F063-B-011 Potential Procedures to Reduce Departure Noise at Madrid Barajas Airport William J. Swedish Frank A. Amodeo 7 January 2001 The contents of this material reflect the views of the authors, and do not necessarily reflect the opinions of Aeropuertos Españoles y Navegación Aérea (Aena), the U.S. Federal Aviation Administration, or any other party.
2 Proposed Runway Configuration 0 Predominant flow is northbound New Runways N
3 0 Southbound departures today can turn and avoid noisesensitive areas (red and orange) 0 Parallel departures would need to fly closer to these areas N (not to scale)
Independent Parallel Departures Standard ICAO/FAA Departure Procedures 4 0 Departure tracks must diverge by 15 immediately after takeoff - One track straight or turns away (implied) 760 m (2500 ft)
5 Southbound Departures 0 Greatest noise impact would be due to southbound departures at night (2300-0700 local time), - Noise Impact is population exposed to critical noise levels = 65 dba in daytime = 55 dba at night 0 Recommendation: To reduce noise impact for these departures, use only one runway - New Runway 15L, farther away from sensitive areas - Single departure track over open land - Less capacity, but demand is light
6 Alternative Procedures for Parallel Departures 0 As traffic grows, single runway may not provide enough departure capacity at night 0 Varying the departure flight paths may reduce noise impact compared to standard procedures - Reduce divergence angle to avoid populated areas, or - Turn both in same direction 0 Feasibility of such techniques at Barajas is not assured
Reduce Divergence Angle for Independent Departures 7 0 ICAO standard procedure: 15 divergence 0 10 divergence - Implemented at Toronto, Canada (3300 m runway spacing) - Investigating 5 divergence 0 Parallel departures for 5 NM - Implemented at Paris Charles de Gaulle (3000 m runway spacing) - Requires positive course guidance (e.g., VOR on runway centerline)
Toronto Pearson International Airport 3300 m (10,800 ft) Runway Spacing 8 0 Even at 5 divergence, there would be more separation between adjacent aircraft than ICAO standard case (15 divergence and 760 m) until >6 NM from runway end - 10 departure divergence ==> 15 NM Toronto 5 4265 m (14000 ft) 3290 m (10800 ft) 15 3245 m (10640 ft) 3750 m (12300 ft) 760 m (2500 ft) ICAO 5 NM 6 NM
9 Turn Both Departures in Same Direction 0 Concept: Independent departures with same-direction turns - New procedure, not explicitly covered by ICAO PANS = Would require more analysis, much testing - Need to ensure separation between departures = Minimum straight segment required on outside runway = Protects against a slow climb to 400 ft before turn from inside runway ~ 2 NM
Turn Both Departures in Same Direction (continued) 10 0 Independent departures with same-direction turns - New procedure with safety issues - Straight segment before turn takes aircraft closer to noisesensitive area = Will increase noise impact compared to turn at runway end 0 Alternative concept: Dependent departures with same-direction turns - Interval (e.g., 60 sec) between departures on different runways = Provides longitudinal separation - Departure capacity is function of this interval
Dependent Departures with Same-Direction Turns 11 0 Advantages - Turns are not simultaneous (side-by-side) = Straight segment not required - Procedure can be implemented gradually = Start with 60 sec inter-runway separation (for radar separation), reduce as pilots and controllers gain experience and confidence 0 Some safety questions - How close could the aircraft be? - What if one aircraft goes straight ( blunders )?
12 Preliminary Monte Carlo Simulation 0 Used simple dynamic model to calculate the Closest Point of Approach (CPA) 0 Departures from Runways 15L/R - Turn Angles from 15R: 5, 10, 15 - Divergence: 0 (parallel), 5, 10, 15 - Also blunders (15L departure does not turn) 0 Variable parameters - Takeoff Speed - Heading after Turn - Start of Turn
Mean and Minimum CPAs 5 Turn 30 sec. inter-runway departure 15R separation 5 Degree Turn 13 16000 14000 Mean CPA 12000 Distance (feet) 10000 8000 6000 Diverging Diverging turns turns are are still still required, required, to to increase increase minimum minimum CPA CPA Mean 15R #1 Mean 15R #2 Min 15R#1 Min 15R #2 4000 2000 0 Minimum CPA 0-5 -10-15 -20 Other Turn Angle
Conclusions 14 0 High noise impact for southbound night departures (2% of year) can be greatly reduced by using only a single runway for departures 0 Reducing departure divergence, if feasible at Barajas, could potentially reduce noise impact and/or provide additional departure capacity 0 Dependent departure / same direction turn procedure appears promising, but further analysis is needed - Especially blunder performance