A-380 separation problems

Skip Miller

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Skip Miller
From the Wall Street Journal:

"Airbus A380 Faces Operating Limits
Extra Restrictions on Big Jet
Owing to Its Powerful Wake
Are Likely to Remain Awhile
By ANDY PASZTOR and DANIEL MICHAELS
June 12, 2006; Page A3

The Airbus A380 airliner, already buffeted by years of production and development headaches, is likely to face a daunting challenge once it enters service next year: unprecedented operating restrictions intended to protect nearby aircraft from flying into the air turbulence churned up by the superjumbo jet.

Rules that include special flight restrictions and extra spacing could pose an immediate marketing problem for Airbus because other planes in the A380's vicinity will likely have to either slow down or wait longer to take off to allow for the additional distance. Airbus designed and marketed the $300 million plane amid promises that it would fit seamlessly into existing global air-traffic patterns.

International aviation regulators and aerodynamic experts failed again last week to reach a consensus about the extent of the safety hazards created by the A380's unusually powerful wake, according to people involved in the deliberations. Meeting behind closed doors in Montreal, a study group including U.S. and European government officials continued to disagree about permanent safeguards to ensure that turbulence created by the A380 won't affect airplanes during takeoff, cruising and landing. In extreme cases, such turbulence is capable of wrenching even a large jetliner out of control.

Without a set of permanent standards, some version of the strict interim guidelines now in effect -- requiring at least twice the normal in-flight separation when trailing the twin-deck Airbus model -- likely will stay in place until well into 2007. Barring a last-minute breakthrough, these people said, this means that the world's largest passenger aircraft is poised to begin service with significantly more-stringent separation rules than any other jet.

Airbus has touted the 555-seat A380 as "the economical solution for heavily traveled routes." But the interim guidance from the International Civil Aviation Organization calls for minimum separations of 10 nautical miles for all aircraft following a landing A380, compared with the typical five miles required when following 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. A further complication is that controller organizations previously warned they may need as long as nine months preparation time to phase in new standards.

Airbus, which is 80%-owned by European Aeronautic Defence & Space Co. and 20%-owned by Britain's BAE Systems PLC, declined to comment on the turbulence issue. Some Airbus officials recently have expressed a willingness to accept a modified version of the present standards as a first step -- with the understanding that permanent rules would follow relatively quickly. The scientific work initially was supposed to be finished around the start of this year, but verifying certain computer-modeling techniques has been especially tough.

The strength of a wake depends partly on the weight of the aircraft that produced it. Wind and weather conditions can make turbulence hard to measure accurately around airports. Turbulence levels are also particularly tough to evaluate while a jet is climbing or cruising at high altitudes.
Since the controversy erupted last year, Airbus has invested millions of dollars and months of extensive flight tests to try to demonstrate that the wake of the 500-ton A380 poses no greater potential safety threat than turbulence generated by Boeing's largest model, the 747, which weighs about 100 tons less. There haven't been any recent crashes of jetliners attributed primarily to wake encounters, though over the years some business and private planes have experienced serious incidents and even crashed after following a larger aircraft too closely near an airport.

Industry and government officials on both sides of the Atlantic increasingly predict that Airbus will be forced to accept different rules than it anticipated. Andre Auer, head of the Joint Aviation Authorities, a European umbrella group with some regulatory responsibilities, said in an interview days before last week's Montreal sessions that the interim guidelines for the A380 "are likely to stay in place until commercial service starts."

The ICAO, which issued the preliminary safety standards in November, confirmed that no final agreement has been reached. The study group is interested in "harmonizing the new specifications, whatever they may be," so they apply equally all over the world, said spokesman Denis Chagnon. He added that the study group "is working well together" and hopes to issue a report in mid-November that ICAO officials could then review.

Privately, even some Airbus officials predict the A380 temporarily may have to be put into a new air-traffic-control category, until its safety is proved in actual conditions.

The A380 has faced other head winds, including a six-month production delay. Separately, engineers were recently forced to reinforce some structural elements inside the wings after they fell short on a stress test in February."

-Skip
 
What about those massive Antonov transports? How much do they weigh, and what are their standards?
 
flyingcheesehead said:
What about those massive Antonov transports? How much do they weigh, and what are their standards?

IIRC something like 1.3 million lbs GW.

The average airline isn't exactly going to be trying to cram as many of them as possible into any given airport during rush hour.
Oddball transports are one thing to fit in on the very rare occurance. Daily nose to tail cattle cars are another.

Reinventing the wheel, or in this case, wing again...Instead of building a new big monster, maybe they should have just bought a mess of AN 225's. I think it's GW and useful load is higher and can carry whatever will fit throught the gaping hole in the front up to and including locomotives. Just slap in a bunch of seats and carry a bigger small city full of people. It would probably be easier and quicker to load 1000+ people through the gaping hole in the front anyway.
 
Interesting Skip. I posted this over on AvSig so the guys there could see it; hope you don't mind.

Could help some GA guys do their first roll!


Best,

Dave
 
Some data from the 70's... I think the 2707 was going to be the American SST...
 

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Dave Siciliano said:
Interesting Skip. I posted this over on AvSig so the guys there could see it; hope you don't mind.
I don't, thanks.
Could help some GA guys do their first roll!
Note to self: When operating in Class B and it gets real dark on a cloudless day, tighten belts! :D

-Skip
 
I wonder, since an airframe like this will generally be used on higher density flights (i.e. transatlantic, transpacific, etc), if the airlines will circumvent this problem all together and send these planes on those routes at "unfavorable" times. They could create pricing structures to incent travellers to travel off-peak and kill two birds with one stone - justify the investment, reduce gate congestion at critical times.

Cheers,

-Andrew
 
More perspective on the issue:


WELL: Here's what the Society of British Aerospace Companies has to say about it:

"USA - San Francisco Airport Set for the Big One
20/01/2006 10:28:49



SAN FRANCISCO - With ample seating in its spacious international terminal
and six gates equipped for doubledecker jets, not to mention a fine
selection of restaurants, this city's airport is ready for the massive
555-seat A380 airliner.

LAX has none of the above.

While Southern California officials dickered during the last decade about
how to modernize Los Angeles International Airport, San Francisco built a
gleaming $1-billion international terminal that was specifically designed to
accommodate the new Airbus super-jumbo jet. The world's largest passenger
plane is expected to start service to the West Coast in spring 2007.

The stark contrast between San Francisco International Airport and LAX -
which plans to modify two gates for the double-decker plane at the already
cramped Tom Bradley International Terminal - has led to speculation that San
Francisco will woo A380 flights away from LAX.

"If airlines feel like they are not going to be able to be accommodated,
then they'll start looking at other airports," said Allan McArtor, chairman
of Airbus North America. McArtor met last week with Mayor Antonio
Villaraigosa and airport officials to urge them to move ahead with plans to
modernize LAX so it will retain its status as the gateway to the Pacific
Rim.

"It's no secret that San Francisco is delighted to entertain any of these
carriers," McArtor said. "Once they move there and get the maintenance and
the ticket counters and ground handling, it's very difficult to get that route back."
 
This would require a major shift in airline operating philosophy, if history is any indication. Airlines schedule to catch the full fare business traveller as often as possible, i.e. 7-9am and 5-7pm departures. I don't think that will change any time soon. There's already discounts in place for "off-peak" flights with lousy connections.

astanley said:
I wonder, since an airframe like this will generally be used on higher density flights (i.e. transatlantic, transpacific, etc), if the airlines will circumvent this problem all together and send these planes on those routes at "unfavorable" times. They could create pricing structures to incent travellers to travel off-peak and kill two birds with one stone - justify the investment, reduce gate congestion at critical times.

Cheers,

-Andrew
 
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