Mittwoch, 15. Juli 2015 - 18:25

Raumfahrt - Erfolgreicher Start von Atlas V mit GPS IIF-10 USAF Satelliten

7.06.2015

Rocket/Payload: An Atlas V 401 will launch the GPS IIF-10 mission for the U.S. Air Force.
Date/Site/Launch Time: Wednesday, July 15, from Space Launch Complex (SLC)-41 at Cape Canaveral Air Force Station, Florida.
Mission Description: GPS satellites serve and protect our warfighters by providing navigational assistance for U.S. military operations on land, at sea, and in the air. Civilian users around the world also use and depend on GPS for highly accurate time, location, and velocity information.GPS IIF-10 is one of the next-generation GPS satellites, incorporating various improvements to provide greater accuracy, increased signals, and enhanced performance for users.
Launch Notes: GPS IIF-10 marks the 55th Atlas V launch since the vehicle’s inaugural launch in 2002 and the 27th flight of the 401 configuration. Every operational GPS mission has launched on a ULA or heritage rocket.

Quelle: ULA

Update: 24.06.2015

Stacking of 55th Atlas 5 rocket starts

File image of Atlas first stage stacking. Credit: NASA-KSC

CAPE CANAVERAL — Beginning its fourth launch campaign of the year, the Atlas 5 rocket program has started stacking the vehicle that will boost a satellite 11,000 miles high for the Global Positioning System.

United Launch Alliance crews commenced the assembly work today at Cape Canaveral’s Vertical Integration Facility for the upcoming mission carrying the Air Force’s GPS 2F-10 navigation spacecraft.

Liftoff is targeted for July 15 during a morning window of 11:36 to 11:55 a.m. EDT (1536-1555 GMT).

The 189-foot-tall rocket will be flying in the basic, 401-variant that features an RD-180 main engine powering the first stage and an RL10 on the Centaur upper stage. The satellite will be enclosed in a 39-foot-long, 14-foot-diameter aluminum nose cone for atmospheric ascent.

The GPS 2F-10 is destined for the constellation 11,000 nautical miles high, inclined 55 degrees to either side of the equator. The network serves the U.S. military and civilian users around the globe for precision navigation and timing services.

This new satellite will take the place of the 11-year-old GPS 2R-11 craft launched aboard Delta 303 in March 2004 into Plane C, Slot 3 of the constellation. It moves to a backup role in the network once GPS 2F-10 enters service about a month after launch.

To make numerical room for the new addition to the constellation, the GPS 2A-26 launched aboard Delta 237 in July 1996 will be decommissioned following the GPS 2F-10 launch.

It will be the second GPS launch this year, following a Delta 4 deployment flight successfully carried out March 25. One more in 2015 is planned by Atlas in October.

This year has seen three Atlas 5 rockets fly so far, launching its heaviest payload ever — the Navy’s MUOS 3 communications satellite — in January, NASA’s MMS magnetospheric science experiment in March, valued at $1.1 billion, and the Air Force’s X-37B spaceplane in May on another secretive voyage.

The rocket has six more missions on the manifest for 2015, including launches of the GPS 2F-10 satellite, the MUOS 4 spacecraft, a classified NRO payload from Vandenberg, Mexico’s Morelos 3 communications satellite, GPS 2F-11 and Orbital ATK’s Cygnus cargo-delivery craft for the International Space Station.

The stacking work for AV-055 began this morning as the bronze-colored, 106.6-foot-long, 12.5-foot-diameter first stage was pulled to the VIF doorway, erected upright and hoisted inside the building to be put aboard the mobile launcher platform.

Known as the Common Core Booster, the stage produces 860,000 pounds of thrust to lift the rocket off the ground. It burns kerosene fuel and supercold liquid oxygen during the initial minutes of flight.

In the coming days, the barrel-like interstage adapter will be added and then the Centaur upper stage will be lifted in place. Centaur is 41.5 feet in length, 10 feet in diameter and is fueled by liquid hydrogen and liquid oxygen.

The payload is undergoing its own processing at a nearby Air Force facility. It will be delivered to the VIF and mated to the Atlas-Centaur in early July.

GPS 2F-10, a 3,400-pound, modernized navigation satellite made by Boeing, features improved accuracy, enhanced internal atomic clocks, better anti-jam resistance and a civil signal for commercial aviation. It is the 10th of 12 Block 2F satellites to launch.

The launch will be the 55th Atlas 5 rocket since 2002 and the 21st for the Air Force since 2007. It also marks the 70th GPS satellite launch since 1978, the 15th to use an Atlas rocket and the fourth Block 2F on Atlas. For United Launch Alliance, it is the company’s 97th launch overall since 2006 and the sixth this year.

Quelle: SN

Update: 14.07.2015

ULA Atlas-V and Delta-IV Poised to Launch Air Force GPS and WGS Satellites July 15 and 22

Two U.S. military space missions, one launched by an Atlas V and the other by a Delta IV, are set to roar off Cape Canaveral’s launch pads within seven days of each other, initiating six months of intense and diverse military space launch activity.

The planned July 15 launch from Cape Canaveral of a United Launch Alliance (ULA) Atlas V 401 rocket carrying the U.S. Air Force GPS 2F-10 navigation satellite will kick off the busy pace. It will also hasten the phaseout of the Boeing 2F line toward Lockheed Martin’s GPS III operations in 2017.

The liftoff of GPS 2F-10 on its Atlas V 401, with a four-meter faring and no solid rocket boosters, is scheduled to fly within a 19-minute launch window that opens at 11:36 a.m. EDT and closes at 11:55 a.m. EDT. The mission will mark the fourth Atlas V launched from the Cape in 2015.

The second military mission also planned for launch from Cape Canaveral this month is the seventh USAF Wideband Global SATCOM (WGS) satellite, planned for liftoff from Complex 37B July 22 on a ULA Delta IV Medium Plus with four solid rocket boosters.

The July 22 Delta IV liftoff is scheduled within a 45-minute launch window that opens at 8:07 p.m. EDT and closes at 8:52 p.m. EDT.

The GPS and WGS launches make for a challenging operations tempo at the USAF’s 45th Space Wing that manages Cape Canaveral. Additional launches in this military space launch surge will also make for a busy pace at the 30th Space Wing at Vandenberg AFB, Calif., later this year and early next year with top secret reconnaissance flights of Intruder ocean surveillance and Topaz radar imaging spacecraft.

Both the GPS and WGS military space assets are especially important to USAF drone bandwidth and navigation during intelligence and strike operations over Iraq and Syria. And the WGS Ka-band system specifically is used to route key drone-gathered intelligence imagery to hundreds of 18-inch diameter antennas that can be carried in the rucksack of any soldier or Marine.

Also, GPS spacecraft are increasingly capable of detecting underground nuclear testing as North Korea has done and Iran could potentially do in the future.

This underground nuclear test detection capability is very important locally to the highly secret Air Force Technical Applications Center (AFTAC)—charged with nuclear treaty related reconnaissance, detection, and enforcement. AFTAC is co-located with the 45th Space Wing at Patrick AFB about 15 miles south of the Cape’s pads.

GPS satellites can do this nuclear monitoring by detecting the “traveling ionospheric disturbance” that accompanies each underground explosion, said geo engineer Dorota Grejner-Brzezinska at Ohio State University.

For example, moments after the July 25, 2009, North Korean underground nuclear weapon detonation 11 GPS receivers picked up GPS satellite data showing a sudden spike in atmospheric electron density, according to the Bulletin of Atomic Scientists.

Two more Boeing GPS 2F spacecraft will remain to be launched after 2F-10 to complete the 12 satellite line that began operation with the first 2F launched in May 2010 on a Delta IV. Each 2F has a 12-year service life.

There are eight new GPS III spacecraft planned. They are to have a 15-year design life, three times the accuracy, eight times the anti-jam capability, and much stronger signal power than the previous Boeing GPS spacecraft.

The 45th Weather Squadron forecasts that the GPS Atlas V mission should have a 70 percent chance of acceptable weather for both its July 14 Mobile Launcher rollout to Complex 41 and the launch itself on the 15th. The 30 perfect unfavorable odds come with the potential presence of excessive cumulus clouds. Given mid summer in central Florida, the weather for the WGS-7 launch July 22 will likely be similar.

Powered by 860,000 lbs (390,089 kg) of thrust from its Energomash RD-180 engine, the Atlas will fly northeast before ignition if its 24,750-lb (11,226-kg) thrust second stage Centaur Aerojet Rocketdyne RL10B-2 engine. The Atlas will place the 3,400-lb (1,542-kg) satellite into a 12,541 mi. (20,182 km.) orbit inclined 55 deg.

The new GPS will replace the 11-year-old GPS 2R-11 launched in 2004. That satellite will take on a backup role in the expanded 31 satellite GPS constellation that ensures at least 24 satellites are operational at any given time, with mostly four spacecraft in view of any given spot on Earth. As part of this change, the 19-year-old GPS 2A-26, launched in 1996, will be decommissioned.

There are about $4 billion in Air Force, Navy and National Reconnaissance Office space assets involved in the military space surge over the next six months. Atlas V launches cost about $100 million, while Delta IV Medium flights cost about $164 million. Costs involved with the sveven U. S. spacecraft involved in the surge are:

—July 15, the $245 million USAF GPS 2F-10 on an Atlas V from the Cape.

—July 22, the $566 million USAF WGS-7 on a Delta IV Medium from the Cape.

—Aug. 27, the $611 million Navy MUOS Mobile User Objective System on a Cape Atlas V.

—Sept. 25, the approximately $300-500 million class National Reconnaissance Office (NRO-55) twin Intruder secret ocean surveillance spacecraft planned for launch from Vandenberg on an Atlas V.

—Oct. 30, the $245 million GPS 2F-11 on a Cape Atlas V.

—Jan. 26, the $245 million GPS 2F-12, the final 2F mission, on a Cape Atlas V.

—Feb. 10, the approximately $1 billion NRO-45 National Reconnaissance Office Topaz 4 high resolution imaging radar that has replaced the 30-year-old Lacrosse imaging radar design.

The planned July 22 launch of WGS-7 will mark the second Delta IV launch from Cape Canaveral in 2015. Each Boeing WGS is a large, powerful satellite weighing 13,000 lbs (5,897 kg), with solar arrays spanning 157 ft (48 meters).

The Delta IV will liftoff on 1.82 million lbs (825,538 kg) of thrust from its Aerojet Rocketdyne RS-68 oxygen/hydrogen engine and four solid rocket boosters. Its RL10B-2 upper stage engine will propel WGS-7 into a super synchronous orbit, then the satellite will descend to its desired secret geosynchronous orbit parking spot. It will undergo several weeks of operational testing.

The WGS system provides worldwide, flexible, high-data rate and long-haul communications for marines, soldiers, sailors, airmen, the White House Communication Agency, the U.S. State Department, international partners, and other special users. The Air Force says the WGS system forms the backbone of the U.S. military’s global satellite communications capability.

Each WGS satellite provides service in both the X- and Ka-frequency bands, with the unprecedented ability to cross-band between the two frequencies onboard the satellite. WGS augments the one-way Global Broadcast Service (GBS) service through new two-way Ka-band service.

Each WGS satellite is digitally channelized. These characteristics provide a quantum leap in communications capacity, connectivity, and flexibility for U.S. military forces and international partners, while seamlessly integrating with current and future X- and Ka-band terminals.

The Air Force says: “WGS provides essential communications services, allowing Combatant Commanders to exert command and control of their tactical forces, from peace time to military operations. Tactical forces will rely on WGS to provide high-capacity connectivity to the Defense Information Systems Network (DISN).”

International partners participating on the WGS program are Australia, Canada, Denmark, Luxembourg, The Netherlands, and New Zealand. Australia procured WGS-6 as its own dedicated wideband asset.

A WGS satellite can provide up to eight steerable and shaped X-band spot beams formed by separate transmit/receive phased array antennas. Also, it can project 10 Ka-band beams by independently steered and diplexed antennas, including three with selectable RF polarization.

The Air Force’s GPS IIF-10 satellite, encapsulated inside a 4-meter payload fairing, is mated to an Atlas V rocket at the Vertical Integration Facility or VIF. Photo: ULA

Quelle: AS

Update: 15.07-2015 / 13.25 MESZ