June 28, 2011 - In a letter sent to the U.S. House Aviation Subcommittee, the world’s largest pilot union declared adamant opposition to a private company’s bid to expand its broadband communications services.

This expansion would jeopardize the global positioning system (GPS) and threaten the tremendous contribution that the satellite-based navigation system makes to ensuring efficient and safe airline operations. 

“Over more than two decades, the invaluable navigation information available through GPS has enabled air transportation to take an enormous leap forward in safety and efficiency,” said Capt. Lee Moak, ALPA’s president.

Capt. Moak sent the letter to House Aviation Subcommittee Chairman Tom Petri (R-WI) in preparation for the subcommittee’s hearing titled “GPS Reliability: A Review of Aviation Industry Performance, Safety Issues, and Avoiding Potential New and Costly Government Burdens.”

Since 1983, when GPS became available for civilian use, the system has evolved to become an indispensible tool for aircraft navigation, all-weather approaches and landings, surveillance, maintaining separation between aircraft, and pilot situational awareness.  

GPS signals are low-power by design to allow them to be based on satellites, but this low-energy environment also makes them susceptible to interference from other radio transmissions. For this reason, only low-powered, satellite-based signals have historically been permitted in the radio frequencies that are closest to GPS bandwidth. In dramatic contrast to this safety-based approach, LightSquared, a privately held broadband provider, proposes to deploy 40,000 high-powered, ground-based transmitters in the radio frequency spectrum that is directly adjacent to GPS bandwidth.  

Rigorous industry and government testing demonstrates that, if the proposal were to go forward, GPS would be inaccessible over large regions of the United States at normal operational altitudes for airliners. As a result, airline pilots would lose a fundamental navigation tool that is particularly beneficial in mountainous terrain, remote areas, and bad weather. 

“In addition to safety and efficiency concerns, any proposal that compromises GPS as a crucial tool airline pilots use to provide safe and efficient air transportation in the United States also jeopardizes the enormous contribution that the airline industry makes to the U.S. economy and the tens of thousands of jobs it supports,” continued Capt. Moak.

Along with immediate operational issues, jeopardizing GPS would also seriously affect existing efforts to modernize the U.S. air traffic control system. ALPA strongly supports airspace modernization through NextGen and its potential to enhance safety, increase capacity and efficiency, and protect the environment. The FAA has already invested more than a billion dollars in GPS-based technology that is designed to replace radar-based surveillance of aircraft, and as NextGen continues to mature, GPS will become increasingly important. 

“The safety and efficiency of aviation operations today already depend on the extremely accurate navigation information provided by GPS,” concluded Capt. Moak. “ALPA applauds the U.S. House Aviation Subcommittee for holding a hearing on this issue and underscoring the unmatched benefit that GPS provides to air transportation. The LightSquared proposal must not be approved or deployed unless we have clear evidence that the GPS system relied on by millions for safe and efficient air travel is fully protected.”