1 REAL-TIME INTER-MODAL SUBSTITUTION (RTIMS) AS AN AIRPORT CONGESTION MANAGEMENT STRATEGY Mark Hansen Yu Zhang University of California Berkeley

2 Outline Diagnosis –Concentration of Delays –Capacity Profiles Cure –CDM –Inter-modal substitution –Ground-transport-enabled diversion –Public policy role

3 Concentration of Delays Spatially Causally Temporally Passenger Impact

4 OPSNET Delay at SFO OAK SJC

5 Delays at SFO

6 Concentration of Delays in Time, 2007 to Date >80% of delays on worst 20% of days

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8 Statistics—Yearly Delayed Passenger No.AirportDelayed Passenger 1LaGuardia61,120 2 Chicago O ’ Hare 57,545 3Newark37,132 4Atlanta28,229 5San Francisco24,478 6Boston24,120 7Philadelphia21,521 8Dallas Fort-Worth20,638 9Los Angeles17,141 10Phoenix14,024 From Evans and Clarke 2002 pp82

9 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 PassengerAverage Delay% Passengers % Total passenger Delay Disrupted303 minutes3.20%39% Non- disrupted 16 minutes96.80%61%

10 Historical Capacity Scenarios at SFO

11 Historical Capacity Scenarios at OAK

12 Clustering of Joint Clusters at SFO and OAK

13 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)

14 Procedure of Collaborative Decision Making (CDM) ATCSCC, Facilities and AOCs Evaluate Demand vs. Capacity Proposed GDP Advisory Is the GDP still required? End AOC Response (Cancellations) No Yes Issue GDP (RBS) AOC Response (Re-ordering and Cancellations) Compression Exit loop when program expires or is cancelled AOC Smart Cancellation Problem Slot Credit Substitution Based on Metron 2004

15 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.

16 Hub-and-Spoke Network Bottleneck: hub airport with capacity constraints

17 Inter-modal Substitution of Short-haul Flights Fast link Slow link Transport time on slow link Transport time on fast link and delay due to node capacity

18 Inter-model Substitution plus Diversion Fast link Slow link Transport time on slow link Transport time on fast link and delay due to node capacity

19 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.

20 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.

21 Scheduled and Hypothetical Cumulative Arrivals without Cancellation

22 Numerical Example ― Programming and Solution w/o cancel Cancel w/ IMS Total cost ($) Cancellation25 Substitution22 See more results

23 Combined Concept Inter-modal substitution Diversion Operate as usual

24 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