Airline industry representatives and a US transportation official told members of Congress yesterday that LightSquared's planned 4G LTE network would interfere with a GPS-based navigation system that government and industry has invested $8 billion in.

The Federal Aviation Administration and industry "have invested as much as $8 billion into NextGen," which is designed to "transform America’s air traffic control system from the aging groundbased system of today to a satellite-based system of the future," US Department of Transportation Deputy Secretary John Porcari said in testimony given at a Transportation and Infrastructure subcommittee hearing.

LightSquared is battling for approval of its proposed network, but government testing has indicated the network would interfere with 75 percent of GPS devices. LightSquared has called the test results a "distortion of truth" and said that it's the responsibility of GPS device sellers to redesign their products so as not to be interfered upon by spectrum licensed to LightSquared. The Federal Communications Commission's preliminary approval of the LightSquared network is being examined by members of Congress, with US Rep. Greg Walden (R-OR) asking "how did that process fail?"

Porcari argued yesterday that "LightSquared’s proposal would require constant, individual monitoring and adjustments to over 40,000 broadcasting sites nationwide, to ensure that they could be, and would remain, consistent with air safety requirements. This is simply not practical. Therefore, based upon all of the testing and analysis that has been performed, there appears to be no practical solutions or mitigations that would permit the LightSquared broadband service, as proposed, to operate in the next few months or years without significantly interfering with GPS."

The NextGen system relies upon GPS technology "to shorten routes, save time and fuel, reduce traffic delays, increase capacity, and permit controllers to monitor and manage aircraft with greater safety margins," Porcari said. The Federal Aviation Administration estimates that by 2013, 60,000 aircraft in the US will be equipped with GPS.

Members of Congress also heard from Airlines for America, a trade group representing most of the country's major airlines. Tom Hendricks, senior VP for safety, security, and operations predicted "ruinous effects on aviation" from GPS interference caused by the LightSquared proposal. "GPS will be the backbone of air navigation both domestically and internationally in the coming years," Hendricks said. "Interference with its accessibility or reliability would be catastrophic for civil aviation and the communities that depend on air transportation."

The ground-based air navigation system "has become increasingly defined by its limitations," he said. "Users of the system have, for the most part, had to fly from one ground navigation aid to the next, often resulting in circuitous routings. This inefficiency wastes time and fuel. It also restricts the number of routings that aircraft can use, which in turn constricts capacity growth."

The FAA went so far as to claim in July that the time wasted retrofitting aircraft to accommodate LightSquared signals would lead to 794 deaths over a ten-year period. LightSquared dismissed the report as being based upon older versions of its network proposal, but battles around the proposal continue on. On Tuesday this week, LightSquared called on the FCC to develop new standards requiring GPS devices to avoid using spectrum licensed to LightSquared.

"Two rounds of testing by independent and government entities have confirmed that the interference experienced by the commercial GPS receivers is the result of an industry decision to design and sell poorly filtered devices that purposefully depend on spectrum licensed to LightSquared for accuracy." LightSquared said in a statement on its website. "If sensible standards were in place, the GPS industry would not be facing the current interference problems and consumers would benefit from a more efficient use of spectrum. Furthermore, the way would be clear for LightSquared to launch its new nationwide wireless broadband network funded by a $14 billion private investment in the nation’s broadband infrastructure."