AS380 separations released by UK CAA

[headsethair]

Get the pdf here (http://www.caa.co.uk/application.aspx?categoryid=33&pagetype=65&applicationid=11&mode=detail&id=2110)

[CamelhAir]

10 miles on final? So taking up the space of 2 747's thus less passengers per 10 miles. Sounds like the answer to airport congestion. Not.

[lord Montford]

What about holding? Do i understand correctly that there should be 1500ft min between an A380 and another a/c below it in the hold? If so we loose an additional level in the stack if one A380 is holding (god help us if there is more than one A380 in the hold). And how about reciprocal traffic? am i to be vectored miles out of the way of an A380 when i am heading north up the bay of biscay at FL360 and an A380 is heading south at FL370?

[Daysleeper]

Its just ICAO advanced standard, Airbus will undoubtedly be appealing against this spacing and are supposed to be doing comparative trials at Istres this year with a A319, A340, 747 and 777 as well as the whale.

[Max Angle]

Crossing the path of an A380 that has past a 1000ft above is also going to be interesting. I have had several scary encounters with 747 wakes when the traffic has passed accross our track about 20nm ahead 1000ft above. By the time you get there a few minutes later the wake has sunk 1000ft and you run right into it. Not nice.

[sarah737]

Took off from Toulouse in a 737, 2 minutes behind the A380, on one of its first flights, no wake at all...

[ATC Watcher]

Be careful with drawing too many conclusions, these are precautionary measures , similar to those taken in 1968-69 when the 747 was being test flown , for those old enough to remember, ( gosh ! age shows :uhoh: )

These value apply to the 3 prototypes being currently flowm , and as Daysleeper said, the current tests in Istres will be interesting to watch.
I was told Airbus believes the A380 behaves better than the 777 and has chartered one from AF to compare.

[Spitoon]

Took off from Toulouse in a 737, 2 minutes behind the A380, on one of its first flights, no wake at all...Well if the 380 is anything like a 340 you'll have outclimbed it easily in your 737!!!

[notdavegorman]

.....and? A lightly loaded s/haul twin (sarah737 from the UK, flying from TOU probably to the UK) will ALWAYS out climb a l/h aircraft (assuming the l/h aircraft is being used for what it's designed for), whether it's an A340, A380 or any of Boeing's bigger products for that matter. To paraphrase Rodney Marsh, what's your point?

[KLMer]

Some of you guys make very valid points and other of you seem to be going off the beaten track. None of us are experts at wake vortex nor should even try to be but we can go on your experiences. One example i can think of is lets look at the vortex seperation differences between the 757 and the A321 same size aircraft yet different catagory in the UK. could this be down to new technology and not just weight.

Come on guys why do us brits always slagg of new technology especially when were invloved in producing it.

[ukatco_535]

I work in the London TMA, believe me, if that is the separation required, then we are scr*&*d. Our job is hard enough.

Point of note

These are NOT the final wake vortex spacing requirements, they are the temporary ones until further testing is done, which is, I believe, in March.

The A380 will be at Farnborough 2006... if that is the spacing that is required, it will not be flying - the temporary restricted airspace is already a big enough headache to us when controlling Heathrow SIDS... I can't see anything being allowed to depart if the A380 is displaying at EGLF

[KLMer]

Correct me if im wrong but is wake votex weight related as well as the aircraft cat, the A380 when it desplays must be lighter than a A340 full of pax so what the prob.

[Andy_S]

Since when have an A321 and B757 been the same size?

[GOLF-INDIA BRAVO]

B757 200 is 9ft longer and has a wingspan of 13ft extra but the vortex on a B757 is a lot more, on a calm day when a B757 passes over the house which is 4 miles from the threshold you can hear and feel the vortex in the garden

G-I-B

[cavortingcheetah]

:confused:

Forgive me here because I know little of matters vortical.
However, from personal experience I am not convinced that vortex wake is entirely related to aircraft weight.
In my cowboy days we often used to land rather close behind big jets taking off. There was never usually a problem and we laughingly went upon our merry way. Until the day that is when we tried the trick behind a 757 departing Edinburgh. That was very, very, nearly a nasty whoopsie and the cavalier attitude was banished thenceforth, back to the little shelf where all such attitudes belong in the great saga that is aviation.
I looked long and hard at the anhedral of the 757 after that little mishap and came to the conclusion that wake turbulence, for any given set of meteorological circumstances, for example, is not so much a function of weight as it is of aircraft design. If this be the case, then of course wind tunnel testing in the development stages of an aircraft should surely reveal the hidden menace?:ooh:

[GOLF-INDIA BRAVO]

A very good way of judging it is to stand under the landing lights and from memory the B757 and Concorde seemed to be way stronger than anything else

G-I-B

[KLMer]

Thanks your your post G-I-B and CAVORTINGCHEETAH what is was i trying to suggest about the A321 and the B757 but you have put it across in a better way it seems that Andy S missed my point, so give or take the A321 and the B757 are the same size but produce greatly different vortex tendencys.

Lets hope the A380 is not as bad as we all think as new technology should help reduce these nasty little blighters !!

[balsa model]

Pardon my lack of formal education in this matter but I seem to recall that vortex comes from the need for lift.

Hence:
- the heavier, the more vortex
- the shorter the wings, the more vortex (with less air mass/sec to swirl, it has to swirl harder)
- the slower, the more vortex (same reason as above)

Could the landing/takoff speed difference between A320 and B757 account for the above observations? Is B757 approach slower?
(Just curious and trying to make sense of aerodynamic questions in general.)

[podbreak]

In Australia wake vortex seperation is determined by weight category, with the exception of the 757 and chinook. A321 has no such exemption. It seems the 757 is unusually nasty.:hmm: