GPS III SV-04 Launch

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jimh
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GPS III SV-04 Launch

Postby jimh » Sun Sep 20, 2020 9:06 am

According to NEXTSPACEFLIGHT.COM, the launch of GPS III SV-04 is now scheduled for October 1, 2020 at midnight UTC, or about 7 p.m. September 30, 2020.

The fourth GPS III satellite will be carried into orbit by a SpaceX Falcon 9 rocket.

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Re: GPS III SV-04 Launch

Postby jimh » Wed Sep 30, 2020 6:00 pm

The GPS III SV-04 launch is now scheduled for October 02, 2020 at 9:43 PM ET.

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Re: GPS III SV-04 Launch

Postby jimh » Fri Oct 09, 2020 12:26 am

The launch of GPS III SV-04 was attempted about 9:45 p.m. on Friday, October 2, 2020, but at T-minus-2-seconds there was an abort due to an overpressure condition in a rocket engine pumping system.

The FALCON9 launch vehicle has been laid over to horizontal. The recovery ships have returned to port. There is presently no launch attempt scheduled or announced. It appears that SpaceX will be investigating the problem with the FALCON9.

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Re: GPS III SV-04 Launch

Postby jimh » Mon Nov 02, 2020 5:32 pm

GPS III SV-04 launch is now scheduled to occur on November 5, 2020 at 6:24 p.m. EST.

UPDATE:
SpaceX is targeting Thursday, November 5 for a Falcon 9 launch of the United States Space Force’s GPS III Space Vehicle 04 from Space Launch Complex 40 (SLC-40) at Cape Canaveral Air Force Station in Florida. The 15-minute launch window opens at 6:24 p.m. EST, 23:24 UTC, and a backup opportunity is available on Friday, November 6 with a 15-minute backup window opening at 6:20 p.m. EST, 23:20 UTC.

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Re: GPS III SV-04 Launch

Postby jimh » Fri Nov 06, 2020 3:00 am

The GPS III SV-04 satellite was launched successfully on November 5, 2020 at the scheduled 6:24 p.m. launch window. The satellite is now in a transfer orbit to its final position in a circular orbit at an altitude of 12,500-miles above Earth.

SpaceX was able to recover the first stage rocket by an autonomous landing on their drone ship at sea.

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Re: GPS III SV-04 Launch

Postby jimh » Sun Nov 08, 2020 10:35 am

The GPS III SV-04 space vehicle is also known by the nickname Sacagawea, and as SVN-77. It is intended to rise into final orbit in GPS Plane B and Slot 03, where it will replace SVN-44, which is broadcasting with PRN-28. The new satellite SVN-77 will broadcast with PRN-14 when it comes on line in several months.

The SVN-44 space vehicle (to be replaced) was launched July 16, 2000 and is a GPS IIR type. The "R" is for replenishment or replacement. There were twelve satellites in this series successfully launched. The design life of the GPS IIR satellites was ten years. SVN-44 has been in service for 20-years, about double its design life.

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Re: GPS III SV-04 Launch

Postby jimh » Tue Dec 08, 2020 5:27 pm

Shortly after separation of the GPS III SV-04 space vehicle from its Space-X FALCON 9 Merlin vacuum engine second stage, the GPS space vehicle was in communication with ground control. The vehicle is now in the process of raising its orbit to its final circular medium-earth-orbit trajectory of 12,500-km using its on-board liquid propulsion engine. This process will take several weeks. More at

https://news.lockheedmartin.com/2020-11-05-Fourth-Lockheed-Martin-Built-GPS-III-Satellites-On-Board-Engine-Now-Propelling-It-To-Orbit

Establishing ground control after launch is an extraordinarily important step in the successful deployment of the satellite. During the orbit raising the photo-voltaic panels that produce electrical energy from sunlight are not deployed, and the satellite electrical power is obtained from batteries aboard the spacecraft. Once at final orbit height, the solar panels will be deployed. These panel then generate electrical power for on-going operation of the spacecraft during its service life, which could be 20-years or more.