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Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

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Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#161

Post by sokoloff »

boarnoah wrote: post #159
cbanek wrote: post #154

Earlier quoted context omitted.

Are they also getting rid of VOR for navigation? https://en.wikipedia.org/wiki/VHF_omnidirectional_range (Sorry, paywall is blocking me)

Not too familiar with aviation or IFR. Isn't VOR primarily a beacon that you use to orient yourself, doesn't seem like it helps the ATC maintain separation etc..

IFR separation does not have to depend on radar. Though radar procedures are the norm, there are non-radar procedures wherein ATC can issue instructions (clearances) that provide separation for airplanes who are all navigating themselves with respect to ground-based or satellite fixes. In that regard, VORs help ATC maintain separation.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#162

Post by toomanybeersies »

iudqnolq wrote: post #160
Patrick_Devine wrote: post #109

Earlier quoted context omitted.

The problem with _requiring_ authentication is that it can create a safety issue when communications break down. As a pilot it's not a bad idea to carry a spare handheld radio, or even use a cel phone, when you lose communications. I was flying once with a buddy of mine who was Pilot-In-Command and we lost (or thought we had lost) our radio on an IFR flight back into the Bay Area. What had happened was the Push-to-Ta…

Dumb question: how would a cellphone work given they don't work on passenger aircraft?

General aviation flies a lot lower and slower than passenger jets.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#163

Post by lutorm »

danaliv wrote: post #130
code4tee wrote: post #14

Radar isn’t going away. This article talks as if ADS-B is replacing radar, which it’s not. It’s enhancing radar where radar coverage exists and providing coverage on traffic where radar coverage currently does not exist (usually lower altitudes away from major airports and over the ocean).

Indeed. Not everyone even has to have ADS-B Out. You only need it if you’re going into or over Class C or B airspace, in the Class B veils, Class E above 10,000 except below 2500 AGL, and in Class E over the Gulf of Mexico. That leaves huge swathes of airspace—dare I say most airspace in the US—where ADS-B isn’t required. You could fly across the entire country without hitting an ADS-B requirement. And the only way f…

Except that is also the same airspace where ATC doesn't have to see you. You don't even need a transponder to fly in those areas.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#164

Post by sokoloff »

redis_mlc wrote: post #146
jrockway wrote: post #67

A lot of comments seem to be about spoofing. Remember that there are multiple humans in the loop -- experienced pilots and experienced air traffic controllers -- and multiple levels of redundancy. Pilots have access to barometric altitude, radar altitude, traditional VHF navaids, TCAS-issued resolution advisories (based on directional antennas, not GPS)... in addition to GPS. Air traffic controllers have primary rada…

> Air traffic controllers have primary radar and secondary radar in addition to ADS-B information. No they don't. Most secondary (surveillance) radar in the US has been shut down already. The FAA has been busy shutting down basically anything that requires maintenance, and LORAN is gone too. I believe the whole point of ADS-B out was to shut down basically the rest. Source: commercially-rated pilot.

Secondary radar is very much alive in the US. Forget to turn on your transponder (whether or not you are ADS-B out equipped) and how long until ATC notices? For me, it's usually been before I'm through 400' AGL. Or, as tjohns mentions, just look at how often your reply light flashes.

From the FAA itself: "The Mode S SLEP Phase 2 program will implement modifications to the Mode S system to sustain secondary surveillance service through 2028."

0 - https://www.faa.gov/air_traffic/publications/cip/files/FY16-...

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#165

Post by lutorm »

code4tee wrote: post #14

Radar isn’t going away. This article talks as if ADS-B is replacing radar, which it’s not. It’s enhancing radar where radar coverage exists and providing coverage on traffic where radar coverage currently does not exist (usually lower altitudes away from major airports and over the ocean).

I was under the impression that one of the main drivers of ADS-B is to enable smaller separation between aircraft due to the more accurate position reporting. If that's the case, then radar won't be a useful backup because planes would be closer than the radar can separate them.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#166

Post by sokoloff »

toomanybeersies wrote: post #162
iudqnolq wrote: post #160

Earlier quoted context omitted.

Dumb question: how would a cellphone work given they don't work on passenger aircraft?

General aviation flies a lot lower and slower than passenger jets.

I've found that unless I'm under about 10000' and under about 150 knots, cell phones don't work very well in GA either.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#167

Post by sokoloff »

lutorm wrote: post #165
code4tee wrote: post #14

Radar isn’t going away. This article talks as if ADS-B is replacing radar, which it’s not. It’s enhancing radar where radar coverage exists and providing coverage on traffic where radar coverage currently does not exist (usually lower altitudes away from major airports and over the ocean).

I was under the impression that one of the main drivers of ADS-B is to enable smaller separation between aircraft due to the more accurate position reporting. If that's the case, then radar won't be a useful backup because planes would be closer than the radar can separate them.

Planes under IFR will be as close as ATC policies want to run them. If everything's working and separation standards become 2nm laterally, then when there's a GPS or ADS-B outage, we can just revert to the 5nm separation standards and use radar backup.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#168

Post by tjohns »

cbanek wrote: post #154
wrycoder wrote: post #149

Earlier quoted context omitted.

If you shut it all down and something catastrophic somehow goes wrong with GPS, it will be very difficult to get the thousands of planes in the air back onto runways.

Are they also getting rid of VOR for navigation? https://en.wikipedia.org/wiki/VHF_omnidirectional_range (Sorry, paywall is blocking me)

VOR navigation is very much still a thing.

They've been reducing the number of redundant ground stations lately as part of a project called "Minimum Operational Network", or "MON". (Mostly on affecting the east coast.) But they're explicitly making sure there's enough coverage that you can get a VOR signal anywhere above 5,000 feet AGL.

More info: https://www.faa.gov/about/office_org/headquarters_offices/at...

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#169

Post by FabHK »

sokoloff wrote: post #166
toomanybeersies wrote: post #162

Earlier quoted context omitted.

General aviation flies a lot lower and slower than passenger jets.

I've found that unless I'm under about 10000' and under about 150 knots, cell phones don't work very well in GA either.

Nice plane you have, if you fly above 10000' or above 150 knots frequently :-)

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#170

Post by FabHK »

Patrick_Devine wrote: post #145
danaliv wrote: post #129

Earlier quoted context omitted.

Seven six, on the fritz! (Squawk 7600.) There’s an established, cut—and-dry procedure for when an IFR aircraft goes NORDO. Even without that handheld, you would’ve been fine. Every airplane between you and your destination, on the other hand, would find themselves being rerouted.

I didn't mean to imply that we thought we were in any kind of imminent danger. There were three pilots (including myself) in the plane, all whom had trained in a highly congested area. My point was that having the handheld radio allowed us to trouble shoot the situation. Without the radio there would have been a lot higher workload and less of a margin for safety.

Plus you might've inadvertently blocked the frequency longer (for other participants) if you hadn't been able to diagnose it. So it was definitely a good thing you had the handheld aboard: even if there was no imminent danger for you, it would have been an inconvenience for many.
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