Aircraft

GE Aviation believes tests it has already conducted with SAS in Stockholm in optimal trajectory descent management are easily adaptable to carriers that now use its flight management system.

The company's FMS is standard for all Boeing Classic and Next Generation 737s. Through a partnership with Thales, GE offers an FMS for Airbus aircraft. Airbus is close through a software change to adopting the four-dimensional trajectory operations demonstrated by SAS on 737s that showed an average record fuel savings of 240,000kg (530,000lb) and carbon dioxide reduction of 756t in more than 4,000 approaches using an idle thrust performance path developed by the FMS.

"We have powerful existing equipment to exploit for development of noise reductions and emissions in short order for the mid-term," says Keith Wichman, chief engineer of flight management systems at GE Aviation.

Through the use of current aircraft communications addressing and reporting system (ACARS) functionally that liaises with the FMS for communication with air traffic control, GE has already proven the ability to reduce track distances in descents, perform required time arrivals down to the runway and manage aircraft sequence spacing.

Beginning at the top of descent, the FMS computed descent path allows controllers to manage two aircraft projected to arrive at the same time by assigning a new time to the FMS-equipped aircraft if necessary while controllers can focus on vectoring an unequipped aircraft.

For the time being Wichman says ACARS has adequate capability to support the four-dimensional trajectory operations supported by the GE FMS system.

By showing the early benefits of trajectory management Wichman says experience gleaned from those operations can supply standards bodies with necessary information to develop long-term solutions.

But in the short term, GE Aviation is "excited about taking what we know the aircraft can do on the ground side" and extracting value from that, explains Wichman.

He says US operators look at the accelerated progress of NextGen in regions such as Australia and Europe and pose the question: "Why can't we see that here?"