Airports referenced in this story
- Improved Approaches and Low-Visibility Operations (IALVO)
- Outlines ways to increase access and flexibility for approach operations through a combination of procedural changes, improved aircraft capabilities and improved precision approach guidance.
The sun shines even brighter at sunny Phoenix Sky Harbor International Airport thanks to fuel-efficient NextGen arrival procedures that are not only easing congestion, but also providing a smoother ride for passengers.
The FAA has converted Sky Harbor's four primary arrival routes into Optimized Profile Descents (OPD), which means that aircraft begin a smooth glide from high altitude airspace using minimal engine power instead of approaching the airport in the conventional, stair-step fashion. Think of it as sliding down a banister rather than walking down the stairs. The conventional approaches burn more fuel and create more noise because aircraft have to power up engines and deploy air brakes as the aircraft make the series of steep descents followed by periods of level flight.
Efficient and environmentally friendly flight operations come as good news to air carriers and passengers flying into Phoenix. Sky Harbor is one of the ten busiest U.S. airports for passenger traffic, with more than 100,000 passengers arriving and departing the airport on a typical day. The airport handles more than 1,200 aircraft operations a day and more than 800 tons of air cargo passes through the airport daily.
US Airways, which uses Sky Harbor as one of its hubs, estimates it burns less fuel at Sky Harbor compared with its other hub airports, saving 500 pounds of fuel per OPD arrival, said David Surridge, US Airways manager of Flight Operations Policy and Procedures. Given the airline has 180 Sky Harbor arrivals per day, the OPD fuel savings adds up to $14.7 million per year, he said.
Fuel savings also mean less aircraft exhaust emissions. By flying OPDs into Sky Harbor, US Airways reduces its carbon footprint by 51,000 tons per year, Surridge said.
"The fuel savings achieved at Phoenix are the model for the rest of the National Airspace System and clearly show what benefits can be achieved with these futuristic procedures right now," said Curt Faulk, the FAA manager who oversaw the implementation of OPDs at Phoenix.
OPDs are an integral part of the FAA's airspace modernization effort to improve safety and make air travel more efficient. These new types of procedures provide a sharp contrast to the way aircraft have previously operated. With conventional approaches, air traffic controllers guide aircraft by assigning a series of turns and descents that require constant conversation with the pilots. With OPDs, controllers give pilots one clearance to begin the descent. That clearance may be the only needed conversation between controllers and pilots until the aircraft is on final approach to land. All the other directions pilots need are on a chart they review in the cockpit.
Brian Townsend, a US Airways flight technical operations pilot who is helping the airline transition to NextGen operations, can attest to that.
When flying OPDs into Phoenix, Townsend and his aircrew often receive their descent clearance when they are as much as 150 miles from the airport. If there are no traffic conflicts or weather issues, the next radio conversation with a controller is often on the final approach just before receiving landing clearance, allowing Townsend and his co-pilot more time to spend on the numerous other cockpit duties required when arriving at a major airport.
The reduction in pilot-controller radio transmissions is significant. "In some cases, by probably up to 40 percent," said Faulk. "There is a tremendous positive safety benefit from this through the vast reduction in opportunity for what we call read-back/hear-back errors," he added. Read-back/hear-back is when the controller reads an instruction to the pilot and the pilot reads it back to the controller to ensure that it is fully understood. If the pilot gets it wrong, the procedure has to be repeated.