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REAL-TIME INTER-MODAL SUBSTITUTION (RTIMS) AS AN AIRPORT CONGESTION MANAGEMENT STRATEGY. Mark Hansen Yu Zhang University of California Berkeley. Outline. Diagnosis Concentration of Delays Capacity Profiles Cure CDM Inter-modal substitution Ground-transport-enabled diversion
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REAL-TIME INTER-MODAL SUBSTITUTION (RTIMS) AS AN AIRPORT CONGESTION MANAGEMENT STRATEGY Mark Hansen Yu Zhang University of California Berkeley
Outline • Diagnosis • Concentration of Delays • Capacity Profiles • Cure • CDM • Inter-modal substitution • Ground-transport-enabled diversion • Public policy role
Concentration of Delays • Spatially • Causally • Temporally • Passenger Impact
Concentration of Delays in Time, 2007 to Date >80% of delays on worst 20% of days
Statistics—Yearly Delayed Passenger From Evans and Clarke 2002 pp82
Introduction —Delay in NAS • Disrupted passengers are only three percent of the total passengers, they suffered 39 percent of the total passenger delay. From Barnhart et al. 2004
Air Traffic Flow Management (ATM) • Ground Delay Programs (GDP) • Ration-by-Schedule (RBS) • Compression • Collaborative Decision Making (CDM) • Flight Schedule Monitor (FSM) • Ration-by-Schedule (RBS) • Compression • Slot Credit Substitution (SCS)
Procedure of Collaborative Decision Making (CDM) ATCSCC, Facilities and AOCs Evaluate Demand vs. Capacity AOC Smart Cancellation Problem Proposed GDP Advisory AOC Response (Cancellations) Is the GDP still required? Yes AOC Response (Re-ordering and Cancellations) Compression Issue GDP (RBS) No Exit loop when program expires or is cancelled End Slot Credit Substitution Based on Metron 2004
Ideas • Substitute short-haul flights with surface transport when capacity temporarily drops at hub airports • Divert flights to alternate airports and provide surface transport between alternate and original airports.
Hub-and-Spoke Network Bottleneck: hub airport with capacity constraints
Inter-modal Substitution of Short-haul Flights Transport time on fast link and delay due to node capacity Slow link Fast link Transport time on slow link
Inter-model Substitution plus Diversion Transport time on fast link and delay due to node capacity Slow link Fast link Transport time on slow link
Why Focus on Short-haul Flights? • Provide airlines more flexibility to make smart tactical cancellations • More capacity for large-jet operations • allow cancellation decisions to be made with more reliable capacity information. • Reduce miss connections and passenger delay • Canceling short-haul flights inconveniences fewer customers • Passengers save time if the extra transportation time with surface modes is less than the flight delay they would encounter.
Numerical Example ― Input Airport: San Francisco International Airport (SFO) Schedule: a typical Thursday in 2004 Source: the Official Airline Guide (OAG) Airline: a hypothetical feeder airline (Airline S) serving all segments less than 500 miles. Detail: 130 flights from 6:00am to 12:00am (18 hours). Capacity: severe capacity shortfall starting from 6:00am and ending at 10:00am. two arrivals per hour in the shortfall period and eight arrivals per hour afterwards.
Scheduled and Hypothetical Cumulative Arrivals without Cancellation
Numerical Example ― Programming and Solution See more results
Combined Concept Inter-modal substitution Diversion Operate as usual
Public Policy Role • Individual airlines unlikely to implement these ideas on their own • Policy interventions • Push airlines to reduce operations in periods or reduced capacity (pricing) • Assist airlines in developing systems for surface transport to enable real-time substitution and diversion