after three previous attempts were scrubbed, two for main engine compartment heating systems, one for a low voltage reading in the second stage battery. As usual, Justin Ray provided a complete play-by-play in Spaceflight Now’s Mission Status Center.
This was the only Delta II launch for 2010, and the final scheduled commercial flight for the venerable rocket. Three flights for NASA are slated for 2011, and five vehicles remain unassigned. Boeing hopes to find commercial customers for those remaining rockets.
02-Nov-10 | Third scrub
With less than a minute remaining in the countdown of Delta 350, a hold was called due to a second stage battery voltage alarm. Since COSMO-SkyMed 4 requires an instantaneous launch window to reach its precise orbit, the hold resulted in a scrub for this third attempt to launch. The launch team will take a day of rest before making another attempt on Thursday evening. [UPDATE: the attempt was rescheduled to Friday when analysis determined that Thursday’s launch window would not provide optimal placement into the constellation.]
02-Nov-10 | Second scrub
A second shot at launching Italy’s COSMO-SkyMed 4 was scrubbed last night with about 2 minutes left in the countdown. Engineers noted insufficient flow in a gaseous nitrogen purge system in the vehicle’s main engine section, meant to “ensure that critical components in close proximity to cryogenic propulsion systems are kept warm,” according to a ULA press release. No word on whether this is related to the heater issue that scrubbed the previous night’s launch. A third attempt is scheduled for Tuesday evening, November 2 (local time).
31-Oct-10 | Launch scrubbed
A Halloween-evening launch—the only scheduled Delta II flight of 2010—has been scrubbed. An unspecified technical issue brought a halt to proceedings about 25 minutes before the instantaneous launch window, set for 02:20:07 UTC on November 1. [UPDATE, 1 Nov 16:45 CDT] A heater meant to keep the engine section warm during fueling failed to operate. A second attempt will be made this evening.
The White House’s FY2011 budget, much in the news this week for having forced NASA to abandon its Constellation program and a planned return to the Moon, has implications for our ongoing understanding of climate change that are at least as significant as those for human spaceflight. More
14-Dec-09 | Delta flight 347 – WISE
Today marked the start of a new era in astronomy as NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft took flight and was successfully placed into its polar orbit by the venerable Delta II launch vehicle.
At 06:09:33 Pacific Standard Time (14:09:33 UTC), Space Launch Complex 2-West at Vandenberg Air Force Base lit up with the fire and thunder of WISE’s Delta 7320-10C Med-Lite vehicle. With only two stages and three strap-on booster motors, the 7320 has the least total impulse of any of the Delta II vehicles; nevertheless it had plenty of oomph for WISE, a lightweight craft that weighed less than three-quarters of a ton—1,457 pounds—at liftoff.
This marked the 92nd consecutive success for Delta II, an exemplary record dating back over a dozen years. In addition, the United Launch Alliance has now tallied 37 consecutive successes—one hundred percent—in its 36 months of existence. (Delta II accounts for 21 of them.)
The Wide-field Infrared Survey Explorer will survey the entire celestial sphere at least once during its nine-month mission. It is a follow-on to IRAS and COBE, two infrared surveyors that each launched aboard Delta vehicles—Delta 166 (25-Jan-83) and Delta 189 (18-Nov-89), respectively. The sensor package aboard WISE has a sensitivity at least a thousand times greater than those of its predecessors, made possible by a cryostatic system that uses solid hydrogen to keep cool. The hydrogen, weighing 35 pounds at liftoff, will gradually heat and boil away into the near-vacuum of space; hence the short mission duration.
WISE is part of NASA’s Explorer program, a series of scientific spacecraft that is older than the agency itself. More than three dozen Explorer missions have been lofted by Delta rockets, several of them still active—among them XTE, ACE, WMAP, and Swift. However with the Delta II production line shut down, and only five launch vehicles left unassigned, it is very possible that today’s launch will be the last teaming of Explorer and Delta.
10-Dec-09 | Launch delayed (update for 11-Dec-09)
The next launch of a Delta II rocket, carrying NASA’s WISE infrared surveyor, has been postponed by three days. During final checkout on 9 December, one of the vehicle’s main-stage vernier engines was found to have excessive resistance to movement. A suspect component will be swapped out. The twin vernier engines flank the Delta II main engine and provide the primary roll control (as well as some pitch and yaw control) during the first stage of flight.
Liftoff is now scheduled for Monday, 14 December, at 14:09 UTC (06:09 local time at Vandenberg’s Space Launch Complex 2-West).
29-Oct-09 | Delta flight 345 – Worldview-2
On Thursday, October 8, a two-stage Delta 2 rocket placed a commercial Earth-sensing satellite into orbit for DigitalGlobe of Longmont, Colorado.
Spaceflight Now carried extensive coverage of the launch in its Mission Status Center.
Just 11 days later, Worldview-2 snapped its first images—spectacular views of Dallas and San Antonio, Texas. Even before it has completed its calibration phase, the results are impressive.
This marked the 91st consecutive successful launch for Delta II, a record spanning more than a dozen years. Five launches remain on the schedule, with another five vehicles awaiting assignment.
28-Sep-09 | Next launch
The next Delta II launch will be Worldview-2, a commercial Earth-imaging satellite owned by DigitalGlobe of Longmont, Colorado. The launch from SLC-2W at Vandenberg is set for 8 October, a two-day delay caused by postponements in the launch of Delta 344. Worldview-2’s predecessors, QuickBird-2 and Worldview-1, each launched aboard Delta II vehicles.
25-Sep-09 | Delta flight 344 – STSS Demo
The second launch of the year by Delta II for the Department of Defense’s Missile Defense Agency has completed successfully.
Liftoff from Cape Canaveral’s SLC-17B occurred on Friday, 25 September, at an official range time of 08:20:00.223 EDT. The 65° flight azimuth took the Delta II vehicle over Europe for the first time since Mars Odyssey in 2001 (Delta 284).
This mission deployed a pair of remote sensing satellites that will demonstrate the space-based component of “a layered Ballistic Missile Defense System (BMDS) designed for the overall mission of detection, tracking, and interception of ballistic missiles.” Both satellites were deployed less than an hour after liftoff while in range of the Diego Garcia tracking station in the Indian Ocean, into circular orbits about 729 nautical miles in altitude.
Launch was scrubbed on two previous days for weather conditions. The delay has impacted on the next Delta II flight, Worldview-2, which was previously slated for 6 October from Vandenberg AFB but has not yet been rescheduled.
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