Near mid-air collision ?
Jan 4, 2015 | 3:46 am
#1
Original Poster
Join Date: Dec 2009
Posts: 557
Near mid-air collision ?
I was tracking KL597 with Planefinder but I got scared for a midair collision with 500+ killed. I saw this flight approach
Vueling 6630 at about the same altitude and later to AZ630, also at FL330. Strange, the latter one is flying westward so it should have an even FL such as FL320 or FL340.
Is this really a safety or ATC incident ?
Vueling 6630 at about the same altitude and later to AZ630, also at FL330. Strange, the latter one is flying westward so it should have an even FL such as FL320 or FL340.
Is this really a safety or ATC incident ?
Jan 4, 2015 | 9:28 am
#2
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Without any scale, it's impossible to know how far apart these are. I'm relatively confident the plane icon and distances aren't to scale.
If I had to bet, I'd bet they were meeting separation guidelines.
If I had to bet, I'd bet they were meeting separation guidelines.
Jan 4, 2015 | 9:38 am
#4
Join Date: Aug 2004
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Sweet find OP!
Speed is the last trim you'd use at cruise with a given weight and altitude as it'd require you to change the angle of attack. You'd try to change direction or altitude first outside of a pattern.
Speed is the last trim you'd use at cruise with a given weight and altitude as it'd require you to change the angle of attack. You'd try to change direction or altitude first outside of a pattern.
Jan 4, 2015 | 11:21 am
#5
Join Date: Feb 2013
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Near mid-air collision ?
Maybe it is, but it doesn't stop the data clearly showing that the Alitalia aircraft is travelling more slowly...considerably below normal cruise speed.
Jan 4, 2015 | 11:37 am
#6
Join Date: Mar 2012
Posts: 536
Speed shown is ground speed and it does not require unusual headwind to slow the ground speed below 800kph in normal cruise. Note that Vueling going to same direction has even lower speed. And if there was a collision risk, which I very much doubt, it was between VY6613 and KL597 as 100 feet is nowhere near minimum vertical separation. However I believe the scale in the picture is so large that there was no danger.
Jan 4, 2015 | 1:32 pm
#8
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Zooming Plane Finder in to the largest scale at which individual aircraft altitude and speed are shown, and using EarthTools for scaling, the planes could be as far as 8+ miles apart.
It could be closer, depending on how far you are zoomed in. But given this data, I remain fairly confident that a deadly collision was not imminent.
EDIT: I also tracked a specific flight over my house for a few minutes, watching Plane Finder and flightware update the data on a minute-by-minute basis. Several times the flight jumped 20-50 miles from the last projected location to the new updated location. The Plane Finder location details are nowhere near detailed/accurate enough to interpret separation distances, IMHO.
It could be closer, depending on how far you are zoomed in. But given this data, I remain fairly confident that a deadly collision was not imminent.
EDIT: I also tracked a specific flight over my house for a few minutes, watching Plane Finder and flightware update the data on a minute-by-minute basis. Several times the flight jumped 20-50 miles from the last projected location to the new updated location. The Plane Finder location details are nowhere near detailed/accurate enough to interpret separation distances, IMHO.
Last edited by CPRich; Jan 4, 2015 at 1:48 pm
Jan 4, 2015 | 3:19 pm
#9
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Before worrying about a potential loss of required separation here, one has to: 1) know the accuracy of planefinder's altitude data, 2) the "refresh" rate: how often the site "refreshes" position data of aircraft; and, very importantly, 3) the scale or range shown.
In the U.S., aircraft at cruise at these altitudes, must be separated by at least five miles horizontally if at the same altitude (or less than 1,000 feet difference vertically). There's only a loss of required separation if the distance of same altitude traffic from each other goes below five miles.
In the U.S., aircraft at cruise at these altitudes, must be separated by at least five miles horizontally if at the same altitude (or less than 1,000 feet difference vertically). There's only a loss of required separation if the distance of same altitude traffic from each other goes below five miles.
Jan 4, 2015 | 5:38 pm
#10
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Jan 5, 2015 | 3:24 pm
#11
Join Date: Dec 2010
Posts: 363
Near mid-air collision ?
This is typical fb generation. You think that everything online is true. There are so many unknown parameters to the data displayed, so lets not rely on flight tracker to ensure separation.
I am confident ATC and the aircraft itself manage the situation in a safe and reliable manner.
I am confident ATC and the aircraft itself manage the situation in a safe and reliable manner.