Rise and shine: Atlas 5 rocket successfully soars at dawn
BY JUSTIN RAY
Posted: August 14, 2010
A sophisticated satellite was launched into space today to improve the preeminent path of communications between the president, military commanders and troops on the battlefield, ensuring a survivable line of contact even in hellish scenarios of nuclear warfare.
Three solid-fueled boosters mounted to the launcher's kerosene-fed first stage provided a substantial kick in speed and power coming off the pad, sending the 197-foot-tall, million-pound Atlas blazing a trail toward the east.
A scant five minutes later, the rocket had ascended out of the atmosphere and the cryogenic Centaur upper stage lit its liquid hydrogen and liquid oxygen engine for the first of two burns. The second firing delivered the necessary push to deploy the AEHF 1 satellite into a geosynchronous transfer orbit.
The 13,420-pound payload separated from the rocket 51 minutes after liftoff while cruising high above the Indian Ocean.
"The team of folks behind the first AEHF mission is a great set of Americans who have dedicated many years of their life to put this satellite into orbit," said Col. Michael Sarchet, commander of the Protected Satellite Communications Group at the Space and Missile Systems Center.
"AEHF is a very sophisticated satellite because it is built to provide the highest levels of protection for our nation's most critical users. Encryption, low probability of intercept and detection, jammer resistance and the ability to penetrate the electro-magnetic interference caused by nuclear weapons are essential features when communication can be of the highest priority," said Sarchet.
This maiden AEHF bird should be ready, if all goes well, to enter service early next year from an orbital location dictated by the needs at that time.
Controllers plan to spend the next 100 days or so using the craft's conventional and exotic ion propulsion systems to circularize the orbit 22,300 miles over the equator at 90 degrees West longitude for months-long testing.
"It really does mark a new era for us. Milstar was the first protected (communications satellite) system that we ever put up and it's done a great job for us. We launched the first one back in February 1994. If you add up all the on-orbit life of the five vehicles up there operating, we've got over 56 years experience with Milstar," said Col. William Harding, the Military Satellite Communications Systems Wing vice commander at Los Angeles Air Force Base.
"But it is getting older. All five of the spacecraft are past their 7-year mean mission duration and two of them are past their 10-year design life. So it's time to move on to the next version -- AEHF."
Designers say one AEHF spacecraft has more capacity than Milstar's five-satellite constellation combined and its faster data rates will benefit tactical military communications, enabling higher quality maps, targeting data and live video to be transmitted without being detected by the enemy.
"AEHF also will provide a five-fold increase in the numbers of communication coverage opportunities so that more terminals spread over more of the globe will be able to access more communications resources," Harding said.
The new satellites will be crosslinked with the existing Milstars, and the AEHF are compatible with existing user equipment.
"The benefits also include use of small terminals that can provide high data rate channels, resilience against electronic warfare and cyber attack, and survivable, high availability communications connections across the full spectrum of military operations from peacetime training to nuclear warfare," Sarchet said.
Communications relayed through AEHF can include critical support to Special Operations, situational awareness for Army troops, giving last-minute targeting information to en-route Air Force fighters and transmitting Tomahawk missile updates to the Navy.
For the nation's nuclear forces, these hardened satellites would be the communications lifeline for crisis response and war planning in the most dire circumstances imaginable.
"Communications links for control of the U.S. nuclear force, force direction from the president of the United States, missile attack early warning, missile defense, communications support to Special Operations and high-speed anti-jam protected communications for tactical forces," said Sarchet.
Milstar and its AEHF successor are far different from the other types of communications satellites operated by the military. The Navy-led UHF system provides mobile communications to a large number of user terminals but at low data rates. The Defense Department's backbone network using DSCS and the newer Wideband Global SATCOM craft offers very high data rates but lower mobility.
Harding says when a critical piece of information needs sent and it must get there, you call upon "the FedEx" of military communications with Milstar and AEHF.
But developing state-of-the-art satellites hasn't been cheap. The Air Force says the current scope of the AEHF contract totals $6.462 billion.
Constructed around Lockheed Martin's A2100 satellite model with a 14-year design life, the AEHF satellites feature power-generating solar panels stretching 89 feet tip-to-tip and two antenna-laden deployable wings.
"The satellite uses a mix of phased array and dish antennas to create over 194 coverage areas on the ground," said Sarchet.
The improved data rates on AEHF vary from 75 bits per second to 8.2 million.
"Speaking for Lockheed Martin Space Systems, we have great confidence based on our proven Milstar experience, our flight-proven A2100 spacecraft bus and our successful Advanced EHF integration and test program that we have built a satellite that will meet our customer's expectations and set a new standard of excellence for the U.S. military," said Mike Davis, the company's vice president for AEHF.
"The collective team has worked extremely hard to prepare this important spacecraft for flight. We all look forward to achieving mission success."
Two more AEHF satellites are progressing through factory testing. AEHF 2 should be ready for shipment to the launch site by the end of this year for liftoff aboard another Atlas 5 rocket in early 2011, and AEHF 3 could fly in early 2012, Davis said.
Long-lead items for AEHF 4 have been ordered. However, the full satellite hasn't been placed under contract yet, Harding said. At least four spacecraft are needed to cover the globe.
The United Kingdom, Canada and the Netherlands are partners in the AEHF program, providing some funding in exchange for a corresponding amount of resources from the satellites.
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