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Old 03-06-2006, 04:14 AM
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captjns
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Default Controled Decent Approaches

UPS plans to reduce noise from landings Technique to provide relief 7 to 30 miles out

By Wayne Tompkins
[email protected]

The Courier-Journal

UPS plans to phase in a quieter, more environmentally friendly landing technique this spring at its cargo hub at Louisville International Airport.

The continuous descent approach, sometimes called the "green" approach, is designed to save fuel and provide relief from aircraft noise to people living seven to 30 miles from the runways. During tests conducted with UPS jets in 2002 and 2004, continuous descent cut aircraft noise up to 50 percent in such areas while saving as much as 500 pounds of fuel per flight.

Continuous descent, which has become a safe, feasible option because of new technology planned for the cockpit, reduces noise by keeping the Boeing 757s and 767s higher in the air for a longer time before they make their final approaches. Planes that now descend and level off at 3,000 feet for the last several miles to the airport will not be that low until closer to the runway under the new approach.

"This will provide relief because this will keep aircraft higher, longer, farther out from the airport," said Rande Swann, spokeswoman for the Louisville Regional Airport Authority. "This is not the (noise) solution for the immediate airport neighbors as much as … a solution for people on the periphery." Under Federal Aviation Administration rules, landing operations and procedures during the last seven miles cannot be altered for safety reasons. The exact date that UPS will start using continuous descent has not been set. The FAA said last month that it needs to conduct further reviews before signing off on UPS' plans.

The technique will have economic implications beyond Louisville. The aviation industry is watching continuous descent closely, hoping its promise of noise reduction softens resistance to airport expansion and construction projects it says are needed to reduce congestion.

And fuel savings would be an obvious benefit for financially strapped airlines. A UPS shift to continuous descent should provide noise relief for residents in Southern Indiana, which the jets pass over between midnight and 2 a.m. The elevation of some of those communities -- nearly 900 feet higher than Louisville's -- compounds the noise problem, according to a 2002 study by the Massachusetts Institute of Technology.

The last 15 of about 100 early morning UPS flights will use the procedure during the evaluation period. Those flights land between 1:45 and 2:30 a.m. "If we show it can be done here, then it can be spread throughout the United States and around the world," said Capt. Bob Hilb, a veteran UPS pilot who has been involved in continuous-descent testing.

Under the current system, jets cruising at 3,000 feet generate noise over areas as far as 30 miles from the airport. That's because planes must increase engine power (and fuel consumption) to maintain altitude.
In contrast, planes on a continuous-descent approach don't cruise. They follow a direct path for most of the landing -- spending most of that time higher in the air until final descent .

For safety reasons, UPS planes using the new approach initially will be spaced farther apart as they line up to land. Later, as new equipment using global positioning systems enters the cockpit, pilots will be able to return to the current spacing, said Hilb, the UPS pilot.

Hilb said continuous descent could not be used before because air densities and wind speeds change as a plane descends, making it difficult for air-traffic controllers to keep planes at the same speed and distance from one another.

But spacing the planes farther apart would delay cargo-sorting operations. Since the new cockpit equipment will give pilots a precise look at where they and the aircraft around them are located, UPS says its planes will keep their current spacing even when using continuous descent. The new technology also will enable planes to stay on the same landing path. "This allows us to more precisely direct the aircraft to the airport, take advantage of the less-populated areas below and decrease aircraft noise for more people," said Swann, the airport spokeswoman. "Before, if you looked at the flight pattern, they (the aircraft) were all over the place. So everybody was getting noise at some time or another."

The phase-in of the new landing approach will be coordinated so as not to cause delays at UPS' package-sorting operation at its Worldport hub, company spokesman Mark Giuffre said. Eventually, Hilb said, planes should be able to reach the runway and taxi to the hub more quickly than under the current landing system.

http://www.courier-journal.com/apps/...603050376/1003

This CDA policy has been in place and in practical use around the world for many years... even while not an actual FAA procedure, its been used in the US at a number of airports for many years too. During step down descents many of us control our descent using "VERT SPEED" at a rate to join the G/S about 5 to 10 mile out from landing, thus reducing fuel consumption and noise.

This type of descent profile has been used by a B727 operator that I flew for going back 8 years ago in order to stay as noise friendly as possible with late night operations... Oh yeah... avoid the noise meters. The FAA has been approached by many carriers and the ASF over the years outlining programs in place with other countrys' aviation agencies. Other countries have the CDA planned to a science, with 10 to 15 mile seperation during the descent and initial approach phase and about 5 mile separation between final approach and landing aircraft... very precise and impressive. Controllers using the CDA program provide velocity, vertical and lateral vectoring with advisories on track distance to touchdown for configuration planning. Congradulations to the dedicated group at UPS that are reopening and spearheading the CDA program. Hopefully, the FAA will formally implement the CDA procedure as many agencies around the world has already.

Last edited by captjns; 03-06-2006 at 04:32 AM.
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