Because the low-power, high-frequency characteristics of GPS make it vulnerable to jamming, eLoran, with its high power, low frequency, enhanced accuracy and reliability, became the recommended system to serve as the backup in the event of GPS failure due to jamming, random interference or outright hostile action. The recent demise of Loran-C, along with its anticipated progeny eLoran, raises the question whether all a marinerâ€™s navigational eggs are being tossed into the GPS basket and whether the Obama administrationâ€™s jettison of the only advanced radio-navigational aid that would be available in case of a GPS outage is prudent.
The 2010 Department of Homeland Security Appropriations Act (P.L. 111-83) Section 559, signed by the president in October 2009, directed the U.S. Coast Guard to discontinue Loran-C. This action was made contingent upon two requirements: (a) that the commandant of the Coast Guard certify that â€œtermination of the operation of the Loran-C signal will not adversely impact the safety of maritime navigationâ€ and (b) that the secretary of the Department of Homeland Security (DHS) certify â€œthat the Loran-C infrastructure is not needed as a backup to the GPS system or to meet any other federal navigation requirement.â€
The president dismissed Loran-A as â€œa long range navigation system which costs taxpayers $35 million a year. This system once made a lot of sense before there were satellites to help us navigate. Now thereâ€™s GPS and yet, year after year, this obsolete technology has continued to be funded even though it serves no government function and very few people are left who still actually use it.â€
One wonders why, if the system â€œonce made a lot of sense before there were satellites to help us navigate,â€ prudence would not dictate as backup a greatly improved version of the very system that once â€œmade a lot of sense,â€ given the possibility, if not probability, of future GPS interruption and/or failure.
As for â€œobsolete technology,â€ to contend that eLoranâ€™s up-to-date technology is â€œobsoleteâ€ is somewhat disingenuous. Perhaps â€œredundantâ€ instead of â€œobsoleteâ€ was the word intended, but even that would deny that eLoran utilizes advanced and totally dissimilar technology as backup for a critical system whose loss in a crisis could be catastrophic â€” redundant perhaps in protection, but not in method.
The act signed by the president in October included the â€œcontingenciesâ€ noted above. Yet six months earlier, a programmatic environmental impact statement (PEIS) dated June 1, 2009, noted that â€œthe Loran-C program had already been identified specifically for termination in the fiscal year 2010 proposed budget (www.regulations.gov (document 2007-28460), Page 23, line 31).
In a November 2009 letter to the DHS Secretary Janet Napolitano, Maine Sen. Susan Collins (ranking member of the Senate Homeland Security and Governmental Affairs Committee) called attention to the fact that an independent assessment team for the Institute for Defense Analyses, commissioned jointly by DHS and the Department of Transportation (DOT), came to the unanimous conclusion in January 2009 that â€œeLoran should serve as the national backup system for GPS and that the Loran-C infrastructure should be maintained until full eLoran deployment.â€
Note that the report was six months before the environmental impact statement and 10 months before the president signed the act â€œcontingent upon â€¦etc.â€
Sen. Collinsâ€™ letter also called attention to the DHS commitment to submit by July 30, 2009, the results of a survey of â€œ18 critical infrastructure sectorsâ€ as to whether a GPS backup was needed. As of November, it had not even been completed, much less submitted.
Could â€œcertificationsâ€ have been requested in order to provide the cover of a technical rationale in order to justify a political decision already made and in the process â€” to provide a post-facto imprimatur for a project for which budgetary support, according to the PEIS, had already been targeted for termination?
A study relating to GPS, Government Accountability Office report GAO-09-670T of May 7, 2009, (â€œSignificant Challenges in Sustaining and Upgrading Widely Used Capabilitiesâ€) contained the comments below, underscoring the downside of total reliance on one critical system:
â€œThe Global Positioning System (GPS), which provides position, navigation, and timing data to users worldwide, has become essential to U.S. national security and a key tool in an expanding array of public service and commercial applications at home and abroad.
â€œThe Air Force, which is responsible for GPS acquisition, is in the process of modernizing GPS. â€¦ It is uncertain whether (it) will be able to acquire new satellites in time to maintain current GPS service without interruption. If not, some military operations and some civilian users could be adversely affected. â€¦ there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number â€¦ required to provide the level of GPS service that the U.S. government commits to. â€¦ Such a gap in capability could have wide-ranging impacts on all GPS users.â€
Enhanced 911 services which rely on GPS for precise positioning as well as delay, cancellation or rerouting of commercial aircraft using predicted satellite geometry are but two civil functions that could well be jeopardized by lack of an accurate and immediately available backup system providing widespread coverage.
Not to be ignored are the findings that:
(a) About $160 million has already been invested in modernizing the Loran-C network, all in anticipation of full deployment of eLoran.
(b) The cost of deploying eLoran technology would be approximately the same as the cost of dismantling the current Loran infrastructure (a net loss by any standard).
(c) The cost of full deployment of eLoran would be about one-half the cost of placing one new GPS satellite in orbit.
(d) The administrationâ€™s own figures admit that to operate a system that would be the only highly accurate, reliable radio-navigation system in case of GPS interruption or failure would be just $35 million a year â€” the deployment of which was paid for by non-destruction of the infrastructure.
(e) A July â€™09 report (commissioned by both DHS and DOT) found that if, in 15 years there should be one â€œhigh-impactâ€ GPS outage, the benefits of having maintained eLoran would exceed the cost by a ratio of 13:1, a stunning finding, the disregarding of which defies logic.
A â€œWhite Paperâ€ prepared for the Federal Aviation Administration in August 2006 addressing â€œGPS Backup For Positioning, Navigation and Timingâ€ (PNT) concluded with the following:
â€œLoran is the lowest cost national technology that provides full PNT backup for GPS, well beyond just transportation. A backup for PNT is a national imperative that goes well beyond aviation and marine navigation. As a national critical infrastructure protection need, the public policy required to implement protection for GPS is a decision to continue Loran … and get standards in place for eLoran.â€
The decision to discard Loran rests on the assumptions that (a) GPS is inherently near 100 percent reliable, (b) that the extraordinarily expensive and technologically demanding satellite system will be maintained and (c) is fail-safe from intentional jamming, random interference or overt hostile destruction and that as a consequence of those assumptions, current navigational practice neither requires nor warrants a backup system using unrelated technology.
In the mid â€™50s, the chief quartermaster had guided yet another junior navigator through the fine points of Loran-A. Pointing to the scope, â€œthose notched, somewhat broad traces â€” most likely sky waves â€” for now weâ€™re after the ground waves. Double-check a fix using another method when available. You may lose the primary â€¦sometime it will happen â€¦ count on it.â€
About the Author:
Following graduation from the U.S. Naval Academy, Jim Austin served aboard both a destroyer and cruiser with duties that included navigator, assistant CIC (combat information center) officer and air intercept controller. He subsequently worked on the submarine launched ballistic missile program for the General Electric Co.â€™s Ordnance Division. He holds a U.S. Coast Guard masterâ€™s license and writes frequently on ship collisions as seen through the twin lenses of the navigation rules and maritime law. Heâ€™s a retired physician living in Burlington, Vt.