Air Traffic Control
Hello, world. It's been a while.
Politics just got too exhausting, especially as nothing ever seems to change.
But this morning I was listening to NPR, and they had an article on the “next generation” air traffic control system, the contract for which has just been awarded, and I wanted to make an observation.
This new system will reportedly work not based on “outdated” RADAR technology, but on GPS. This is reportedly far more accurate and will allow planes to safely operate more closely to each other in the sky, as our number of daily travelers grows ever higher.
Sounds good, so far as it goes. And hopefully the people who will develop this new system have already considered what I'm about to suggest...
What happens if the GPS system fails? I don't mean necessarily catastrophically, I mean even simply. I've been out with my GPS (granted a much more inexpensive model than one would assume would be on a jumbo jet, but still) and, on a clear day with no trees around lost my contact with the satellites. There are intermittent outages. And most importantly, all of our electronics in low earth orbit are subject to down time or outright failure when there is high sun-spot or solar flare activity.
So what happens on the day that our sun gets a bit restless, has a bad case of gas, and breaks wind in our direction? What happens when all of those planes, more closely packed in the sky and relying absolutely on their knowledge of each others' relative positions, suddenly lose their GPS signals?
I'm quite sure in a multi-billion dollar system that's being developed, there will be some kind of backup system, right? And I can't be the only person to have had this thought while listening to the reporter extolling the virtues of GPS and the marvels it will bring to modern air travel, right?
The system is scheduled to be developed over the next 15-20 years, there's plenty of time for people to find and fix all of these issues.
But it was the first thing through my mind when I heard the story, and since I can't get it out of my head, maybe writing about it will help.
Liam.
Labels: News
posted by Liam at 8/30/2007 10:30:00 PM
3 Comments:
(Here's the response you were expecting. :-) )
There seems to be a sufficiency of information about ATC plans here Right at the top today I see an article headlined Major Contract Awarded to Build ADS-B, A Prime NextGen Initiative. It states:
"One of NextGen’s most promising initiatives with potential for broad operational applications is Automatic Dependent Surveillance-Broadcast (ADS-B) .... ADS-B uses GPS satellites and ground-based equipment to allow aircraft to broadcast their transmissions with greater frequency and accuracy than the current land-based legacy radar systems."
So firstly, it implies that even without a visible GPS beacon (or enough beacons) the plane can still get information about its position from land-based beacons. An older system called LORAN worked for close-to-harbor boat navigation a few decades ago, using land-based beacons to automatically triangulate your position.
It would seem logical that such land-based beacons would be much thicker where traffic is thicker, near airports and near heavily used corridors. So that helps too.
Next thing I would point you at is this paragraph here, in the document http://www.jpdo.gov/library/NextGen_v2.0.pdf:
"1.2.2.8 Robustness and Resiliency Overall, NextGen is more resilient in responding to failures and disruptions and includes contingency measures to provide maximum continuity of service, including business continuity, in the face of major outages, natural disasters, security threats, or other unusual circumstances. Moreover, the increased reliance on automation is coupled with “fail-safe” modes that do not
require full reliance on human cognition as a backup for automation failures. Because individual systems and system components can fail, NextGen maintains a balance of reliability, redundancy, and procedural backups. It provides a system that not only has high availability but also requires minimal time to restore failed functionality."
Not that this should calm your nerves completely, of course, but maybe it's a starting point to look further.
Tuesday, September 04, 2007 3:33:00 PM
All of which goes to show the extent to which this blog has sunk. There was a day when I wouldn't have asked the question without doing some of the research Ross did above.
Instead, I heard one little NPR report on the new system and decided to post my rabble rousing.
That'll learn ya. If y'er lookin' fer quality bloggin', look elsewhere. :-)
Liam.
P.S. Thanks, Ross!
Tuesday, September 04, 2007 6:12:00 PM
Backup bloggers as well as backup beacons? :-)
Notice that I myself don't count as one, since I only do research *after* reading someone's blog.
Wednesday, September 05, 2007 10:10:00 AM
Post a Comment
<< Home