11:20 pm EST update on launch
FLORIDA TODAY Space Online
Delta/Globalstar-4 Launch Journal
From countdown through spacecraft separation this page will keep you informed with the
latest on the flight of a Boeing Delta 2 rocket carrying four Globalstar communications
satellites. These updates are prepared by Space Online's Justin Ray.
For complete stories, images and multimedia files from FLORIDA TODAY, as well as
official news releases, see our Space Today page.
Wednesday, July 7, 1999
Update for 11:20 p.m. EDT
The mobile service tower has been rolled away from the Boeing Delta 2 rocket
atop Cape Canaveral Air Station's pad 17B. The MST is used to assemble the
rocket on the pad, plus provide access and weather protection. The rocket is now
brightly illuminated by powerful floodlights as workers continue with preparations
for a planned 5:17:37 a.m. EDT launch tomorrow.
Final pre-launch work will lead to the start of terminal count at 2:17:37 a.m. EDT
at the T-minus 150 minute mark. Two built-in holds are scheduled into the
countdown - at T-minus 20 minutes for 20 minutes and at T-minus 4 minutes for
10 minutes.
The major milestone will come at about 3:30 a.m. EDT when Boeing officials will
decide which of today's two available launch windows to use. The
three-minute-long windows open at 5:17:37 and 8:17:07 a.m. EDT, respectively.
Boeing can only try for one window or the other, not both. The reason is
super-cold liquid oxygen, used by the first stage main engine, can remain onboard
the rocket for not longer than three hours. The launch team typically begins
pumping liquid oxygen aboard the Delta 2 at T-minus 75 minutes, which is actually
one-hour and 45 minutes before the launch. The two launch opportunities on
Thursday are too far apart in order to support both.
The timing of the two windows is geared toward shooting the four Globalstar
spacecraft into two open planes of the satellite constellation - one window for
each plane. In all, the constellation will feature eight planes with six operational
spacecraft in each.
The Boeing launch team is readying a Delta 2 rocket to carry another cluster of
four Globalstar communications satellites into space. Liftoff will be possible during
one of two launch windows: 5:17:37 to 5:20:37 a.m. or 8:17:07 to 8:20:07 a.m.
EDT (0917:37-0920:37 or 1217:07-1220:07 GMT). Officials will select one of
the windows prior to loading liquid oxygen aboard the rocket's first stage on
launch morning. A decision to proceed with the first window would come around
3:30 a.m. EDT.
Air Force meteorologists say there will be an 80 percent chance of acceptable
weather conditions on Thursday. The threat will be coastal rain showers in the
area. Here is an overview from Tuesday's weather forecast:
"Surface and upper level high located north of FL to continue deep
east-southeasterly flow over the next couple of days. Upper level low pressure
currently east of the Bahamas will move westward across southern FL over the
next 24-36 hours. Dry, subsiding air ahead of this low will inhibit shower and
thunderstorm activity until mid day on Thurs. Once this upper low moves west of
FL, the moisture depth will again increase as well as the coverage of showers and
thunderstorms. Main concern for launch will be a slight chance of a coastal shower
moving in the proximity of the pad.
The forecast calls for scattered clouds at 3,000 and 15,000 feet, visibility of 10
miles or better, southeasterly winds at 5 gusting to 10 knots, a temperature of 76
to 78 degrees F for the first window and 80 to 82 degrees F for the second and
humidity of 80 percent.
Should the launch be delayed for some reason, the forecast for Friday and
Saturday shows a 60 percent chance of good weather on those days.
-Justin Ray
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