Spaceflight Now: Breaking News


December 4, 1999 -- Follow the launch of seven ORBCOMM satellites aboard an Orbtial Sciences Pegasus rocket. Updates are posted approximately two minutes after the event. Reload this page for the very latest on the mission.

2015 GMT (3:15 p.m. EST)

Seven new ORBCOMM communications satellites were successfully placed into low-Earth orbit today following launch aboard an Orbital Sciences Pegasus rocket. The launch marked the 14th consecutive success for the air-launched Pegasus over the past three years.

See our photo gallery for images from the launch.

ORBCOMM's constellation of satellites in space has grown to 35 with today's mission. The network is used for two-way messaging and data transfer for customers around the world.

The spacecraft, which were placed into an orbit about 510 miles miles high, inclined 45 degrees to the equator, will undergo testing that could last three months.

This will conclude our Mission Status Center coverage of the fourth ORBCOMM deployment mission by Pegasus.

1908 GMT (2:08 p.m. EST)

T+plus 14 minutes. The HAPS stage is in a long coast period before it reignites and deploys the ORBCOMM satellites. Restart of HAPS is expected at T+plus 50 minutes, 41 seconds, beginning a two-minute 20-second firing. Spacecraft separation will occur over an hour into flight.

Public affairs commentary from the launch site has now concluded. As such, we will now pause our coverage. We will post additional information following spacecraft separation.

1905 GMT (2:05 p.m. EST)

T+plus 11 minutes, 30 seconds. As expected, communications from the rocket has ended as the HAPS stage passed out of range of the Antigua tracking station in the Atlantic Ocean. Communications will be reestablished through Canarvon at T+plus 50 minutes, 21 seconds.

1905 GMT (2:05 p.m. EST)

T+plus 11 minutes. The liquid-fueled HAPS upper stage has completed its first of two planned firings to place the seven ORBCOMM satellites into low-Earth orbit.

1904 GMT (2:04 p.m. EST)

T+plus 10 minutes. Separation between third stage and the HAPS stage has occurred. Velocity is 24,000 feet per second.

1903 GMT (2:03 p.m. EST)

T+plus 9 minutes. The third stage has burned out. Standing by for the stage to separate from the HAPS upper stage in about 45 seconds.

1902 GMT (2:02 p.m. EST)

T+plus 8 minutes. Third stage ignition confirmed.

1901 GMT (2:01 p.m. EST)

T+plus 7 minutes. Coming up on separation of the second stage in about 27 seconds. The third stage will ignite at about T+plus 7 minutes, 38 seconds.

1859 GMT (1:59 p.m. EST)

T+plus 5 minutes. Range Safety officials have given the go for third stage ignition. Altitude is approximately 340 km.

1858 GMT (1:58 p.m. EST)

T+plus 4 minutes. Altitude reported normal. Vehicle is currently coasting toward a point where the second stage will be jettisoned and the third stage will ignite.

1857 GMT (1:57 p.m. EST)

T+plus 3 minutes. The Pegasus rocket's second stage has burned out. Stage will separate in about 4 1/2 minutes.

1856 GMT (1:56 p.m. EST)

T+plus 2 minutes. Second stage has ignited and payload fairing separation confirmed.

1855 GMT (1:55 p.m. EST)

T+plus 90 seconds. First stage has burned out and separated.

1855 GMT (1:55 p.m. EST)

T+plus 1 minute. Velocity reported nominal. All systems reported go.

1854 GMT (1:54 p.m. EST)

IGNITION. The first stage has ignited. Pegasus begins its fourth deployment mission for the ORBCOMM constellation.

1854 GMT (1:54 p.m. EST)

DROP. Pegasus is away. Standing by for ignition.

1853 GMT (1:53 p.m. EST)

T-minus 30 seconds. The first stage flight control fins have now transferred to battery power. This will allow the fins to undergo a steering test in the next few moments. Also, the L-1011 aircraft is on the proper heading to release Pegasus.

1853 GMT (1:53 p.m. EST)

T-minus 1 minute and counting. Range Safety will soon give a go for launch.

1852 GMT (1:52 p.m. EST)

T-minus 2 minutes and counting.

1850 GMT (1:50 p.m. EST)

T-minus 4 minutes and counting. The countdown clocks have resumed and all systems are go. The L-1011 is flying at an altitude of 40,000 feet.

1849 GMT (1:49 p.m. EST)

The countdown has been stopped at T-minus 4 minutes to await proper positioning of the L-1011 aircraft.

1846 GMT (1:46 p.m. EST)

After being released from the L-1011, the Pegasus rocket will free fall for five seconds before the first stage is ignited. The solid-fuel stage will continue to fire for about 69 seconds. Separation of the first stage will occur at T+plus 90 seconds, and the solid-fuel second stage will ignite less than a second later.

The protective nose fairing enclosing the ORBCOMM satellites will be jettisoned at T+plus 2 minutes. Burnout of the second stage is expected T+plus 2 minutes, 44 seconds. The spent stage will then be jettisoned at T+plus 7 minutes, 27 seconds, and third stage ignition will follow 11 seconds later. Third stage, a sold-fuel booster, will burn out at T+plus 8 minutes, 46 seconds and separate from the HAPS upper stage about 59 seconds later.

The HAPS liquid-fuel stage will ignite for the first time at T+plus 9 minutes, 46 seconds and burn until +Tplus 10 minutes, 24 seconds. At that point, the HAPS and attached ORBCOMM satellites will coast for about 40 minutes before the stage is reignited. Deployment of the seven ORBCOMM satellites will occur one at a time over an hour into flight.

1841 GMT (1:41 p.m. EST)

Weather conditions in the launch box over the Atlantic Ocean have been determined to be acceptable for flight today. All systems remain ready for launch.

1838 GMT (1:38 p.m. EST)

The Pegasus rocket's flight termination system is on internal power.

1837 GMT (1:37 p.m. EST)

Orbital launch conductor has complete a readiness poll and the go was given to transfer the rocket's flight termination system to internal power. The FTS would be used to destroy the rocket in the event of a problem during launch.

1832 GMT (1:32 p.m. EST)

Now about 20 minutes away from today's scheduled launch of the Pegasus rocket and seven ORBCOMM satellites. Officials are not working any problems.

1826 GMT (1:26 p.m. EST)

Orbital Sciences' air-launched Pegasus rocket will be making its 28th flight today. The vehicle is currently ride a three-year stretch of consecutive successful launches, placing 35 satellites into space. If today's mission goes as expected, it would make the 14th straight success.

1820 GMT (1:20 p.m. EST)

There are no problems to speak of today. The countdown timeline is proceeding smoothly toward launch at 1:51 p.m. EST.

1811 GMT (1:11 p.m. EST)

Officials continue to target 1:51 p.m. EST for the drop of Pegasus. Today's available launch window extends from 1:46 to 2:01 p.m. EST.

1809 GMT (1:09 p.m. EST)

The Range has reported it is not working any problems. L-1011 is currently at an altitude of 29,700 feet.

1805 GMT (1:05 p.m. EST)

The L-1011 has completed a turn toward the east. The aircraft took a southerly trek away from Wallops. Altitude is currently 23,000 and velocity is about 678 feet per second.

1759 GMT (12:59 p.m. EST)

Launch managers are watching video of the Pegasus rocket from the T-38 chase plane. The video is used to ensure the rocket is in good shape for the launch. Current altitude of the L-1011 aircraft is 17,000 feet.

1756 GMT (12:56 p.m. EST)

Wheels up for the L-1011 carrier aircraft. "Stargazer" has taken off from Wallops headed for the launch point about 50 miles off the Virginia coastline over the Atlantic Ocean.

1754 GMT (12:54 p.m. EST)

The T-38 chase plane stationed at Langley has been given a go to depart Wallops. The aircraft will fly along side the L-1011 during today's launch and provide video of the Pegasus launching.

1751 GMT (12:51 p.m. EST)

The ground launch team has just reported they are go for departure of the L-1011 aircraft.

1740 GMT (12:40 p.m. EST)

All systems are reported go for launch at this time.

Today's mission is being managed from the Wallops Flight Facility in Virginia. This will be the eighth Pegasus mission in which Wallops has served as the control site.

1730 GMT (12:30 p.m. EST)

The "Stargazer" L-1011 carrier aircraft has rolled to the end of Runway 22 at Wallops Flight Facility. Departure of the plane with the Pegasus rocket aboard is scheduled for about 20 minutes from now.

1500 GMT (10:00 a.m. EST)

Orbital Sciences is scheduled to launch a Pegasus rocket today to place seven new satellites into space for the ORBCOMM data relay network. The air-launched Pegasus will be dropped from the belly of an L-1011 carrier jet about 50 miles off the Virginia coastline of the U.S. An available launch window will extend from 1:46 to 2:01 p.m. EST (1846-1901 GMT), with Pegasus release targeted for 1:51 p.m. EST.

The mission will be staged from NASA's Wallops Flight Facility in Southeastern Virgina. Orbital ferried the L-1011 and rocket to the launch site from the Pegasus home base at Vandenberg Air Force Base, California, on Tuesday. Departure of the aircraft from Wallops is expected at about 12:50 p.m. EST (1750 GMT) today, at which time the L-1011 will fly toward the intended "drop box" for launch.

Read our preview story for a full description of today's mission.

Flight data file
Vehicle: Pegasus XL
Payload: 7 ORBCOMMs
Launch date: Dec. 4, 1999
Launch window: 1846-1901 GMT (1346-1401 EST)
Staging site: Wallops Flight Facility, Virginia

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