A joint effort by the FAA and industry aimed at integrating airspace and deconflicting traffic flows over major metropolitan areas is making progress, according to participants.

Study teams have completed work at the first two of 21 identified “metroplex” sites–metropolitan areas with multiple airports and municipalities–designated by the FAA through the Optimization of Airspace and Procedures in the Metroplex (OAPM) initiative.

With the study phase completed, the Washington, D.C., and North Texas metroplex projects, considered prototypes, will transition to a design and implementation phase that could see airspace changes introduced by 2013.

Metroplex study teams focused on Charlotte, N.C., and Northern California are nearing completion. Study projects in Houston, Atlanta and Southern California will begin by this summer.

OAPM study teams consist consist of FAA subject-matter experts, Mitre specialists, contract administrative support personnel and representatives of airlines and the National Air Traffic Controllers Association (Natca). Their objective: analyze operational challenges in their regions, assess planned and potential new solutions and make recommendations that will be advanced by the design and implementation teams.

“What really makes this effort stand out is that the study teams are professional teams; they have been trained for this process,” said Capt. Brian Townsend of US Airways Flight Technical Operations.

“One of the main goals is to deliver a consistent product throughout the NAS,” explained Townsend, who is involved in the Washington, D.C., metroplex project. “When the study teams come in, we’re able to sit down with the facilities and also with the other stakeholders and identify what the current issues are in their airspace, what’s working, what’s not, and also what plans they already have under way. The study teams are not there to derail any ongoing efforts, but it’s to understand the entire metroplex area and where there’s conflicting traffic.”

Lyndon Bertke, Cincinnati Tracon and tower support manager and FAA subject-matter expert on the Charlotte OAPM team, described a study process as akin to concentric circles emanating from Charlotte Douglas International Airport.

“For Charlotte, which is the single big air-carrier airport in the middle of the approach control…we go in and we start looking at the procedures into and out of the airport, and try to optimize all the procedures into and out of Charlotte,” Bertke said. “Of course, whenever you change one thing at a big airport, especially in the East or Southeast, it begets changes to other facilities. So we spread out and started looking at some of the satellite airports that are in Charlotte’s approach control airspace. We try to optimize those based on the optimization we’ve done with Charlotte.”

Added Rock Brown, a front-line manager at the Houston Air Route Traffic Control Center (ARTCC) and a Charlotte OAPM subject-matter expert, “One of our big objectives was to optimize without doing harm to any associated flows.”

The resulting set of recommendations from the study teams “provides a basic consensus and buy-in before we get to the design and implementation teams,” Townsend said. The design and implementation process for each metroplex site is expected to take up to three years before new procedures are published.

NextGenRoots

The metroplex effort stems from deliberations of the RTCA NextGen Mid-Term Implementation Task Force, or Task Force 5, an industry and government collaboration started in 2009 to develop industry-consensus recommendations on implementing NextGen operational efficiencies by 2015. The process involved some 300 aviation industry stakeholders.

Task Force 5 produced a list of suggested operational capabilities in the domains of surface operations, runway access, metroplex operations, cruise and general aviation access to the National Airspace System. A major theme of the recommendations, which the FAA subsequently incorporated in its NextGen Implementation Plan, was that early NextGen efficiencies can be achieved using currently available aircraft equipment and airspace procedures.

Metroplex sites were chosen based on FAA-developed criteria and in collaboration with the RTCA NextGen Advisory Committee.

True to the spirit of Task Force 5, the OAPM study teams are relying on current aircraft navigation capabilities to enhance airport arrival and departure paths, provide more diverging departure paths to get aircraft off the ground more quickly, and add more direct, high-altitude Rnav navigation routes between metroplexes.

Grady Boyce, Delta Air Lines technical pilot, said he has been asked if metroplex study teams are looking into NextGen procedures and systems such as trajectory-based operations, automatic dependent surveillance-broadcast (ADS-B) and data communications.

“No, we’re looking at using today’s tools–TMA [traffic management advisor] and timing and basic Rnav,” Boyce said. “In direct response to the Task Force 5 report, these metroplex teams are looking at developing something that can happen in the next couple of years. It’s important to understand that we are looking at technology that exists today on the airplane, finally bringing that to bear to the system. There is an eye to future technologies–what will data com do, what will ADS-B do–but it is not germane to the immediate task.”

Rnav is a performance-based navigation (PBN) approach allowing aircraft to fly a desired course within coverage of existing ground or GPS navaids. In the case of the Washington, D.C., metroplex, several existing RNAV standard instrument departures (SIDs) and standard terminal arrival routes (Stars) would be modified; others would be created. However, more demanding PBN procedures such as required navigation performance, authorization required (RNP AR), which is GPS-specific and necessitates onboard course monitoring and alerting, are also being proposed, for example by the North Texas study team at Dallas Love Field.

“In Dallas, we looked at some RNP procedures into Dallas Love just because of constrained airspace and Southwest’s [RNP] equipage rate,” said Dennis Zondervan, with the Mitre Center for Advanced Aviation System Development. “But basically we’re looking at things we can implement in two to three, maybe five years at the max.”

Significant Savings

According to a February presentation by Elizabeth Ray, FAA vice president of Mission Support, adopting changes recommended by the Washington, D.C., metroplex study team would produce $6.4 million to $19 million in fuel savings resulting from optimized profile descents and reduced track distances. Additional benefits would be reduced radar vectoring and controller task complexity, “repeatable, predictable flight paths” and reduced need for traffic management initiatives (TMIs) such as ground delay programs.

Changes recommended for the North Texas metroplex, which include the introduction of ultra-high sectors above 35,000 feet managed by the Fort Worth ARTCC, would produce annual fuel savings of $10.3 million to $21.7 million, with additional benefits, according to the Ray presentation.

Capt. Ken Spier, director of line operations with Delta Air Lines in Atlanta, said it is important to “stay the course” with the OAPM effort to demonstrate operational efficiencies that can be achieved now, before the investment in equipment that NextGen will require.

“This system is for all users, it’s safe, but change comes slowly,” Spier said. “The realities of the system make it difficult to justify a business model from an avionics perspective. It takes the whole model to really crack that chicken-and-egg scenario that we’ve got in place.”