Kevin Forsyth Home

 

History of the Delta Launch Vehicle



Current Delta News

(What about Delta IV?)

Archive for October, 2007


17-Oct-07 | Delta flight 328 – NAVSTAR IIR-17 (M4)

A three-stage Delta II rocket successfully sent a new Global Positioning System satellite into orbit today for the U.S. Air Force. The launch continued Delta II’s unprecedented string of successes, now numbering 77 in a row.

Terminal Countdown, which starts at T-minus 150 minutes, got underway today at 05:23 EDT—two hours before sunrise at Cape Canaveral—and proceeded like a finely-tuned watch. Weather conditions were thought to have a 40% chance of violating launch criteria, with the possibility of scattered rain in the area. As the countdown progressed, a 10-knot wind from the east caused the boil-off exhaust of the liquid oxygen tank to form a lengthy, horizontal plume. However by launch time upper level winds were seen to be within limits, the temperature was around 78°F, and the blue morning sky with a few scattered clouds offered smooth sailing.

The Delta II 7925 lifted off from SLC-17A at an official range liftoff time of 08:23:00.258 EDT, right at the opening of today’s 15-minute launch window. First stage flight occurred nominally, followed by a pair of second stage burns separated by a 52-minute coast phase.

Telemetry from the launch vehicle cut out after third stage spin-up and separation from the second stage, leaving flight controllers in the dark during the third stage burn and spacecraft separation, which were expected to be completed just over 68 minutes into the flight. It took another fourteen minutes or so for the Air Force to announce that it had established contact with the spacecraft and that all events had transpired normally. Delta II placed the satellite into an elliptical transfer orbit, the standard for GPS launches. Within the next few days the spacecraft is expected to fire its onboard AKM to place itself into operational orbit.

NAVSTAR IIR-17 is the 45th GPS satellite to be launched by Delta II, and is the fourth of eight “modernized” IIR satellites that provide an added signal for civilian use and two new encrypted signals for military use. It will enter the Plane F, Slot 2 position to replace IIA-14, which was launched aboard Delta 211 on 7 July 1992 (and which has far exceeded its seven-year design life). Another NAVSTAR launch is expected before the end of the year.

United Launch Alliance provided a good quality live video stream of the launch, but about ten minutes before liftoff the feed turned into loud static for about fifteen seconds. When it returned, the picture was fine, but all the audio sounded like it was being fed through a kazoo. -ed.


     

Archives

Back to top