Wednesday, August 4, 2010

S. Korea Begins Anti-Sub Exercises Near Border


SEOUL - South Korea on Aug. 5 launched its largest-ever anti-submarine exercise near the disputed sea border with North Korea, the defense ministry said, despite the North's threats of retaliation.

The South has warned the North it will not tolerate provocations during the five-day naval drill in the Yellow Sea.

The exercise is designed as a warning to the North following accusations it used a torpedo in March to stink a South Korean warship. Forty-six sailors died in the Cheonan tragedy.

Military officials say 29 ships, including a submarine and destroyer, 50 fixed-wing aircraft and 4,500 army, navy, air force, marine and coast guard personnel are taking part.

A ministry spokesman told AFP that underwater firing drills would take place close to Baengnyeong, the nearest island to the disputed maritime border with the North. Cheonan went down just to the southwest of the island.

AEHF satellite is slated for launch Aug. 12.

The U.S. Air Force says the first Lockheed Martin Advanced Extremely High Frequency (AEHF) satellite is slated for launch Aug. 12.

Once in operation after months of testing, AEHF will begin ushering in a new era for protected, jam-proof communications. This mission is now handled by the Milstar constellation.

AEHF will be able to send high-data-rate communications to users around the globe (except for the extreme polar regions).

The first AEHF will provide more capacity than the entire Milstar constellation and it will provide a five-fold increase in the number of terminals services, says Col. William Harding, vice commander for the wing that oversees Milsatcom procurement at the Air Force Space and Missile Systems Center.

He declined to provide the final orbital location for AEHF-1. After about three months of orbit raising, however, it will be placed at a 90-deg. West location to allow for in-orbit checkout. This testing will take about 3-4 months, Harding says.

The extended data-rate (XDR) services, a unique high-data-rate protected communications capability offered by AEHF, could come online about one year after launch.

AEHF will have crosslinks capable of working with the Milstar satellites in orbit today and it also will operate with terminals already in the field.

The launch will require the United Launch Alliance Atlas V 531 configuration with three solid-rocket motors. The launch window at Cape Canaveral, Fla., opens up just after 7 a.m. on Aug. 12.

Canada, the Netherlands and the U.K. all participated in AEHF development, though Harding declined to say how much money each partner provided for the work and when capability will be delivered to them.

AEHF has been through its share of turbulence. The program grew out of the loss of a Milstar satellite in 1999. It was originally thought a national team would develop the system, but that was later amended; Lockheed Martin is the lead with Northrop Grumman providing the payload. The program’s projected constellation size also has ebbed and flowed. Now officials say they are planning for long-lead items for satellite 4, with a production contract not yet negotiated.

The Pentagon’s Selected Acquisition Reports, however, outline six satellites, a signal that the constellation could grow.

In the December 2009 SAR, the Pentagon estimates AEHF cost at $12.449 billion for six satellites. In 2002, the program was estimated to cost about $6.086 billion for three satellites.

AEHF-2 is slated for launch next spring with the third satellite to follow in early 2012. Transition to global XDR communications will not occur until later in the decade when four satellites are in orbit.

The design life for AEHF satellites is 14 years. Milstars were expected to last 10 years; all Milstar spacecraft have exceeded their seven-year mission duration expectation.

Concept: Lockheed Martin


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