ATM Modernization, Commercial

NextGen Special Section: Stacking Up SESAR, NextGen

By Frank Alexander | January 1, 2010
Send Feedback

The origins of the Single European Sky ATM Research (SESAR) program and RTCA’s NextGen Mid-Term Implementation Task Force, or Task Force 5 (TF5), differ significantly in that SESAR originated as a result of legislation created by the European Commission in 2004. It established a political framework for the development of an advanced air-traffic management environment that would support the doubling of capacity by 2020.

TF5 began with a request from the chief operating officer of FAA’s Air Traffic Organization and associate administrator for Aviation Safety, asking that a task force be formed to "establish a community-wide consensus on the NextGen operational improvements to be implemented during the transition between now and 2018."

The key difference between SESAR and TF5 is that SESAR encompasses the full range of research, development, regulations and implementation of changes to European airspace from the present to 2020 while TF5 is primarily focused on the implementation of operational capabilities that are achievable up to 2018.

SESAR is broken down into three major phases: Definition, Development and Deployment. The Definition Phase (2005-2008) was managed by the Air Traffic Alliance, a grouping of EADS, Airbus and Thales, and developed by a representative group of stakeholders consisting of more than 30 operators, Air Navigation Service Providers (ANSPs), airports, airlines, Eurocontrol, Airbus, avionics OEMs and air-traffic management (ATM) providers. It defined the system performance requirements to and beyond 2020, established a Master Plan for research, technology and validation programs and proposed legislative, regulatory and financial frameworks for its implementation.

The SESAR Master Plan identifies three Implementation Packages (IP). IP1 consists of existing R&D programs that are ready for short-term deployment. IP2 addresses R&D for mid-term deployment, and IP3 encompasses R&D for the far term. Each IP is also further defined in terms of Level of Service and Level of Capability.

Develop and Deploy

The Development Phase (2009-2014) is managed by the SESAR Joint Undertaking, led by the European Commission and Eurocontrol with contributions from industry partners. During this time, work will be done to develop and validate the IP2 concepts for the deployment phase and to generate the regulatory framework to support the proposed changes to the airspace system. In addition, research will be performed on IP3 long-term concepts.

Finally, the Deployment Phase will begin around 2015. During this timeframe, most of the technological advances will be phased into the system. In parallel, the European Commission will begin deploying IP1.

The RTCA NextGen Mid-Term Implementation Task Force report, issued Sept. 9, provided recommendations to FAA intended to focus on the near and mid-term timeframes extending out to 2018. The recommendations adopted by FAA will be incorporated into the next editions of the NextGen Implementation Plan and Enterprise Architecture that serve as the planning documents for improvements to the U.S. National Airspace System. Changes adapted to these documents will be made in the first quarter of 2010.

Both programs have support from their respective user communities and include implementation plans for operational capabilities of both aircraft and the ATM system. They also include financial analysis, incentivization, research and post implementation analysis. The operational capabilities are similar, differing mostly in terminology, though SESAR seems to place greater emphasis on capabilities of the ATM system than on the aircraft and its avionics, especially during the period up to 2013. TF5 recommendations are more heavily dependent on aircraft and avionics capabilities, policy changes and an emphasis on greater use of Area Navigation (RNAV), Required Navigation Performance (RNP) and Vertical Navigation (VNAV)-based flight profiles.

Some of the more notable differences between SESAR and the TF5 Report include the fact that SESAR’s scope is larger than that of TF5, reaching much deeper into the areas of research, airspace management, institutional issues, safety management, environmental and human factors, among others. The European enroute airspace structure is completely RNAV-based (RNAV-5) while U.S. enroute airspace is largely conventional, using ground-based navigation aids to define the routes.

Conversely, the United States has moved aggressively in developing significant numbers of terminal RNAV procedures using RNAV-2 and RNAV-1 while Europe has been somewhat slower to introduce Precision-RNAV (RNAV-1) into their terminal management areas (TMA).

The United States has a large number of RNAV and increasing number of localizer performance with vertical guidance (LPV) approach procedures as well as RNP Authorization Required (AR) approach procedures. RNAV, LPV and AR procedures have not evolved as quickly in Europe.

Another significant challenge in Europe will be coordinating the activities of the European Union member States together with neighboring non-member states.

Europe is utilizing an Enhanced Mode-S surveillance system to supplement its existing secondary surveillance radar (SSR). The U.S. surveillance system is expected to remain primarily SSR-based with a phasing in of Automatic Dependent Surveillance-Broadcast (ADS-B) capabilities beginning in 2013 when the ground system is expected to be operational.

A European Notice of Proposed Rulemaking has been issued calling for all operators to be equipped with ADS-B transponders by 2015. An exemption will be granted for all aircraft weighing less than 12,500 pounds and with a cruise speed of less than 250 knots. This is five years earlier than what has been proposed by FAA. Also of interest is the fact that the European notice does not require the same performance values that are expected to be proposed by the FAA ADS-B rule although the DO-260B transponder standard is expected to be the same.

Datalink Communications

Europe has taken a more aggressive position on the use of ATC datalink communications. It has established a mandate for the use of ATN Controller Pilot Data Link Communications (CPDLC) for all new aircraft (forward fit) delivered after Jan. 1, 2011. By 2015, all aircraft operating in the core of Europe will be required to have datalink communications capability. The baseline for the data link will be the ATN protocol, however, there are provisions to allow the use of FANS-1/A during a transition period that has not yet been defined.

By Feb. 7, 2013, all state ANSPs participating in the Link 2000+ program must have an operationally compliant ATN data link system ready for use.

The SESAR implementation plan and the TF5 recommendations focus on the initial application of trajectory-based operations, approach and landing operations, surface safety and efficiency. Both place emphasis on the near-term utilization of existing aircraft and avionics capabilities and support the early use of basic levels of collaborative decision-making and information sharing. SESAR also focuses on continuing research and policy development for advanced capabilities beyond the midterm. The TF5 report does make recommendations for future research but not to the depth as that included in SESAR.

During the near- and mid-term timeframes, SESAR and TF5 support the greater use of expanded RNAV terminal procedures, Continuous Descent Approaches, Continuous Climb Departures, surface movement safety and awareness, and traffic flow management. SESAR also will implement runway occupancy reduction techniques and as mentioned earlier, will provide for the implementation of datalink services for routine ATC communications.

The TF5 report places a great deal of emphasis on further development of closely spaced parallel runway procedures, both arrival and departure. Recommendations to FAA in this area include changes to current policy to enable the simultaneous use of RNAV/RNP approaches in parallel operation with ILS procedures, revision of the blunder assumptions that have established the current minimum runway separation requirements for simultaneous parallel approach operations and changes in policy that would allow simultaneous RNAV/RNP departure procedures without requiring an initial heading to ensure course divergence.

These are viewed by American operators as having significant operational benefits with little or no modification to existing aircraft capabilities. SESAR does not appear to address this capability during the near and mid-term time frames.

In summation, both SESAR and the RTCA NextGen Mid-Term Implementation Task Force report address the need to expand and improve their respective air-traffic infrastructures. The methodologies differ somewhat as do some of the desired timeframes. Both strive to meet the goals of their respective user communities and service providers and both agree that interoperability is an essential piece of ensuring success.

The TF5 report stresses maximum improvements at minimum cost to the operators initially, but acknowledges that changes in equipage will be needed to further improve the system. SESAR places a greater emphasis on ATM operations and procedure enhancements in the near and mid-term and will require the mandate of upgraded avionics capability (datalink and ADS-B) to achieve some of the expected improvements.

European Airlines, Business and GA Join SESAR Program

The SESAR Joint Undertaking in September signed contracts with several European airlines, the International Air Transport Association (IATA) and organizations representing business and general aviation to participate in the SESAR Development Phase.

The Brussels-based public/private organization, tasked with managing the multi-year development phase, announced agreements with Air France and its subsidiary Regional, KLM, Iberia, Lufthansa Group, SAS Scandinavian Airlines, TAP Portugal, Novair and IATA. Also signing on to the effort were a consortium coordinated by the European Business Aviation Association, including NetJets Europe and Dassault Aviation, and the International Aircraft Owners and Pilots Association.

"It is essential or even vital for the success of SESAR that the expertise of the airlines is integrated as from day one of the development phase," said Patrick Ky, SESAR JU executive director. "They will participate and analyze the outcomes of the SESAR projects from technical and cost perspectives, which will reinforce the user-driven approach of the future SESAR technologies and procedures."

The organization said it requires technical support in the areas of flight operations, in particular fuel efficiency; flight-planning processes and supporting systems; avionics system specifications; operations and control processes; data link; aircraft scheduling and network management; crew training and cost and revenue evaluation.

Last June, the SESAR JU announced contracts with 16 industry partners, including Thales, Honeywell, air navigation service providers, airports, airframers and ground equipment firms.

Receive the latest avionics news right to your inbox