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Jay Honeck
November 22nd 05, 10:24 PM
Yee-hah! Don't get too close to this whale...

Change in Rules
Needed for Wake
Of Big New Jet

By ANDY PASZTOR and DANIEL MICHAELS
Staff Reporters of THE WALL STREET JOURNAL
November 22, 2005; Page B1

Airliners may have to fly twice the normal distance behind the new
Airbus A380 superjumbo jet to avoid potential hazards from its
unusually powerful wake, according to preliminary safety guidelines.

The standards released to the industry by the International Civil
Aviation Organization earlier this month are tentative and almost
certainly more cautious than the formal rules expected next year. But
if the final air-traffic procedures end up close to ICAO's initial
proposal, they could undermine one of Airbus' top selling points for
the largest passenger plane ever built: greater efficiency at congested
hub airports.

Interim air-traffic control guidance from ICAO says the mammoth plane,
scheduled to go into service next year, produces "significantly
stronger" air turbulence than the largest jetliners now in use. Because
flight tests and data analyses "have raised concerns" about potential
safety issues, according to the guidance, it calls for minimum
separations of 10 nautical miles for all aircraft following a landing
A380, versus the typical five-mile mandatory buffer behind today's
largest aircraft.

For aircraft flying the same route directly behind an A380 at cruising
altitude, the recommended minimum spacing is tripled to 15 nautical
miles.

The interim rules are "very conservative" and will remain effective
"until conclusive guidance is issued mid-next year," said Paul Wilson,
a senior European air-traffic control official who is helping lead the
study. Initial plans called for the effort to be completed around
January, but now "there's a feeling more work needs to be done," Mr.
Wilson said yesterday in an interview. "What we want to do is get it
right" and rely on hard data, he added, because "we are leading the way
for all future aircraft" operating criteria.

The ICAO is a global aviation regulator whose standards and rules are
almost always accepted by individual governments.

Airbus, which touts the 555-seat A380 as "the economical solution for
heavily traveled routes," has sold it as a way to carry more traffic
without adding aircraft. The twin-deck jetliner can carry at least 35%
more passengers than Boeing Co.'s largest model, the 747-400. In some
configurations, the plane can handle more than 850 passengers.

The preliminary rules are already grabbing notice from Airbus
customers. A spokesman for Germany's Lufthansa, which has ordered 15
A380s, said "it is crucial for us that the separation is the same as
for a 747" because "we operate at congested airports."

The two-page ICAO advisory not only deals with the safety aspects of
air turbulence at low altitudes near airports but even raises questions
about potential hazards for nearby aircraft in midflight. The guidance
says the so-called wake vortices produced by the A380 -- twin cones of
turbulent air fanning out from its wingtips -- "will descend further
and be significantly stronger" than those from other large jets,
potentially even affecting jets traveling in the opposite direction
some 2,000 feet below. "Because it has not yet been possible to
establish the level of hazard" from such turbulence, the guidance
recommends "offset tracks or additional vertical spacing" for added
protection.

When an airborne aircraft runs into such turbulence, the impact can
jostle the trailing plane. In extreme circumstances, the result can
even be loss of control, though there haven't been any recent crashes
of jetliners attributed primarily to such encounters. Many years ago
the U.S. Federal Aviation Administration had to lengthen spacing
requirements for planes flying behind Boeing 757 jetliners, following a
fatal crash of a business jet that ran into a 757's wake.

Airbus has said the four-engine plane, with a maximum takeoff weight in
excess of a million pounds, is designed to fit seamlessly into
air-traffic systems world-wide without requiring greater spacing than
existing models or needing any other special handling by controllers.
An Airbus A380 marketing brochure in 2003, for example, said: "there is
no need to introduce any changes in separation standards" for the A380
because the aircraft's wake "is similar to that of the 747-400."

A spokesman for Airbus, which is owned 80% by European Aeronautic
Defence & Space Co. and 20% by Britain's BAE Systems PLC, declined to
comment, citing the ongoing studies. Despite the success Airbus has had
using computers to precisely predict handling and other characteristics
of the new plane, "we are still in the Stone Age for modeling" wake
turbulence, said Robert Lafontan, the A380's chief engineer, in an
interview several weeks ago.

The interim guidelines also recommend an additional wait of one minute
-- on top of today's typical two-minute spacing -- for smaller
jetliners taking off directly behind the giant A380. Once the A380
reaches cruising altitude, the guidance suggests that on "rare
occasions" its wake may be strong enough to shake planes flying nearly
half a mile below it and end up creating a "comfort issue" for
passengers in those jets.

With less than 160 orders and commitments for the A380, Airbus needs
about 90 more to break even. But the market is becoming more
competitive with Boeing's announcement that it is offering a larger 747
version.

The FAA, while particularly sensitive about any perception that it is
discriminating against the European planemaker, has been quietly
pushing for additional testing and more restrictive rules, industry
officials say. At the beginning of the year, an internal FAA report
projected that the A380's wake may result in fewer arrivals at some
airports; that the plane may require extra time or distance to execute
a missed approach to a runway; and it "may have an adverse impact" on
general airport operations. Air-traffic control officials, the report
concluded, are "uncomfortable" with the A380 and need answers quickly.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Peter R.
November 22nd 05, 10:29 PM
Jay Honeck > wrote:

> Airliners may have to fly twice the normal distance behind the new
> Airbus A380 superjumbo jet to avoid potential hazards from its
> unusually powerful wake, according to preliminary safety guidelines.
<snip>

Airbus should include color smoke generators off each wingtip to colorize
the vortices and give VFR aircraft something visually to avoid. :)

--
Peter

Matt Whiting
November 22nd 05, 11:42 PM
Jay Honeck wrote:

> Yee-hah! Don't get too close to this whale...
>
> Change in Rules
> Needed for Wake
> Of Big New Jet
>
> By ANDY PASZTOR and DANIEL MICHAELS
> Staff Reporters of THE WALL STREET JOURNAL
> November 22, 2005; Page B1
>
> Airliners may have to fly twice the normal distance behind the new
> Airbus A380 superjumbo jet to avoid potential hazards from its
> unusually powerful wake, according to preliminary safety guidelines.
>
> The standards released to the industry by the International Civil
> Aviation Organization earlier this month are tentative and almost
> certainly more cautious than the formal rules expected next year. But
> if the final air-traffic procedures end up close to ICAO's initial
> proposal, they could undermine one of Airbus' top selling points for
> the largest passenger plane ever built: greater efficiency at congested
> hub airports.
>
> Interim air-traffic control guidance from ICAO says the mammoth plane,
> scheduled to go into service next year, produces "significantly
> stronger" air turbulence than the largest jetliners now in use. Because
> flight tests and data analyses "have raised concerns" about potential
> safety issues, according to the guidance, it calls for minimum
> separations of 10 nautical miles for all aircraft following a landing
> A380, versus the typical five-mile mandatory buffer behind today's
> largest aircraft.

And this is a surprise? Did they think an airplane that size would have
the wake turbulence of a 737?

Matt

Jonathan
November 23rd 05, 04:19 AM
Matt Whiting wrote:

> And this is a surprise? Did they think an airplane that size would have
> the wake turbulence of a 737?

Not a 737, but Airbus was claiming it would be comparable to a 747, which is
a "heavy" aircraft. If you read the article, you might have noted that

"An Airbus A380 marketing brochure in 2003, for example, said: "there is
no need to introduce any changes in separation standards" for the A380
because the aircraft's wake "is similar to that of the 747-400.""

Jonathan
November 23rd 05, 04:20 AM
"Peter R." wrote:

> Jay Honeck > wrote:
>
> > Airliners may have to fly twice the normal distance behind the new
> > Airbus A380 superjumbo jet to avoid potential hazards from its
> > unusually powerful wake, according to preliminary safety guidelines.
> <snip>
>
> Airbus should include color smoke generators off each wingtip to colorize
> the vortices and give VFR aircraft something visually to avoid. :)

And other IFR aircraft, including jets, for that matter.

Matt Barrow
November 23rd 05, 06:30 AM
"Peter R." > wrote in message
...
> Jay Honeck > wrote:
>
>> Airliners may have to fly twice the normal distance behind the new
>> Airbus A380 superjumbo jet to avoid potential hazards from its
>> unusually powerful wake, according to preliminary safety guidelines.
> <snip>
>
> Airbus should include color smoke generators off each wingtip to colorize
> the vortices and give VFR aircraft something visually to avoid. :)
>

Different color smoke from each wingtip would be very pretty.

Matt Whiting
November 23rd 05, 12:14 PM
Jonathan wrote:
> Matt Whiting wrote:
>
>
>>And this is a surprise? Did they think an airplane that size would have
>>the wake turbulence of a 737?
>
>
> Not a 737, but Airbus was claiming it would be comparable to a 747, which is
> a "heavy" aircraft. If you read the article, you might have noted that
>
> "An Airbus A380 marketing brochure in 2003, for example, said: "there is
> no need to introduce any changes in separation standards" for the A380
> because the aircraft's wake "is similar to that of the 747-400.""

I missed that part. Shame on Airbus then. Either they really believed
this and are thus stupid, or they were outright being deceptive.

I can't believe that their customers actually believed that though.
That is pretty amazing as well.


Matt

Thomas Borchert
November 23rd 05, 01:20 PM
Matt,

> I missed that part. Shame on Airbus then. Either they really believed
> this and are thus stupid, or they were outright being deceptive.
>

BS! I strongly suggest you read that report again. Nowhere does it say the
wake turbulence measurements have been completed and/or published. These
are "tentative" and "over-cautious" preliminary/interim standards issued
by ICAO as a suggestion. No one knows what wake turbulunce is causes - and
we will know before final ruling.

The problem is: The A380 is flying around as we speak, so ATC has to have
some guidance right now. That's what this does. It says NOTHING about the
actual wake turbulence caused.

But, anything for some cheap shots at Airbus, right?

--
Thomas Borchert (EDDH)

Skylune
November 23rd 05, 02:25 PM
by "Matt Barrow" > Nov 22, 2005 at 11:30 PM


"Peter R." > wrote in message
...
> Jay Honeck > wrote:
>
>> Airliners may have to fly twice the normal distance behind the new
>> Airbus A380 superjumbo jet to avoid potential hazards from its
>> unusually powerful wake, according to preliminary safety guidelines.
> <snip>
>
> Airbus should include color smoke generators off each wingtip to
colorize
> the vortices and give VFR aircraft something visually to avoid. :)
>

Different color smoke from each wingtip would be very pretty.<<

That would be cool, just like the stunt pilots' planes. Those jets would
look very cool doing hammerheads and loops to entertain the passengers and
crowds below.

Gail
November 23rd 05, 02:32 PM
>
> But, anything for some cheap shots at Airbus, right?


Here here!

The fact is that when Boeing launched the 747, the separation had to be
changed. No one seemed to mind to much that that happened at the time -
probably because of increased passenger volume.
With that in mind, what makes you think that airlines are going to mind too
much if the separation behind a 380 has to be increased? If the airbus
carries twice as many passengers, that effectively means less Boeings in the
sky and if there is less requirement for Boeings that means less a/c
pollution, more efficient ATC, and safer flying!

I shouldn't be cheering just yet if I were you...


:D


G

Frank Ch. Eigler
November 23rd 05, 03:24 PM
> > [...]
> > Airbus should include color smoke generators off each wingtip to colorize
> > the vortices and give VFR aircraft something visually to avoid. :)
>
> Different color smoke from each wingtip would be very pretty.

But imagine the mass of smoke agent that would have to be dispensed in
order for it to be visible 5-10 miles behind the jet. There would be
a terrific amount of dilution through the air, moving at that kind of
speed.

- FChE

Jay Honeck
November 23rd 05, 04:58 PM
> I shouldn't be cheering just yet if I were you...

Who was cheering?

I think the A-380 is very cool!
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

jbaloun
November 23rd 05, 06:21 PM
How about port side red smoke, starboard side green? Still smoke will
not show well. No point on night landings, just maintain increased
separation.

How about a ground based LIDAR to measure turbulence and/or windshear?
Then the localized air turbulence could be displayed in some of the
runway marker lights. Blink some of the lights in a pattern to indicate
the location of the turbulence or windshear or shifting
headwind/tailwind. The idea is some method of telling the pilots where
to watch out for turbulence of all kinds. There have been studies to
develop a LIDAR system on aircraft to watch for turbulence ahead. A
system on aircraft adds to the operating cost but is always available
to each plane so equiped. A system on the field would be available to
all planes but localized. On approach the pilot would have an idea of
how bad is the turbulence and whether or not to make a go-around. This
would only help on the field not on the approach or anywhere else. A
simple system would be a marker pattern that only indicates that there
is turbulence anywhere in the approach pattern but not any information
of specific location. This may be enough.

James

Matt Whiting
November 23rd 05, 08:04 PM
Thomas Borchert wrote:

> Matt,
>
>
>>I missed that part. Shame on Airbus then. Either they really believed
>>this and are thus stupid, or they were outright being deceptive.
>>
>
>
> BS! I strongly suggest you read that report again. Nowhere does it say the
> wake turbulence measurements have been completed and/or published. These
> are "tentative" and "over-cautious" preliminary/interim standards issued
> by ICAO as a suggestion. No one knows what wake turbulunce is causes - and
> we will know before final ruling.
>
> The problem is: The A380 is flying around as we speak, so ATC has to have
> some guidance right now. That's what this does. It says NOTHING about the
> actual wake turbulence caused.
>
> But, anything for some cheap shots at Airbus, right?

Well, if you are right, and I doubt it, that Airbus has no data on wake
turbulence either from CFD or wind tunnel tests, they they should not
have given ANY guidance to their customers about what it would be until
they did have some data.

Then again, you'll say anything if it takes a cheap shot at me.

Matt

Morgans
November 24th 05, 06:39 AM
"Frank Ch. Eigler" > wrote
>
> But imagine the mass of smoke agent that would have to be dispensed in
> order for it to be visible 5-10 miles behind the jet. There would be
> a terrific amount of dilution through the air, moving at that kind of
> speed.

Not to disagree with the fact that putting smoke systems on heavies would be
a bad idea, but I do wonder about how much smoke would have to be used.

I remember a few years ago at OSH, there was an older jet trainer (don't
remember which type) that had smoke generators carefully place on the
wingtips. The trail was tight, and spun fiercely for a very long time. ( 2
or more minutes?) I was fascinated.

Anyone else remember the details?
--
Jim in NC

G Farris
November 24th 05, 04:12 PM
In article >, says...
>
>
>Matt Whiting wrote:
>
>> And this is a surprise? Did they think an airplane that size would have
>> the wake turbulence of a 737?
>
>Not a 737, but Airbus was claiming it would be comparable to a 747, which is
>a "heavy" aircraft. If you read the article, you might have noted that
>
>"An Airbus A380 marketing brochure in 2003, for example, said: "there is
>no need to introduce any changes in separation standards" for the A380
>because the aircraft's wake "is similar to that of the 747-400.""
>


Yes, that has been the contention of the European consortium all along.
They claim that to be viable, the aircraft must be able to operate without
introducing any modification at all in spacing, and very little in runway or
ramp specifications. They will brand this press release suggesting the
contrary as Yankee anti-Airbus propaganda, spurred by the less technologically
advanced US aviation industry, who are fearful because they cannot compete
with the superior European industry.

GF

Ron Garret
November 24th 05, 04:56 PM
In article >,
"Morgans" > wrote:

> "Frank Ch. Eigler" > wrote
> >
> > But imagine the mass of smoke agent that would have to be dispensed in
> > order for it to be visible 5-10 miles behind the jet. There would be
> > a terrific amount of dilution through the air, moving at that kind of
> > speed.
>
> Not to disagree with the fact that putting smoke systems on heavies would be
> a bad idea, but I do wonder about how much smoke would have to be used.
>
> I remember a few years ago at OSH, there was an older jet trainer (don't
> remember which type) that had smoke generators carefully place on the
> wingtips. The trail was tight, and spun fiercely for a very long time. ( 2
> or more minutes?) I was fascinated.

That's actually what keeps the plane in the air.

See http://www.av8n.com/how/htm/airfoils.html#sec-circulation-vortices

rg

Morgans
November 25th 05, 04:22 AM
"Ron Garret" > wrote
>
> That's actually what keeps the plane in the air.

Very incompletely, and incorrectly stated.
--
Jim in NC

John Gaquin
November 25th 05, 05:28 PM
"Morgans" > wrote in message news:hschf.50
>
> .....had smoke generators carefully place on the
> wingtips. The trail was tight, and spun fiercely for a very long time.
> ( 2
> or more minutes?) I was fascinated.
>
> Anyone else remember the details?

Not that, but many times over the years I've crossed paths or trailed with
other a/c at a cruise altitude that generated contrails. Never saw the
other a/c, but could see their contrail still rotating as we passed. A
wingtip vortex starts out tighter, so may well last longer.

john smith
November 26th 05, 12:12 AM
In article
utaviation.com>,
"Skylune" > wrote:

> by "Matt Barrow" > Nov 22, 2005 at 11:30 PM
>
>
> "Peter R." > wrote in message
> ...
> > Jay Honeck > wrote:
> >
> >> Airliners may have to fly twice the normal distance behind the new
> >> Airbus A380 superjumbo jet to avoid potential hazards from its
> >> unusually powerful wake, according to preliminary safety guidelines.
> > <snip>
> >
> > Airbus should include color smoke generators off each wingtip to
> colorize
> > the vortices and give VFR aircraft something visually to avoid. :)
> >
>
> Different color smoke from each wingtip would be very pretty.<<
>
> That would be cool, just like the stunt pilots' planes. Those jets would
> look very cool doing hammerheads and loops to entertain the passengers and
> crowds below.

Who needs smoke when Mother Nature provides miles and miles (kilometers
and kilometers) of stratus clouds.

Capt.Doug
November 28th 05, 01:13 AM
>"Jay Honeck" wrote in message
> "will descend further
> and be significantly stronger" than those from other large jets,
> potentially even affecting jets traveling in the opposite direction
> some 2,000 feet below.

Who's authors haven't heard about RVSM- ICAO's or WSJ's?

D.

David CL Francis
November 28th 05, 11:54 PM
On Thu, 24 Nov 2005 at 08:56:56 in message
>, Ron Garret
> wrote:

>That's actually what keeps the plane in the air.
>
>See http://www.av8n.com/how/htm/airfoils.html#sec-circulation-vortices
>
>rg

That is a good article. I would partially disagree in that he minimises
viscosity of the air as a factor. True it is small, however if the air
had no viscosity then there would be no circulation and hence no lift.
He actually shows diagrams without circulation which produce no lift.

The necessity of viscosity was demonstrated by Jean le Rond d'Alembert.
In fact he did painstaking mathematics, without recognising viscosity,
and failed to be able to show why there should be any forces on a body
in an airflow at all. He went to his grave a puzzled and dissatisfied
man.

That is d'Alembert's Paradox.
--
David CL Francis

November 29th 05, 02:50 AM
I know the jet you're referring to but can't remember it... however, I
do also remember that Herb Baker's T-28 has exactly the same system and
you can see a video of it here:

http://herb-ditto.com/Herb.wmv

It makes for a very cool display.

john smith
November 29th 05, 04:14 AM
In article . com>,
wrote:

> http://herb-ditto.com/Herb.wmv

Nice promo video.

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