Airlines have been split on whether to go with a ground-based system or with satellite-based systems.
The re-instituted missile ground-based system plan will put 14 more long-range interceptors in Fort Greely, Alaska by 2017 to supplement the 30 already existing on the West Coast.
The ground-based system offered by Gogo, which connects a Wi-Fi hot spot installed in a jet to one of 135 antennas Gogo has on the ground in North America, has been running on commercial aircraft since 2008.
There are, moreover, other ways to provide such a defense -- notably, from the sea using modified AEGIS fleet air defense ships -- that could enable a national missile defense to be fielded for a fraction of the cost of the ground-based system.
CENTERFORSECURITYPOLICY: Sea-Based Missile Defenses -- for the Allies, for the U.S.
The Bush Administration has a sluggish, low-key missile defense effort under way: a limited ground-based system deployed in Alaska and California, which won't be much of a deterrent in today's world, and a still underdeveloped sea-based system modeled on the U.S. Navy's Aegis vertical launch system.
Such systems include all phases of the Phased Adaptive Approach to missile defenses in Europe, the modernization of the Ground-based Midcourse Defense system, and the continued development of the two-stage Ground-Based Interceptor as a technological and strategic hedge.
Cost and Capability: Cost concerns alone should dictate rejection of a completely ground-based defensive system in favor of one that uses both ground and space elements.
Just one year ago, the Bush administration announced it would keep the ground-based LORAN system operational to serve as a backup for the satellite-based global positioning systems, which are becoming ubiquitous in cars, planes and ships.
While this is a significant sum, to be sure, if an apples- to-apples comparison were made, the price of purchasing and operating modern fighter aircraft wings or a class of surface ships or submarines would significantly exceed that associated with a ground-based NMD system.
CENTERFORSECURITYPOLICY: Sea-Based Missile Defenses -- for the Allies, for the U.S.
The FAA says funding for the new fee system, combined with federal money, would shift the 40-year-old ground-based air traffic control system to a satellite-based, cockpit-to-cockpit system that is safer and more efficient.
Every commercial flight that takes off from the United States is currently monitored by a radar-based ground system that has been in place since WWII.
Each probe can pick up GPS signals and signals from eLoran, an enhanced version of Loran, the ground-based terrestrial radio-navigation system first used by the American and British navies during the second world war.
Whether the U.S. system of ground-based interceptors are the right response quickly became a matter of debate Friday.
WSJ: U.S. to Boost Missile Defenses in Response to North Korea
Ideally, an underlay of ground-based interceptors would also be deployed in a layered SDI system.
Deterrence: The first phase system should be comprised of ground and space-based sensors and interceptor systems.
Their antenna system is also closely related to a ground-based wireless technology called local multipoint distribution service (LMDS).
The Center believes that the necessary degree of protection can only be acquired by deploying an orbiting defense system, perhaps with a modest underlay of ground-based interceptors.
Interestingly, Mr. Davis has cited the importance of layered or "tiered" defense among his rationales for restarting the canceled E2I secondary interceptor for the single ground-based defense site he advocates -- despite the fact that the E2I system does not represent an independent layer.
The system the Administration is looking at would link a network of ground-based radars and space-based sensors with 100 missile interceptors located at a single site.
Its Iridium satellite-based global phone system switches all calls in the sky without using any ground stations, an impossibly difficult task.
He and his colleagues have made a start on this at Army City, where they are creating a system that will swallow, digest and combine data from satellites, aircraft and ground-based sensors, aligning them in a single, computer-based model of the site.
Both cars can be equipped with optional torque vectoring, a brake-based system built to augment the mechanically locking rear differential and help put power to the ground.
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