Separation
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Separation
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.
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.
Last edited by 3rd_ear; 31st Aug 2016 at 10:17. Reason: typo
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Without knowing the situation, I'd be astounded if they weren't 1000ft apart.
Have a look at FlightRadar24.com or Heathrow's own webtrak and you can rewind to watch. While altitudes as absolute values may not be 100% accurate, the relative separation should be.
Have a look at FlightRadar24.com or Heathrow's own webtrak and you can rewind to watch. While altitudes as absolute values may not be 100% accurate, the relative separation should be.
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BAW282 + BAW885 were at all times 1500ft separation, then on approach it reduces to 1000ft difference. Although 282 was for 27R and 885 for 27L. Definitely no where near a near miss
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Yes, finally worked out Webtrak - there was 1900 ft vertical between them, not an awful lot horizontal. The A380 is so big (and so A319 proportioned!), it's difficult to scale between it and other aircraft.
Still, there was lots of empty sky all around, no need to frighten the natives with antics, so I'd prefer it if they didn't get quite so close
Still, there was lots of empty sky all around, no need to frighten the natives with antics, so I'd prefer it if they didn't get quite so close
The A388 was off the Bovingdon hold, and it turned inside the A321 (off Lambourne) for 27R and 27L, respectively, as mentioned above.
At their point of closest approach (about 200m horizontally) there was around 1800' of vertical separation (give or take - WebTrak rounds heights to 100').
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.
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.
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.
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Still, there was lots of empty sky all around, no need to frighten the natives with antics, so I'd prefer it if they didn't get quite so close
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There is no reason to be uncivil - or arrogant.
I think it's perfectly fair to wonder why two aircraft are vectored like that when there is evidently room not to. Is there not an issue with wingtip vortices from "heavies"? How much vertical and horizontal clearance is needed for a following aircraft to avoid these? I have heard pilots in the past on 120.4 comment on turbulence as a consequence of following a 747 down the glideslope into Heathrow, so I'd have thought an A380 would get quite a bit of elbow room on the way in.
I clearly have *some* understanding of what is going on - my "squish" comment comes from a vague memory of something changing, which was actually the 3.2 degree slope trial to do with noise rather than capacity.
I think it's perfectly fair to wonder why two aircraft are vectored like that when there is evidently room not to. Is there not an issue with wingtip vortices from "heavies"? How much vertical and horizontal clearance is needed for a following aircraft to avoid these? I have heard pilots in the past on 120.4 comment on turbulence as a consequence of following a 747 down the glideslope into Heathrow, so I'd have thought an A380 would get quite a bit of elbow room on the way in.
I clearly have *some* understanding of what is going on - my "squish" comment comes from a vague memory of something changing, which was actually the 3.2 degree slope trial to do with noise rather than capacity.
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3rd ear. With great respect it is abundantly clear that you have little or no understanding of how ATC works. Separation for wake turbulence is applied rigorously by ATC at all stages of flight but it can still occasionally cause problems. I worked on 120.4 for 30+ years and I can assure you that such problems are not common.
We have been assured that there was 1700ft vertical separation between the aircraft, which was more than the minimum required.
I assure you that the controllers are highly trained and they know what they are doing. It is almost impossible to estimate altitudes or ranges from other aircraft from the ground so please accept that there was no danger to anyone.
We have been assured that there was 1700ft vertical separation between the aircraft, which was more than the minimum required.
I assure you that the controllers are highly trained and they know what they are doing. It is almost impossible to estimate altitudes or ranges from other aircraft from the ground so please accept that there was no danger to anyone.
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Thanks for your input, everyone.
I've always been impressed by ATC, especially when the Heathrow "floodgates" open at 06:00 (always sounds frantically busy in a calm sort of way) and I thank you for the reassurances.
I'm not sure a telly programme would help me, not owning such a device, but a "fly on the wall" documentary about ATC would probably make rivetting viewing for those that do.
I've always been impressed by ATC, especially when the Heathrow "floodgates" open at 06:00 (always sounds frantically busy in a calm sort of way) and I thank you for the reassurances.
I'm not sure a telly programme would help me, not owning such a device, but a "fly on the wall" documentary about ATC would probably make rivetting viewing for those that do.
I'd prefer it if they didn't get quite so close
Here is a question from a complete novice for the experts.
Is wake turbulence from an aircraft confined to its altitude or does it propagate up or down? If I am in, say, an A319 and an A380 passes 1,000 feet above or below would I suspect to encounter turbulence?
Is wake turbulence from an aircraft confined to its altitude or does it propagate up or down? If I am in, say, an A319 and an A380 passes 1,000 feet above or below would I suspect to encounter turbulence?
That's funny, only a few days ago I was watching an A380 coming into LHR and watched a G5 or GLEX cross over it heading into RAF Northolt and wondered to myself if there would be any wake turbulence felt by the roughly 1000ft higher biz jet ? Obviously not the same as flying/crossing directly behind the behemoth, but none the less would tree be any noticeable effects ?
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There is no requirement for ATC to provide additional separation in the example you mentioned. Northolt traffic overflies Heathrow inbounds frequently with 1000 ft vertical separation. Internationally agreed separation standards are applied at all stages of flight.
There is no reason to be uncivil - or arrogant.
I think it's perfectly fair to wonder why two aircraft are vectored like that when there is evidently room not to. Is there not an issue with wingtip vortices from "heavies"? How much vertical and horizontal clearance is needed for a following aircraft to avoid these? I have heard pilots in the past on 120.4 comment on turbulence as a consequence of following a 747 down the glideslope into Heathrow, so I'd have thought an A380 would get quite a bit of elbow room on the way in.
I think it's perfectly fair to wonder why two aircraft are vectored like that when there is evidently room not to. Is there not an issue with wingtip vortices from "heavies"? How much vertical and horizontal clearance is needed for a following aircraft to avoid these? I have heard pilots in the past on 120.4 comment on turbulence as a consequence of following a 747 down the glideslope into Heathrow, so I'd have thought an A380 would get quite a bit of elbow room on the way in.
By the way 3rd_ear, it is statements such as bolded below that tend to cause derision from the professionals on the message board.
See, you have no way of knowing what the vertical separation between the aircraft is. If you'd worded your question in a less authoritative manner then the response would be much more gentle.
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.