USCG Loran shut down comments, worth making
I still maintain that shutting down the Loran system is a red herring, but the USCG has asked for comments on the subject, and hands are wringing. Here, for instance, is a short piece called “Loran’s Last Chance?” on AVweb. Follow the link where the author writes “The UK has a similar [Loran] system and is also pondering whether to keep it or not”. Not really, you’ll find; what the Brits are actually thinking about is building a new eLoran system!
Nonetheless, it seems prudent for any one who wants a redundant electronic positioning system—and you should!—to register their opinion. And the government has made it easy (though not so easy to give you full links). Here’s the drill: go to http://dms.dot.gov and do a simple search for docket item 24685. You should get to the screen above, which gives you access to the Notice itself plus the comments coming in. Unfortunately the TXT versions don’t word wrap, but the PDFs read fine. Try Robert Gardner’s for some good dope, and I’m hoping my own comment, submitted early this morning, will go up soon. Comment Submissions, button at top above, is a really easy form, and very little ID is required. (Nice work, DOT!)
For more info on Loran, the Wikipedia entry is excellent, and it also got me to an amazing PhD dissertation on the subject just completed by Wouter Pelgrum. He’s the guy who got dizzy on a Massachusetts clover leaf demonstrating how accurate even the somewhat improved current Loran system can be. Now, I’m going to do more testing on the Si-Tex eLoran, already looking good; you think about telling the USCG that we need this capability.
** Reprint from Aero-News Network **
AOPA Says Loran May Take On New Life In Age Of GPS
Mon, 10 Sep '07
Notes Satellite-Based Nav Still Has Its Problems
GPS isn't perfect... and during outages pilots need a suitable backup. The Aircraft Owners and Pilots Association says while most pilots use VORs, the FAA plans to decommission them in the next 15 to 20 years.
Enter loran... or should we say, reenter loran.
Last year, the Coast Guard, which operates and maintains loran transmitting stations, proposed to pull the plug on this technology. AOPA pointed out that it still may need to play an important role in the nation's navigation and airspace surveillance system. The Coast Guard then decided to take a more studied approach.
But recently, the Coast Guard asked users to weigh in on its future. If it's retained, the Coast Guard listed options on how to manage it. Loran was more popular until GPS came along. GPS has proven to be easier to use and more affordable for primary navigation.
"It's premature to talk about management options until the FAA and Coast Guard decide if loran is suitable for aviation use as a backup to GPS," said Randy Kenagy, AOPA senior director of advanced technology. "We can discuss how to manage it later."
Over the next two decades, the FAA plans to decommission VORs and radar systems and make the transition to ADS-B (automatic dependent surveillance-broadcast) as the primary surveillance system for air traffic control. Because ADS-B requires GPS to report an aircraft's position to ATC, a GPS failure could leave pilots without electronic navigation and air traffic controllers blind unless an alternative positioning system were available.
In its recent comments to the Coast Guard, AOPA laid out various performance parameters for a backup system such as being available for instrument operations throughout North America and the Caribbean; providing uninterrupted service for 30 minutes after a GPS outage; and adding no more than 10 percent to the cost of a navigation or dependent surveillance system.
"While loran appears to be a viable option—among other options—many questions and policy issues remain," Kenagy said. "Those would have to be resolved before the FAA, Coast Guard, and the aviation industry can develop an implementation strategy."