Originally Posted by
3rd_ear
I thought I'd drop this in here, rather than be flayed alive by the professionals elsewhere.
This morning, I was caught in a conversation in the street with a very non-geek woman and during this, observed two aircraft on the Heathrow S-bend flying rather closely together. I think it was a BA A380 (possibly flight BA282) ahead and about three 380 lengths behind and 500 feet above, an A320 or a 737 or something. The rear aircraft was heading maybe 5 degrees to stbd of the A380, crossing its wake. I was in N5 looking east, the aircraft were maybe over Stoke Newington (N16) at that point, time about 09:50 BST.
I said "kinell, that's a bit close" and she looked up and said " they're not supposed to fly together like ducks, are they?".
At what point does this kind of adjacency qualify as a "near-miss"? Doesn't an aircraft the size of an A380 leave rather a lot of turbulence in its wake? I really didn't fancy the look of what we saw there, but I had an idea that Heathrow were trying to squish a few more in and had reduced separation or something.
Any enlightenment gratefully received.
They do not try to " squish in a few more by reducing the separation". Ever ! This type of post, although not sensationalist in its tone, perfectly illustrates the ignorance of the man on the street. I do not mean to be offensive by using that word; it's just that the poster has no understanding of what is going on but does not let that lack of knowledge deter him from making a comment.
To answer the question. Anything less than 3nm horizontally between 2 a/c at the same level, or less than 1000 ft. Vertically within 3nm of each other , during the approach phase of the flight, is classed as a lack of separation ( or Airprox); & will be subject to possible investigation. The investigation will reveal the exact degree of lack of separation & the severity of the lack of separation.