Airfield Capacity Airfield capacity is typically described in terms of hourly capacity and annual capacity under good and poor weather conditions. Table A-1 below reflects the hourly capacity for MSP in optimum, marginal and poor weather conditions. MSP’s current airfield capacity is about 141 aircraft operations in optimum conditions and 114 operations in poor weather, when instrument flight rules are being used due to low-level, heavy cloud cover and/or low visibility. Since 2015 when new Converging Runway Operations (CRO) measures were put in place, the Federal Aviation Administration (FAA) has worked to refine the procedures at MSP to regain capacity and reduce environmental impacts as much as feasible. A CRO exists when runways that do not physically intersect have flight paths that could intersect within one mile of the runway ends. At MSP, the extended centerline of Runway 35 intersects within one mile with the extended centerlines of both Runway 30L and 30R. Since arrivals on Runway 35 are only from the south, potential convergence in flight paths only would occur if an aircraft executes an aborted landing (go-around) on Runway 35. CRO procedures at MSP prevent an aircraft that aborts its landing on Runway 35 from conflicting with aircraft departing from Runways 30L or 30R, as shown in Figure A-1. The new CRO rules caused a change in runway use trends and slowed arrival rates down from the 90 arrivals per hour during north flow at MSP. Throughout 2016 and 2017, the MSP Noise Oversight Committee (NOC), MAC board, surrounding city councils and neighborhood groups received regular updates from the FAA on its efforts related to the new CRO. In September 2016, the NOC unanimously passed a resolution requesting the FAA evaluate the current and future environmental and capacity impacts from the new CRO rules and to communicate the findings back to the NOC. The MAC board of commissioners took unanimous action supporting the NOC resolution and forwarded it to the FAA. During 2017, the FAA made substantial progress in designing and employing technological tools within its air traffic control system to revert changes in runway use, regain some capacity loss, and reduce air traffic controller work load at MSP during CRO. In January 2017, the FAA began using two Arrival Departure Windows (ADWs) for each of the parallel runways. In order to use two ADWs at the same time, a thorough risk assessment and approval process was required. These windows help alternate flights departing Runways 30L and 30R with flights arriving to Runway 35. Use of the two ADWs increased MSP’s northerly arrival rate from 64 to 75 aircraft per hour. Further, in June 2017, the FAA implemented a Converging Runway Display Aid (CRDA) which aligns aircraft arriving to Runways 30L with 35 to offer efficiency gains in sequencing departures to the northwest. The CRDA tool helps arrivals on Runway 35 line up with arrivals on Runway 30L to create a predictable departure gap for Runway 30L. This has allowed the FAA to flex arrival rates up to 84 aircraft per hour during three peak arrival demand periods throughout the day, reducing arrival delays. Similarly, in August 2017 the FAA began flexing departure rates up during periods of peak departure demand by routing Runway 35 arrivals to either parallel runway (30L or 30R), thus eliminating the dependency on ADWs for aircraft departing to the northwest. The FAA’s implementation of this suite of tools has largely reverted runway use trends to pre- CRO conditions. While the FAA’s efforts related to CRO were taking place, the MAC was in the process of updating the Long Term Comprehensive Plan (LTCP) for MSP. The LTCP is a forward-looking document that acts as a roadmap for possible facility improvements needed for the next 20 years to meet deficiencies identified through the process. A component of the LTCP document is a 20-year forecast noise contour to provide an estimated depiction of the future noise impacts at the airport. At the request of elected officials and community members, and as recommended by the NOC, the MAC deferred its LTCP efforts to ensure the FAA’s CRO efforts and any resulting changes to ground and air operations are taken into account in the MAC’s long term planning efforts. The MAC plans to initiate the MSP LTCP update in 2018 and complete the document in 2020. Figure A1: CRO Rules protect Circled Area of Convergence at MSP MSP Airfield Capacity Table A-1 Weather Conditions Operations per hour Optimal Rate (1)............................................ 141 Marginal Rate (2)........................................... 126 IFT Rate (3).................................................... 114 Notes: (1) Ceiling and visibility above minima for visual approaches. (2) Below visual approach minima but better than instrument conditions. (3) Instrument conditions (cloud ceiling less than 1,000 feet or visibility less than 3 miles). Source: Federal Aviation Administration Air Traffic Control Tower Analysis vi vii