Improved Multiple Runway Operations improves runway access through the use of improved technology, updated standards, safety analysis and modifications to air traffic monitoring tools and operating procedures that will enable more arrival and departure operations.
Phases of Flight
Timeline for Achieving OIs and Capabilities
1 Formerly OI 104109: Current Arrival/Departure Sequencing.
Selected Work Activities
1 OI 102140: Wake Turbulence Mitigation for Departures (WTMD): Wind-Based Wake Procedures (2011-2016)
- Supported by NextGen Flexible Terminal Environment
- Completed: Reviewed safety risk management document
- Initiate controller training in preparation for WTMD operational prototype demonstration at
- WTMD Installation at
- Complete Data Collection of WTMD at
- WTMD operationally available at
2 OI 102141: Improved Parallel Runway Operations (2012-2018)
- Supported by NextGen Flexible Terminal Environment
- Completed: Reviewed safety risk management document on proposed standards for independent runway separation
- Completed: Expanded the application of FAA Order 7110.308 at
- Completed: Completed Blunder Model Revision
- Complete document change proposal for reduced standards for dual simultaneous independent parallel instrument approaches in Order 7110.65
- Complete safety study for reduced separation standards for simultaneous dependent parallel approach
- Investigation of next Order 7110.308 sites:
- Complete safety assessment for Wake Turbulence Mitigation for Arrivals-Procedures (WTMA-P) for Heavy/B757
- Review safety risk management document on proposed standards for simultaneous dependent parallel approach
- Complete Safety Analysis for reduced separation standards for simultaneous independent parallel approaches – dual with offset
- Complete Safety Analysis for reduced separation standards for simultaneous independent parallel approaches – triples
3 OI 108209: Increase Capacity and Efficiency Using Area Navigation (RNAV) and Required Navigation Performance (RNP)
- Supported by Operations Appropriations
- Completed: Developed Converging Runway Display Aid (CRDA) training program for air traffic control specialists
Descriptions of OIs and Capabilities
at least one site
WTMD: Wind-Based Wake Procedures
Changes to wake rules are implemented based on wind measurements, allowing more closely spaced departure operations procedures to maintain airport/runway capacity. Procedures are developed at applicable locations based on the results of wake measurements and safety analyses using wake modeling and visualization. During peak demand periods, these procedures allow airports to maintain airport departure throughput during favorable wind conditions. A staged implementation of changes in procedures and standards, as well as the implementation of new technology, will safely reduce the impact of wake vortices on operations. This reduction applies to specific types of aircraft and is based on wind transporting an aircraft's wake away from the parallel runway's operating area.
Task Force: Runway Access
Additional 7110.308 Airports
This increment provides airports with maximum use of closely spaced parallel runways by authorizing participating aircraft to operate at reduced lateral and longitudinal spacing on dependent, instrument approach procedures to runways with centerline spacing less than 2,500 feet. This increment will expand the application of FAA Order 7110.308 beyond the locations and runway ends already approved, and implement this capability using available ground and airborne equipment, existing displaced runway thresholds, historical wind data and procedural modifications to instrument approach procedures to maximize the reduced separation benefit.
Task Force: Increase Use of Staggered Approaches (12)
WTMA-P for Heavy/B757 Aircraft
This increment allows heavy and Boeing 757 aircraft to lead a dependent, staggered instrument approach procedure to closely spaced parallel runways at spacings less than the single-runway separation used today. This will increase the efficiency of runway throughput at approved airports. Operational availability is planned for 2014-2015.
Implement Satellite Navigation (SATNAV) or Instrument Landing System (ILS) for Parallel Runway Operations
This increment will enable policy, standards and procedures to allow use of SATNAV or ILS when conducting simultaneous independent and dependent instrument approaches, and implement this new capability at approved locations. The current standard for parallel approaches relies on ILS for simultaneous independent and dependent approaches. This increment expands this capability by implementing both unaugmented GPS-based approaches, such as RNAV (GPS), and RNAV RNP, as well as Wide Area Augmentation System-augmented GPS-based approaches, such as Localizer Performance with Vertical Guidance (LPV) and Ground Based Augmentation System Landing System (GLS), for these parallel approach applications. This provides more options for air traffic control and users during Instrument Meteorological Conditions (IMC). Further research and evaluation of GLS approaches is required, but their inclusion in a future update to FAA Order 7110.65 is expected. These additional options increase the chance of maintaining higher throughput when needed to support demand.
This improvement will increase access to parallel runways during IMC, particularly where various constraints prevent ILS installation, and will allow continued operation using SATNAV as a backup approach option if the ILS is out of service.
Task Force: Implement CSPO: SATNAV or ILS (37a)
Amend Independent Runway Separation Standards in Order 7110.65 (Including Blunder Model Analysis)
This increment amends runway spacing standards to achieve increased access to parallel runways with centerline spacing less than 4,300 feet without high-update surveillance, and implements this change at approved locations. Current runway spacing standards for independent closely spaced parallel approaches are based, in part, on outdated assumptions about aircraft blunder rates that include severity and frequency. Due to the fact that the blunder assumptions were based on information available 20 years ago and some subjective views at the time, current spacing standards may be unnecessarily conservative, limiting capacity and airport growth. This increment includes the collection and analysis of data leading to a revision of these assumptions, followed by a safety analysis to determine possible new, reduced, safe minimum spacing for simultaneous independent approaches in IMC, as outlined in FAA Order 7110.65.
Changes to standards will result in increased access in a number of possible ways, including reducing spacing for new runway construction and allowing independent approach operations where currently only dependent, or single-runway, operations are authorized.
Task Force: Revise the Blunder Assumptions (13)
Enable Additional Approach Options for New Independent Runway Separation Standards
The analysis that provided the basis for the recommended simultaneous independent parallel instrument approach (SIPIA) runway separation standard addressed the use of ILS, LPV and GLS approach operations, for determining the limits of safe operation utilizing current National Airspace System (NAS) infrastructure with no high-update surveillance. This increment will enable use of additional GPS-based approach options with vertical guidance that may include Lateral Navigation/Vertical Navigation, RNP and RNP Authorization Required for use in performing SIPIAs to runways at reduced lateral runway separation (less than 4,300 feet). It is anticipated that these approach options will meet the same independent runway separation standard as determined in Order 7110.65. However, further analysis is required to determine the supported lateral runway spacing. These additional approach options will allow for continued use of higher throughput procedures, for example, if the ILS is out of service or where no ILS currently exists.
Amend Dependent Runway Separation Standards in Order 7110.65
This increment will support the safety analysis and additional work required to identify a revised separation standard for simultaneous dependent parallel instrument approaches (runways spaced between 2,500 feet and 4,299 feet), as well as revise FAA Order 7110.65 to permit this operation. This would lead to a significant increase in the arrival rate for dependent operations.
Traffic Management Coordinators (TMC) establish initial traffic management planning and anticipated flow rates using arrival/departure rates and current/anticipated airport conditions. TMC functionality is distributed throughout the NAS to traffic management units at Air Route Traffic Control Centers, high-activity Terminal Radar Approach Control (TRACON) facilities, and at the highest-activity airport traffic control towers. Each plays a role in arrival and departure sequencing, depending upon the current conditions. The TRACON plays a major role in the spacing and sequencing in the terminal area. Arrival traffic is sequenced by using speed control and vectoring until cleared for the appropriate approach. Departures are handled in a similar manner with speed control and vectoring until transitioned to the en route environment. Additionally the Departure Spacing Program evaluates aircraft flight plans at participating airports, models projected aircraft demand at shared departure fixes, and provides windows of departure times to controllers based on projected fix crossing times.
In performing traffic synchronization functions, controllers receive input from various sources such as, voice and data communications, and weather and automation systems. Voice inputs include Pilot Reports via radio from aircraft, coordination air traffic control towers, other TRACON positions, adjacent ATC facilities, Traffic Management Unit, and the TRACON area supervisor.
Data inputs include track and weather data from Airport Surveillance Radar and Air Traffic Control Beacon Interrogator - Model 5/Mode S, and intent/flight plan data from the Host Computer System. The controller may also enter information directly.
Task Force: Runway Access
CRDA is an automation aid used by air traffic controllers to judge spatial relationships between aircraft that are destined for converging or intersecting runways. CRDA projects position information for an aircraft approaching one runway onto the straight-in final approach course of another aircraft approaching a converging or intersecting runway (known as "ghost" targets), thus allowing a controller to easily visualize and direct a safe and efficient separation distance between the two arriving aircraft. This activity is assessing the current use of CRDA functionality and facilitating the development of procedures to extend its use. This activity supports the implementation of an arrival/departure window tool at selected sites.
Task Force: Increase Capacity and Throughput for Converging and Intersecting Runways (9)