This was an aside to an article in the WSJ. i wonder why it's not getting more attention in the press?

Quote: Airbus said Thursday that ongoing studies into wave vortexes behind the double-decker airplane have found that the vortex from an A380 en route is very similar to that of a Boeing Co. (BA) 747. The study by representatives of the Joint Aviation Authorities, Eurocontrol, U.S. Federal Aviation Administration and Airbus found that there are no wake constraints for the A380 following other planes.

http://online.wsj.com/article/BT-CO-...928-710581.html?mod=moj_industries

Interesting article BoomBoom.... I am also surprised at the lack of attention to this subject... however, here on a.net, this thread will most likely grow a lot.... I suspect some here will give more details on this subject.....

I have a question, what does it say that "there is not wake constrains for the A380 FOLLOWING other planes"? I thought the major problem was other planes FOLLOWING the A380 and not vise-versa.... could someone explain this to me?

That's only a small part of the issue. A bigger problem is that, at certain airports such as San Francisco, they will not be able to do parallel approaches with the A380. They will also not be able to pass it with anything on a parallel taxiway. That will really screw me out of getting home on time. San Francisco has enough problems with the weather without having the Sky Cow throw another wrench into the works.

Also it says:

Quote: the vortex from an A380 en route is very similar to that of a Boeing 747

I thought the concern was takeoff and landing?

That's funny cause just yesterday I thought of the touch and goes in ETSI with a LH 747 and the A380 and what the results might be...

That's certainly good news! One problem less...

Quoting Atnight (Reply 1): I am also surprised at the lack of attention to this subject...

Quoting BoomBoom (Thread starter): i wonder why it's not getting more attention in the press?

Maybe the lack of attention is due to the fact that this is actually something POSITIVE about the A380.....any negative news is IMMEDIATELY reported.

Quoting Ralgha (Reply 2): A bigger problem is that, at certain airports such as San Francisco, they will not be able to do parallel approaches with the A380. They will also not be able to pass it with anything on a parallel taxiway. That will really screw me out of getting home on time. San Francisco has enough problems with the weather without having the Sky Cow throw another wrench into the works.

Righhhtt because there will be an A380 arriving every hour on the hour at SFO specifically.  

Quoting BoomBoom (Thread starter): no wake constraints for the A380 following other planes.

In addition to the "en route" thing...

Um... Wasn't the concern for other planes following the A380... not the A380 following other planes?

Quoting BoomBoom (Reply 3): Also it says: Quote: the vortex from an A380 en route is very similar to that of a Boeing 747 I thought the concern was takeoff and landing?

Thats what I thought as well.

Quoting MiCorazonAzul (Reply 5): Maybe the lack of attention is due to the fact that this is actually something POSITIVE about the A380.....any negative news is IMMEDIATELY reported.

Or maybe it's the fact that this isn't actually news?

"Airbus has completed more back-to-back tests of the A380 and other aircraft types as it seeks to accumulate data on wake vortices to back up its effort to have the separation distances recommended by the International Civil Aviation Organisation reduced.

"Airbus flight operations chief Claude Lelaie says that, in recent months, back-to-back tests of the A380 were carried out for take-off and the cruise phase against a Lufthansa Boeing 747-400, as well as other Airbus types including an A318 and A340. The cruise tests also involved aircraft flying in trail at distances of up to 15nm (28km).

"In the cruise, we looked at how the vortices descended," says Lelaie. "From our data we can see no visual difference between the 747 and A380."

"Lelaie says all the data has been presented to the ICAO working group and analysis is on-going, with a final conclusion expected by mid-November.

http://www.flightglobal.com/Articles...7/209043/+Wake+database+grows.html

see thread: A380 Wake Database Grows (by Leelaw Sep 19 2006 in Civil Aviation)#ID2995031

The strange phrasing is because it is part of an Airbus press release and they are trying to highlight the positive aspects. According to what I have heard, the A-380's operations will require 2-4 minute increased spacing (depending on the size of the following aircraft) on take-offs and landings between itself and following aircraft.

I cannot find the link at this time, but it should be published by Airbus shortly.

Here's a link for you:

http://www.skycontrol.net/business-g...-a380-wake-vortex-study-completed/

I was pretty close.

On approach, the spacing for the following aircraft is increased compared with the existing separation rules for aircraft currently in service, by two nm for another “heavy”, by three nm for a “medium” sized aircraft, and by four nm for a “light” aircraft. However, because there are no constraints for the A380 following another aircraft, the A380 can land as close as practicable to the preceding aircraft. This can compensate for the additional spacing required for the following one.

On departures, a “heavy” aircraft following the A380 will have to wait two minutes, and the “medium” sized and “light” aircraft will have to wait three minutes. But here again, the A380 can take-off as close as possible to any preceding airliner. (See details in table below)



No wake constraint for the A380 as a following aircraft

A380 followed by Heavy = +2nm extra to existing ICAO separation (6 nm absolute distance)

A380 followed by Medium = +3nm extra to existing ICAO criteria (8 nm absolute distance)

A380 followed by Light = +4nm extra to existing ICAO separation criteria (10 nm absolute distance)

[Edited 2006-09-28 19:57:48]

[Edited 2006-09-28 19:59:14]

Quoting Khobar (Reply 8): Or maybe it's the fact that this isn't actually news?

Agreed!

Enroute wake vortices are almost never a concern. I'm not sure why that was mentioned in the article, but my guess is that they are trying to quantify the 380's vortex profiles (in general) to that of the 744. Unfortunately, just because they are similar enroute doesnt mean that they are similar when it really matters near the airports.

Quoting Khobar (Reply 8): Or maybe it's the fact that this isn't actually news?

No, it isn't news. The article says nothing new other than when the data will be submitted.

Quoting DLPMMM (Reply 9): The strange phrasing

Actually, it's careful phrasing.

The first line is an Airbus claim, the second is a finding by the authorities. But the way it is written, it sounds as if the first claim is from the authorities. It is NOT. It is from Airbus PR department.

The A380 vortex is "very similar" and that has been Airbus's claim for a while now. Before it flew, the claim was "less than" or "the same as" but has changed to "very similar." This is because testing has determined it is not the same.

In flight spacing was never really in question. The A380 was never thought to need greater follow spacing, nor was it thought that other planes would have to follow behind it differently in cruise.

It was the approach and takeoff spacing that was in question, and this little blurb says nothing about that. WSJ is a subscription site, so a link to a free article with any new information would be appreciated. This article doesn't look to have any new information.

Ikramerica,

Please read the article that I linked to.

The results of the study do say that additional spacing will be required for following aircraft.

The article was just published today.

Cheers

Prvious to the ICAO interim recommendation from Nov. 05. Airbus stated the the separation rules for the A380 would be no different than for the 747-400. Now with this they are confirming in fact that the separation distance will be greater for aircraft following compared to the 744 in a similar circumstance. Actually this all in all in not good news for the A380 as it will place trailing aircraft farther behind the A380 thus increasing congestion at the airports.

Quoting Ikramerica (Reply 13): This thread title is not factual but is very, very, very misleading. It should be changed.

Absolutely....  , I thought new wake data came out which showed it to be no different than a 747....but there is nothing new here..and this hasn't changed....

"Approach / Landing: No wake constraint for the A380 as a following aircraft. A380 followed by Heavy = +2nm extra to existing ICAO separation (6 nm absolute distance). A380 followed by Medium = +3nm extra to existing ICAO criteria (8 nm absolute distance). A380 followed by Light = +4nm extra to existing ICAO separation criteria (10 nm absolute distance)"

this is where the debate on A.net was mostly about...

Quoting NYC777 (Reply 15): Actually this all in all in not good news for the A380 as it will place trailing aircraft farther behind the A380 thus increasing congestion at the airports.

But the A380 can follow an aircraft with no restrictions, allowing them to close up that 'extra' seperation required.

Its all much of a muchness.

Quoting RichardPrice (Reply 17): But the A380 can follow an aircraft with no restrictions, allowing them to close up that 'extra' seperation required.

Won't make a difference...it will still have the same "bottleneck effect"...it was already assumed that the A380 won't have any wake constraints...

Quoting DLPMMM (Reply 14): The results of the study do say that additional spacing will be required for following aircraft.

Our posts were close together, and yours wasn't up when i started responding.

So your article agrees that the title of the thread is 180 degrees wrong.

What is interesting is that the A380 is clearly inferior to the 744 for spacing, as the 744 can also follow any other aircraft on takeoff and landing closely (except for the A380). So the A380 introduces a problem on both ends, and the proposal to "compensate" also applies to the 747. Any scheme used to compensate for an A380 could also be used to further improve ops at an airport for the 747. The 744, under this scheme will ALWAYS have and advantage, and that advantage, when multiplied by the seating in service of the 744 vs. the 388, makes the A380 a wash in terms of operations at slot constrained airports.

Thus, for airlines like BA, JL, NH, etc., there is no benefit to be had by using the A380 at this time in terms of slots. For airlines with only 1 slot into a slot controlled airport, there is a benefit as it allows them to carry more pax into that airport with that slot. But if there is a negative impact on ops, that slot may have to be valued differently, and the benefit may be negated there as well.

Sticky wicket...

quote from article:
"These values are subject to review and possible reduction based on further study or changes in aircraft categories and operational experience. A significant aspect of this new guidance is that it has revealed the need for a future review of the existing aircraft categories, also taking into account operational experience."

This is what I've been saying all along. The current categories are so broad and pointless, they need to be reviewed.

EADS's press release:

http://www.eads.com/web/main/en/1024...F00000040950509/2/52/41478522.html
Vertical Spacing:

• Vertical spacing in all cases to be the same as for other aircraft.
  
• Evidence and data from encounter flight tests at cruise altitude, supported by airborne LIDAR measurements, have demonstrated that the A380 wake characteristics are equivalent to those of the B744 (chosen as the benchmark aircraft) for this phase of flight. Therefore, the current ICAO vertical separations are confirmed to be appropriate for A380 operations.
  

Horizontal spacing en-route:

• En-route horizontal spacing to be the same as for other aircraft
  

Holding:

• Vertical spacing to be the same as for other aircraft
  

Approach / Landing:

• No wake constraint for the A380 as a following aircraft
  
• A380 followed by Heavy = +2nm extra to existing ICAO separation (6 nm absolute distance)
  
• A380 followed by Medium = +3nm extra to existing ICAO criteria (8 nm absolute distance)
  
• A380 followed by Light = +4nm extra to existing ICAO separation criteria (10 nm absolute distance)
  

Departure following A380:

• No wake constraint for the A380 as a following aircraft.
  
• Same radar spacing as for Approach / Landing
  
• Or, for time based operations: Heavy = 2 minutes; Medium, Light = 3 minutes.
  

The title isn't misleading, it's just consise to the point that it opens up multiple interpretations, which means people are confused.

The title is "No Wake Constraints for A380". The article says that the A380 has no restrictions on the kinds of wakes IT can fly into. Therefore, it is accurate. Since most people are still thinking about the kinds of seperation constraints the A380 puts on other aircraft because of the wake it generates, they're interpreting it that way. That doesn't make the title misleading however, it just means you need to read the content carefully.

I find this interesting by the way. Are there normally arrival and departure constraints for two of the current generation heavys? i.e. two 744's following each other in for landing, or departing one after another? Also, does this apply to two A380's in series on both arrival and departure? It's not clear to me...

Guys, let's not mix up everything...

They get the same enroute seperation, that's the only 'new' fact!

The approach and landing separation minimas are temporary restrictions untill they found out if the A380 creates stronger vortex than the 747 or not, and this will be done by november as stated somewhere above!

So no good news/bad news/bottleneck or whatever here...

Quoting EDDB (Reply 22): They get the same enroute seperation, that's the only 'new' fact! The approach and landing separation minimas are temporary restrictions untill they found out if the A380 creates stronger vortex than the 747 or not, and this will be done by november as stated somewhere above! So no good news/bad news/bottleneck or whatever here...

No EDDB, the approach, landing, and take-off separation minimas outlined are the new recommendations by the cognizant organizations based on the new vortex studies that have now been completed.

Please read the article.

Quoting Ikramerica (Reply 19): Thus, for airlines like BA, JL, NH, etc., there is no benefit to be had by using the A380 at this time in terms of slots.

Not entirely true...if you sequence enough consecutive A380 flights together, you only lose out on time on the back end of that series of flights. That would require quite a number of them flying in and out however, with favorable schedules. Highly unlikely, but not impossible with a big enough fleet out of your own hub. The problem then becomes the customs and checkin nightmares. Deplaning 10 of those monsters in such short order will not fun for anyone on the ground.  

Quoting Ralgha (Reply 2): That will really screw me out of getting home on time. San Francisco has enough problems with the weather without having the Sky Cow throw another wrench into the works.

it's just me me me with you! Love the name sky cow moooowooosh

Quoting NYC777 (Reply 15): Actually this all in all in not good news for the A380 as it will place trailing aircraft farther behind the A380 thus increasing congestion at the airports.

Quoting Ikramerica (Reply 19): What is interesting is that the A380 is clearly inferior to the 744 for spacing...... The 744, under this scheme will ALWAYS have and advantage, and that advantage, when multiplied by the seating in service of the 744 vs. the 388, makes the A380 a wash in terms of operations at slot constrained airports.

Quoting Ikramerica (Reply 19): The current categories are so broad and pointless, they need to be reviewed.

You start off slating the 380 then by the end of it you come round saying that rules are aginst it. I think you were in a bad mood.

ATC and Airports around the world are filled with clever creative people, they'll work out new procedures that ensure profitability and maximum useage for all.

Oops, missed the last posts before my own (or do I hack my thoughts into the computer this slow?   )

Quoting Ralgha (Reply 2): That's only a small part of the issue. A bigger problem is that, at certain airports such as San Francisco, they will not be able to do parallel approaches with the A380. They will also not be able to pass it with anything on a parallel taxiway. That will really screw me out of getting home on time. San Francisco has enough problems with the weather without having the Sky Cow throw another wrench into the works.

About time the USA spent some time upgrading its airports. If a third world country like Thailand can spent billions building a new international airport, so can the USA.

Quoting DLPMMM (Reply 10): On approach, the spacing for the following aircraft is increased compared with the existing separation rules for aircraft currently in service, by two nm for another "heavy", by three nm for a "medium" sized aircraft, and by four nm for a "light" aircraft. However, because there are no constraints for the A380 following another aircraft, the A380 can land as close as practicable to the preceding aircraft. This can compensate for the additional spacing required for the following one. On departures, a "heavy" aircraft following the A380 will have to wait two minutes, and the "medium" sized and "light" aircraft will have to wait three minutes. But here again, the A380 can take-off as close as possible to any preceding airliner. (See details in table below)

You can slot a landing between two departures, or a takeoff between two landings without any constraint.

Quoting Charliejag1 (Reply 11): Enroute wake vortices are almost never a concern.

I find them to be a very annoying surprise. Strategic lateral offsets of 2nm have been around for some time as they are a problem.

Quoting Ikramerica (Reply 12): The A380 vortex is "very similar" and that has been Airbus's claim for a while now. Before it flew, the claim was "less than" or "the same as" but has changed to "very similar." This is because testing has determined it is not the same.

I dont recall seeing it being claimed as less. Please do not assume what has been announced is final, it is less than what the 747 had when it entered service.

Please note that standard ICAO heavy separation has been applied for some time now at TLS, except for when testing required otherwise. For circuits it ICAO standard heavy separation.

Quoting Jacobin777 (Reply 18): Won't make a difference...it will still have the same "bottleneck effect"...it was already assumed that the A380 won't have any wake constraints...

I dont recall anyone ever assumed it would have no wake constraints.

Quoting Ikramerica (Reply 19): What is interesting is that the A380 is clearly inferior to the 744 for spacing, as the 744 can also follow any other aircraft on takeoff and landing closely (except for the A380). So the A380 introduces a problem on both ends, and the proposal to "compensate" also applies to the 747. Any scheme used to compensate for an A380 could also be used to further improve ops at an airport for the 747. The 744, under this scheme will ALWAYS have and advantage, and that advantage, when multiplied by the seating in service of the 744 vs. the 388, makes the A380 a wash in terms of operations at slot constrained airports.

When people come to replace their 744s, they have two options, the 380 or 748, I would suggest they will be the same wake separation.

The 744 has disadvantages, it stopped being sold, uses more runway, and airlines are putting less seats in aircraft.

Quoting Ikramerica (Reply 19): Thus, for airlines like BA, JL, NH, etc., there is no benefit to be had by using the A380 at this time in terms of slots. For airlines with only 1 slot into a slot controlled airport, there is a benefit as it allows them to carry more pax into that airport with that slot. But if there is a negative impact on ops, that slot may have to be valued differently, and the benefit may be negated there as well.

The separations from what I can see look exactly like what the current ones are for LHR/LGW, the slot constrained airport that will see the majority of initial A380 operations.

ICAO/UK/FAA do not have the same separation standards, UK standards have increased distances above ICAO.

From my understanding radar separation will still be 2.5-3nm (66-79 seconds).

Quoting Jdevora (Reply 20): Approach / Landing: No wake constraint for the A380 as a following aircraft A380 followed by Heavy = +2nm extra to existing ICAO separation (6 nm absolute distance) A380 followed by Medium = +3nm extra to existing ICAO criteria (8 nm absolute distance) A380 followed by Light = +4nm extra to existing ICAO separation criteria (10 nm absolute distance)

I think these are the UK ones for LHR/LGW.

Moderators - have to agree, please change this title as it is indeed very mis-leading.

This news is indeed quite a set-back for the A380 operationally. One of the major premises for this aircraft was it would serve to relieve slot congestion and these new takeoff/landing restrictions nullify that benefit.

Have to say I love the EADS press release format:
1) inconsequential positive statement
2) inconsequential positive statement
3) inconsequential positive statement
4) CATASTROPHIC negative impact**

**please pay ignore that last bit....move along please...

Quoting Zeke (Reply 27): You can slot a landing between two departures, or a takeoff between two landings without any constraint.

Quoting Zeke (Reply 27): I find them to be a very annoying surprise. Strategic lateral offsets of 2nm have been around for some time as they are a problem.

You know what you're talking about!
  

Quoting Lemurs (Reply 24): That would require quite a number of them flying in and out however, with favorable schedules.

Exactly. That's a LONG way off. Which is why I say "at this time."

In theory, if all you were flying was the A380, you'd get a huge amount of capacity increase at LHR for example.

Not going to happen.

Quoting EbbUK (Reply 25): You start off slating the 380 then by the end of it you come round saying that rules are aginst it. I think you were in a bad mood.

I wasn't, but now I am! I state the g-damn FACTS and that's "slating" the a380? The facts are not disputable at this stage. It's how things ARE and WILL BE for the foreseeable future.

You spout misinformation above, so get off your high horse and pay attention. These are no longer temporary restrictions.

The A380 is not meeting promises of equal spacing to the 747, a huge factor in the case for A380 in the first place!!!!!!!!!

Here's some more of these, for impact. !!!!!!!!!

It will NOT increase capacity at a slot controlled airport in any meaningful way. That is now established. Anything an airport does to accommodate the aircraft like LHR is proposing could just as easily have been done for EXISTING 744s, proving that LHR and other airports were not doing as much as they could to increase capacity in the first place!

Further, if you had bothered to read any of the threads on this in the past on this (or my posts within them), I've repeatedly pointed out that the whole "heavy, medium, light" thing is antiquated and needs to go. The A388 is in a class by itself right now. But even attempting to put it in the same class as the 763, for example, shows how silly the whole thing is.

If anything good comes of this, we will have a reclassing of many aircraft, and spacing can tighten up in a variety of situations. This would increase capacity at any airport that is slot (not gate) constrained, whether an A380 ever lands there or not, as long as it has at least two runways and varied types of aircraft that arrive throughout the day.

Quoting Ikramerica (Reply 30): In theory, if all you were flying was the A380, you'd get a huge amount of capacity increase at LHR for example. Not going to happen.

Why not? Usually one rwy at LHR is used for take offs, one for landing... Only thing ATC must do is let the A380 land on the take off rwy! And since I rate the London ATC guys among the best in the world, it should be doable...

So, a WhaleJet following an Eclipse doesn't need extra spacing. What a relief! I know we had all been so worried about that.  

Quoting TrevD (Reply 28): Moderators - have to agree, please change this title as it is indeed very mis-leading. This news is indeed quite a set-back for the A380 operationally. One of the major premises for this aircraft was it would serve to relieve slot congestion and these new takeoff/landing restrictions nullify that benefit. Have to say I love the EADS press release format: 1) inconsequential positive statement 2) inconsequential positive statement 3) inconsequential positive statement 4) CATASTROPHIC negative impact** **please pay ignore that last bit....move along please...

   The thread title definitely needs to be changed.

Quoting Ikramerica (Reply 30): Further, if you had bothered to read any of the threads on this in the past on this (or my posts within them), I've repeatedly pointed out that the whole "heavy, medium, light" thing is antiquated and needs to go. The A388 is in a class by itself right now. But even attempting to put it in the same class as the 763, for example, shows how silly the whole thing is. If anything good comes of this, we will have a reclassing of many aircraft, and spacing can tighten up in a variety of situations. This would increase capacity at any airport that is slot (not gate) constrained, whether an A380 ever lands there or not, as long as it has at least two runways and varied types of aircraft that arrive throughout the day.

Another question on this: Who is responsible for setting and communicating spacing between a/c in the patern? I assume ATC. If so, that may be one reason this hasn't been revisited. Adding too many categories could take a quick from-memory decision and make it a calculation or paper-reference item, which increases the odds for mistakes and the load on already-busy ATC.

When you take safety concerns as your primary factor and apply KISS principles to create an answer, you end up with a conservative, simplistic solution...but you know it'll meet your goals.

Just a possible reason it hasn't come up already.

Quoting Zeke (Reply 27): I dont recall anyone ever assumed it would have no wake constraints.

It was in response to this comment..

Quoting RichardPrice (Reply 17): But the A380 can follow an aircraft with no restrictions, allowing them to close up that 'extra' seperation required

Quoting Zvezda (Reply 32): So, a WhaleJet following an Eclipse doesn't need extra spacing. What a relief! I know we had all been so worried about that. Yeah sure

  

Quoting Ikramerica (Reply 30):

I read with great sadness that following my post you lost your marbles.

You are right, I didn't spend too much energy reading your posts in this thread. Because as you have said, the guidelines need re-working. Airbus agree. You want the 380 in a category of its own, Airbus, however, are optimistic that with time in service, those timings will be shaved.

"These values are subject to review and possible reduction based on further study or changes in aircraft categories and operational experience. A significant aspect of this new guidance is that it has revealed the need for a future review of the existing aircraft categories, also taking into account operational experience."
http://www.eads.com/web/lang/en/1024...F00000040950509/2/52/41478522.html

Who'll be right? who'll be wrong? who'll be happy? I hope you will be, soon.

Quoting Jacobin777 (Reply 18): Won't make a difference...it will still have the same "bottleneck effect"...it was already assumed that the A380 won't have any wake constraints...

As I understood it, although the A380 requires greater separation from the aircraft behind (than the 747, say), it can actually operate a reduced separation from the aircraft in front (than a 747, say), allowing the difference to be minimised.
Therefore the key is not that there are "no restrictions" per se, but that "no restrictions" allows the A380 to close up on the aircraft in front.

Quoting RichardPrice (Reply 17): But the A380 can follow an aircraft with no restrictions, allowing them to close up that 'extra' seperation required.

  .

Regards

Quoting Astuteman (Reply 36): As I understood it, although the A380 requires greater separation from the aircraft behind (than the 747, say), it can actually operate a reduced separation from the aircraft in front (than a 747, say), allowing the difference to be minimised. Therefore the key is not that there are "no restrictions" per se, but that "no restrictions" allows the A380 to close up on the aircraft in front.

Astuteman, I do understand what you are saying..however..I think the quote below was the point I was attempting to make.....

Quoting Ikramerica (Reply 19): What is interesting is that the A380 is clearly inferior to the 744 for spacing, as the 744 can also follow any other aircraft on takeoff and landing closely (except for the A380). So the A380 introduces a problem on both ends, and the proposal to "compensate" also applies to the 747. Any scheme used to compensate for an A380 could also be used to further improve ops at an airport for the 747. The 744, under this scheme will ALWAYS have and advantage, and that advantage, when multiplied by the seating in service of the 744 vs. the 388, makes the A380 a wash in terms of operations at slot constrained airports.

Quick thoughts...

Quoting Ikramerica (Reply 30): It will NOT increase capacity at a slot controlled airport in any meaningful way. That is now established.

No it has not. 1) because it can fly closer to preceding aircrafts than other aircrafts can 2) because obviously if you pipeline several A380 landing in succession you obviously factor out the increase - and may even decrease overall since they can fly closer. 3 successive A380 may be enough to decrease overall landing sequence 3) The current temporary separation guidelines are just that. Temporary and guidelines. 4) The all separation rules may need a full revamp. You can not claim that say the B748 is a superjumbo competing against it and at the same time put it into the same separation bracket as say a B767.

Quoting Ikramerica (Reply 30): The A388 is in a class by itself right now.

The A388 is using heavy separation right now in daily operations in Toulouse.

My belief is that this may be a real concern for Airbus if the ICAO maintains its separation as is. Now I could not stress enough the fact that if EK/SQ pressure Asian airports to use the same separation as what say Airbus themselves has been using for more than one year, then whatever US-biased separations might be suggested by the ICAO nobody cares. Wildly speaking the US don't like the A380 - so what, its market is not there. It's not like it killed Concorde...

And I am glad that nobody used the size of the A388 as an argument as to why it should have a higher wake. That (nonsensical) argument works in the media but gladly enough not with tech-savvy A.netters...

Quoting Ikramerica (Reply 30): The A380 is not meeting promises of equal spacing to the 747, a huge factor in the case for A380 in the first place!!!!!!!!!

I think you may be jumping to conclusions.

Heavy behind Heavy: 4 nm
Heavy behind A380: 6 nm
A380 behind Heavy: no restriction (i.e. 2 nm is okay)

If true, this is a major vindication of the A380 business case, as the whole wake separation issue is dismissed-- as in, no reduction in throughput.

Quoting BoomBoom (Reply 3): I thought the concern was takeoff and landing?

Quoting Charliejag1 (Reply 11): Enroute wake vortices are almost never a concern.

Generally takeoff and landing wake is the larger concern because wake is greatest at low speed and high angles of attack, ie takeoff and landing. However, wake is still a serious issue for enroute, especially for large heavies. I ran through a B742 wake at between 15 and 20 miles in trail a few years ago. We were at FL310 and he was climbing out and was quite heavy with a load going to Asia. At that weight and altitude his angle of attack was quite high, the airspeed was low for his configuration making his wake intense. It rolled us just shy of 45 degrees before I could pull above his wake and roll out of it. It also took over 200 feet of climb before we got out of the bumps. This will be a concern with the A388 climbing out and leaving a large core of wake behind it.

Quoting Glacote (Reply 38): Now I could not stress enough the fact that if EK/SQ pressure Asian airports to use the same separation as what say Airbus themselves has been using for more than one year, then whatever US-biased separations might be suggested by the ICAO nobody cares.

Very good point. What testing has Airbus done to validate that their current wake turbulance procedure for TLS is accurate? Further more I've been to TLS. It is a moderately busy airport but I would not say that it is a high density airport. How often have they had the need to sequence other aircraft at minimum spacing behind an A388 on the approach?

The A388 is so much larger in terms of wake signature than the B744 that I think good, unbiased testing should be done. Airbus has too much at stake to do the testing themselves. The FAA is too ignorant with too many politicians pulling their puppet strings to run the testing. Perhaps this should be done by a neutral source with a great reputation for being unbiased like the Flight Safety Foundation or the Royal Aeronautical Society. Either way it needs to be done for the safety of not just the flying public but for the people who the aircraft will be flying over as well.

727forever

Another thing to consider about the A380.

Since it will requires longer runway than other heavies, it will be on the runway a good distance more than other heavies (extra ~20 seconds). But hey, more time is more time. 20 seconds or so, that's about a mile...isn't it?

Quoting Zeke (Reply 27): About time the USA spent some time upgrading its airports. If a third world country like Thailand can spent billions building a new international airport, so can the USA.

Nice post. Upgrades cost money as much as time. Many markets are fragmented. If SEA spends the money, and no A380 visits, what was the point? If SFO adds taxiway space, but only sees two or three A380's a day, what was the point?

Conversely, if Thailand believes they need to spend the money to accommodate the A380, good for them. If Canada wants to spend the money to upgrade, what, three airports, good for them.

I can think of a lot of other things that we (Americans) could spend money on in our transportation system than upgrading numerous airports in hopes of seeing a handful of A380's a day - if that - if ever.

-Dave

Quoting WingedMigrator (Reply 39): If true, this is a major vindication of the A380 business case, as the whole wake separation issue is dismissed-- as in, no reduction in throughput.

Absolutely wrong... Am amazed how many people are not getting the picture here. The issue isn't how close behind another aircraft the A380 can follow in trail, the issue is how close another aircraft can trail the A380.

That A320 that following the A380 in to land at LHR with a planeload of passengers for that next out-bound A380 flight now has to follow 4nm or 2 minutes behind.

Quoting Ralgha (Reply 2): That's only a small part of the issue. A bigger problem is that, at certain airports such as San Francisco, they will not be able to do parallel approaches with the A380.

They already have that restriction in place for all 747 landings on Runways 28L/28R, so the effect is much less than you think.

Quoting RayChuang (Reply 44): They already have that restriction in place for all 747 landings on Runways 28L/28R, so the effect is much less than you think.

  ..........I've seen parallel landings with a 747 and 737.....now if you are talking about 2 parallel 747's landings...that would be a sight to see...  

Quoting Glacote (Reply 38): 1) because it can fly closer to preceding aircrafts than other aircrafts can

Than a Jumbo?

Quoting Glacote (Reply 38): 2) because obviously if you pipeline several A380 landing in succession you obviously factor out the increase

Just have it circle for a few hours until the next one shows up.

Quoting 727forever (Reply 40): Very good point. What testing has Airbus done to validate that their current wake turbulance procedure for TLS is accurate? Further more I've been to TLS. It is a moderately busy airport but I would not say that it is a high density airport. How often have they had the need to sequence other aircraft at minimum spacing behind an A388 on the approach? The A388 is so much larger in terms of wake signature than the B744 that I think good, unbiased testing should be done. Airbus has too much at stake to do the testing themselves. The FAA is too ignorant with too many politicians pulling their puppet strings to run the testing. Perhaps this should be done by a neutral source with a great reputation for being unbiased like the Flight Safety Foundation or the Royal Aeronautical Society. Either way it needs to be done for the safety of not just the flying public but for the people who the aircraft will be flying over as well.

DERA installed LIDAR at TLS, the have been measuring the wake characteristics of just about every aircraft landing there for a long time. A similar installation is installed at FRA, and NASA/FAA as far as I know have installed similar equipment to three airports in the USA.

Testing has been done for many years now, it has been a collaboration between government, university, and corporate researchers. Information has been shared across the board. A lot of the early work came from NASA over twenty years ago.

The testing has shown that the 380 does not have a "much larger in terms of wake signature than the B744". It has a lower vortex core velocity than the 744 which would lead to smaller induced rolling moments if encountered by a trailing aircraft. It does have a slight larger vortex diameter, with a smaller core velocity, and it has been found that the mixing of the cores from either side occur quicker on the 380 than 744, when they mix the two cores destroy each other.

Quoting N908AW (Reply 41): Since it will requires longer runway than other heavies, it will be on the runway a good distance more than other heavies (extra ~20 seconds). But hey, more time is more time. 20 seconds or so, that's about a mile...isn't it?

This is incorrect, the 380 will use less runway and should have lower runways occupancy times than the 747 and 777 as it has a smaller landing distance and lower approach speeds (about 30kt slower than a 744 or 773ER).

The 380 also has brake to vacate which optimises the landing roll to come to taxi speed for a particular runway exit.

Quoting PlanesNTrains (Reply 42): Nice post. Upgrades cost money as much as time. Many markets are fragmented. If SEA spends the money, and no A380 visits, what was the point? If SFO adds taxiway space, but only sees two or three A380's a day, what was the point?

As far as I know SEA accommodate 747s on concession at the moment, a lot of airports in the USA do not meet current requirements for 747s.

BKK got replaced as it was getting old, and the takeoff path basically took you over the royal palace. The sole reason was not for A380 upgrades, they built a new gateway to their country.

First impressions count.

Quoting TrevD (Reply 43): That A320 that following the A380 in to land at LHR with a planeload of passengers for that next out-bound A380 flight now has to follow 4nm or 2 minutes behind.

This is incorrect at LHR/LGW as far as I am aware. Radar separation will still be 2.5-3nm (66-79 seconds).

At LHR/LGW for takeoff anything smaller than a heavy following a heavy from the same departure point = 2 minutes. For landing and medium following medium = 3 miles, note - if the first a/c is an upper medium (104t to 162t MTOW ie B757, DC8, B707, IL62, VC10), the distance will be 4 miles, medium following heavy = 5 miles.

Also for for intermediate approach in the UK, a medium, small or light aircraft are to cross behind or follow the same track as a heavy aircraft, the minimum distance will be 5 miles. There is no requirement for any separation between medium and light for example, although ATC are encouraged to use common sense.

From what I have seen so far, at LHR/LGW no change at all, no special treatment.

Quoting Zeke (Reply 47): As far as I know SEA accommodate 747s on concession at the moment, a lot of airports in the USA do not meet current requirements for 747s.

If you are saying that SEA doesn't meet current requirements for 747's, then I guess it is working because I haven't heard a major uproar about their arrivals/departures.

Applying the same standard to the A380, I guess if an airport can avoid perhaps ten's of millions of dollars in expenses and still accommodate a handful of daily A380 arrivals, I don't see the problem.

Quoting Zeke (Reply 47): BKK got replaced as it was getting old, and the takeoff path basically took you over the royal palace. The sole reason was not for A380 upgrades, they built a new gateway to their country.

I guess I'm trying to draw the line between this thread on A380's and Bangkok having multiple reasons for building a new airport? Is your point that the US is somehow rolling in money and we should just be building airports so we have a great "first impression"?

If an airport feels it needs to spend the money to handle the A380, knowing it will make up the cost in increased revenues/fees, fine. But I don't think there are many airports in the US that should be running out and writing the check just yet. It will literally be years before a significant number of A380's will exist to land at any one US airport on a given day.

-Dave

Quoting N908AW (Reply 41): Since it will requires longer runway than other heavies, it will be on the runway a good distance more than other heavies (extra ~20 seconds). But hey, more time is more time. 20 seconds or so, that's about a mile...isn't it?

What are you talking about? The WhaleJet doesn't need more runway than other heavies.

Quoting PlanesNTrains (Reply 42): If SFO adds taxiway space, but only sees two or three A380's a day, what was the point?

SFO is already ready for the WhaleJet.

Quoting Zeke (Reply 47): a lot of airports in the USA do not meet current requirements for 747s.

There are about 5000 airports in the States. There are 210 airports in the world with everything in place for regular passenger JumboJet ops. Clearly, over 4000 airports in the States do not meet current requirements for JumboJets. So what?

Quoting TrevD (Reply 43): Absolutely wrong... Am amazed how many people are not getting the picture here. The issue isn't how close behind another aircraft the A380 can follow in trail, the issue is how close another aircraft can trail the A380.

You've got a point when something small is following the A380. But when an A380 is slotted into a steady stream of heavies, there is no impact to the approach throughput. That is because the A380 is not restricted to 4 nm behind other Heavies.... so how closely the A380 can trail another aircraft is indeed very much part of the point.

Quoting Zvezda (Reply 46): Quoting Glacote (Reply 38): 1) because it can fly closer to preceding aircrafts than other aircrafts can Than a Jumbo?

When following a Heavy, that is indeed what the EADS press release seems to say. Whether the Jumbo would be allowed to follow another Heavy more closely than 4 nm is a fair question, but it is not the matter at hand.