FAA warns pilots in Las Vegas vicinity on GPS

[z987k]

I was flying in and around the 350nm of Las Vegas the past few months. I don't know if the tests were continuous or intermittent, but I never saw any problems with our gps system for photo work. My handheld on the other hand, has become a paperweight in the last few months. I don't even bother with it anymore. In fact... come to think of it, it only stopped pickup up a signal out west. Never had a problem in the midwest, Colorado, or SoCal, but in Vegas, Reno and Hawthorn it rarely got a signal. Wonder if that's a coincidence.

 

[RDoug]

Sounds to me as if the tests didn't go LightSquared's way . . . that they're delaying the results because of it. Also sounds as if the actual testing is over.

 

[ShyFlyer]

It is disappointing that LightSquared has misused its control of the study group process filing process to delay this filing.

That's a heck of sentence.

 

[RDoug]

It's official: Lightsquared failed their own tests.

 

[stesta5074]

No problems with GPS yesterday for me going into Vegas.

Plus, everyone from police, the fire department, and many public services actively use GPS. I'm confident they will get the hammer.

 

[skidz]

Interesting, if I get it right the company postponed testing for two weeks? High speed internet is a cool thing, but not at the expense of fliers.

 

[RDoug]

The latest on the Lightsquared tests:

http://www.bloomberg.com/news/2011-...needs-more-tests-witnesses-tell-congress.html

http://www.nextgov.com/nextgov/ng_20110623_8204.php?oref=topnews

 

[RDoug]

Lightsquared's original deployment plan now called, ". . . incompatible with aviation GPS operations.” Deployment would result in, ". . . a complete loss of GPS operations below 2,000 ft. above ground level over a large radius ” around many metropolitan areas.

 

[mshunter]

There is also disagreement over how long it would take to field new filters
for GPS receivers. “Based on past experience with programs for modification of
certified systems ... [aviation representatives believe this] would take at
least 8-10 years. LightSquared believes that the process could take
significantly less time,” based on past FAA actions “to address potential
unsafe conditions in far less time,” the report says.

So basically what Lightsquared is saying is that in the past, the FAA has made the industry pay for new equipment at a substantial cost, and they want aviation to do it again?

 

[SpiraMirabilis]

“Such a network would cause unacceptable interference to GPS operations, wiping out an installed base of over 500 million units used in a wide array of public safety, aviation, industrial and consumer applications,” the USGIC statement continued. “While mitigation techniques utilizing filters were discussed in theory, they could not be tested as part of the WG effort because filters do not exist, even in prototypes. No information considered by the WG demonstrated that any mitigation techniques – other than relocation of the proposed terrestrial network to an alternative band – would be successful.”

 

[inigo88]

Deployment would result in, ". . . a complete loss of GPS operations below 2,000 ft. above ground level over a large radius ” around many metropolitan areas.

The fact that this is even up for debate is absurd. Pilots aren't the only ones who use GPS below 2000 ft AGL. Think emergency responders: Police and Fire departments. Automatic vehicle location systems. The Department of Defense (the original reason the GPS constellation exists).

"Sorry we couldn't get there in time to save the life of your loved one. Here, enjoy this high speed internet."

 

[Autothrust Blue]

The fact that this is even up for debate is absurd. Pilots aren't the only ones who use GPS below 2000 ft AGL. Think emergency responders: Police and Fire departments. Automatic vehicle location systems. The Department of Defense (the original reason the GPS constellation exists).

"Sorry we couldn't get there in time to save the life of your loved one. Here, enjoy this high speed internet."

Amen.

Whatever they're smoking over there must be really potent stuff.

 

[SpiraMirabilis]

Amen.

Whatever they're smoking over there must be really potent stuff.

They're being petulant children when they realized that their bribes that got them the waiver from the FCC in the first place have been wasted. Except they can't come out and say that.

What I don't understand is they had to have at least one guy wearing glasses and a pocket protector working for them... he HAD to have known what was going to happen before they spent $1B+ on that satellite. This is the result of people discarding science and nerds.

 

[Homa Bird]

CIA conspiracy



lol jk don't bombard me with lecture

 

[fatcat]

Keep in mind that telecommunication services (cellular phone towers, base stations, central offices) rely upon GPS for sync'ing time. They usually have some GPS antenna on the roof of such facilities. Without GPS, their clocks drift and they'll have issues with managing the RF spectrum as well as hauling bits out of them. Basically, calls wont work.

 

[inigo88]

Keep in mind that telecommunication services (cellular phone towers, base stations, central offices) rely upon GPS for sync'ing time. They usually have some GPS antenna on the roof of such facilities. Without GPS, their clocks drift and they'll have issues with managing the RF spectrum as well as hauling bits out of them. Basically, calls wont work.

EXCELLENT POST!!! I totally overlooked the fact that you can't do simulcasting the way it's done now without GPS! To everyone not familiar with radio/RF engineering/ham radio geekery, simulcasting is when you want to cover a target geographic area with multiple radio towers spread around the area all transmitting simultaneously. The problem is that even though radio waves travel at the speed of light, the signal from the closer tower is still going to reach you in the target area a little bit faster than the signal from a more distant tower (even though the difference may only be a couple thousandths of a second). The two out of phase radio waves conflict and it ends up sounding like crap, so RF engineers try and get them all to arrive on target at exactly the same time if possible. You can't make the more distant waves travel faster than the speed of light, but you CAN delay the ones from the closer towers, so that when they start traveling towards you the waves from the more distant towers were already in transit and they're all the same distance away from you.

The problem is, in order to control such a minuscule delay time all the towers need their clocks exactly synchronized to one another. The solution is to synch them all up with the precision clock on a GPS satellite, so the individual delays can be set relative to a constant baseline time. I hope I didn't butcher that explanation too badly.

This is an incredible irony, that out of incompetence and greed the FCC would humor a proposal by a company which would effectively destroy the rest of industry the FCC is responsible for regulating.

Whoops!!!

 

[RDoug]

Lightsquared is at it again with a revised proposal.

"On June 20, LightSquared offered a new plan that it said wouldn't interfere with the vast majority of GPS systems. It would use just the portion of its frequencies that are farthest away from GPS signals and would transmit weaker signals. Even with those changes, LightSquared's network could still affect some precision GPS systems, which are generally used by farmers, the aviation industry and others."

 

[Autothrust Blue]

Shut it down.

 

[Apophis]

Why are they continuing to be allowed to do this? Who the hell at LightSquared is in bed with the FCC? Somebody has to be, there's no reason a regulatory agency like the FCC should have granted their proposal so quickly, without extensive testing first.

I'd imagine this proposal will also be turned down; at least I hope it is.

 

[RDoug]

I got a laugh out of Lightsquared's position. Basically, they're saying, "The FAA should have no problems with this because we've addressed the concerns of almost everybody except the FAA."