Results 1 to 9 of 9

Thread: How often do airliner near misses happen over the Atlantic?

  1. #1
    Passenger
    Join Date
    Feb 2019
    Posts
    4

    How often do airliner near misses happen over the Atlantic?

    Last time I flew, on August 11 last year, I was on Norwegian Air Gatwick to Denver DI7171. Daytime flight.
    About half way over I was startled to see a green and white plane that I have since tracked down via this site to be the Aer Lingus return flight EI144 from LAX to Dublin. It was visible over the starboard wing, flying in the exact opposite direction to us.
    What startled me was the lack of height difference between us. I am not experienced in visual judgement of distances. Its horizontal distance was obviously something within a mile. It was only visible through the porthole for less that 3 seconds.
    According to FR24 records on Aug 11 its height should have been 39K and ours was 38K. It would be futile to try to convince an expert that the height separation was insufficient, all I can say is that 1000 feet is about 5 times the length of the Airbus 330 and this plane seemed significantly less than five times its length in height separation.
    I just wondered if anyone had any comment?

    I tried to attach an image, not of the actual incident but a fairly comparable image of a plane at a similar elevation, but this is my first post and I don't think I am allowed yet.
    Attached Images Attached Images

  2. #2
    Super Moderator
    Join Date
    May 2011
    Location
    T-NZCH1, PP:PH New Zealand
    Posts
    4,957
    https://en.m.wikipedia.org/wiki/Redu...aration_minima

    Sent from my EML-L09 using Tapatalk
    Posts not to be taken as official support representation - Just a helpful uploader who tinkers

  3. #3
    First officer
    Join Date
    Dec 2014
    Posts
    221
    The clear dry air at altitude makes things look rather different. Even with pre-RVSM 2000ft separation, aircraft look close to the untrained eye. It can be even more disconcerting from the flightdeck, as due to the curvature of the earth, an aircraft approaching head on and above you may appear to be beneath you when first sighted.

  4. #4
    Passenger
    Join Date
    Feb 2019
    Posts
    4
    Thanks, I didn't even realise that it used to be 2000 ft.

  5. #5
    First officer
    Join Date
    Dec 2014
    Posts
    221
    Quote Originally Posted by jiver View Post
    Thanks, I didn't even realise that it used to be 2000 ft.
    The introduction of RVSM and 1000 ft separation in the prime FL310 to FL410 jet levels resulted in a huge increase in airspace capacity over the previous 2000ft levels and not just over the Atlantic.

  6. #6
    Passenger
    Join Date
    Feb 2019
    Posts
    4
    OK, and if another airliner was approaching head on at the wrong height and within the 1000 ft 3 mile box, how would the pilot know?

  7. #7
    Super Moderator
    Join Date
    May 2011
    Location
    T-NZCH1, PP:PH New Zealand
    Posts
    4,957
    Quote Originally Posted by jiver View Post
    OK, and if another airliner was approaching head on at the wrong height and within the 1000 ft 3 mile box, how would the pilot know?
    Computer infront of ATC controller would realise proximity/collision alert well before

    And onboard TCAS https://en.wikipedia.org/wiki/Traffi...oidance_system would trigger using the same ADSB signal used to display on the web
    Posts not to be taken as official support representation - Just a helpful uploader who tinkers

  8. #8
    First officer
    Join Date
    Dec 2014
    Posts
    221
    Quote Originally Posted by jiver View Post
    OK, and if another airliner was approaching head on at the wrong height and within the 1000 ft 3 mile box, how would the pilot know?
    As mentioned, aircraft are fitted with TCAS (Traffic Collision Avoidance System) which picks up signals from adjacent aircraft and then provides the pilot with traffic information, including ultimately calculating and showing a safe avoidance path (Resolution Advisory RA). I'm not sure what the 3 miles you mention refer to, unless you refer to the terminal area radar separation standard. The lateral separation distance over the Atlantic is a fair bit more than that as it is non-radar airspace. The software used for oceanic sectors will generate warnings if a conflict is identified, but that is based on HF radio and ADS satellite reports which would not be timely enough to identify if an aircraft suddenly drifted from his cleared level or track.

  9. #9
    Passenger
    Join Date
    Feb 2019
    Posts
    4
    OK, thanks all

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •