Implications of Automated People Movers for Airport Terminal Configurations

Transcription

1 Implications of Automated People Movers for Airport BY L DAVID SHEN A ccording to the Federal Aviation Administration (FAA), 800 million people are expected to board airplanes in In 1987, the 17 largest airports accounted for more than half of the air passenger enplanement in the United States. As airports get larger and more complex, passengers expect more help from curbside to aircraft seat. With extensive hotel, shopping, and recreational complexes spread across thousands of acres, many major airports not only serve cities, but are becoming cities in themselves. Just as in cities, the biggest challenge in large airports is how to move people on the ground. An innovative Automated People Mover (APM) system recently has become a popular way to meet this challenge. With an APM, new airport terminal configurations and existing terminal modifications that were impossible 0 years ago have become regular. Tampa International Airport was the first airport in the United States to incorporate an APM into its terminal design. Year after year, domestic and international travelers responded to the change by voting it as America s most popular airport facility. Conversion Factors To convert from to multiply by ft m mi m 1609 As more major airports follow Tampa s lead, it is clear that future airport terminal configurations will be substantially different than they were 0 years ago. Given this change, the purpose of this article is to discuss the impact of this unique system on terminal configurations at major airports. APM Systems at Airports The APM system is an automated, electric-powered, driverless vehicle operating singly or in multi-car trains on steel or concrete guideways. It can carry from,000 to 0,()()0 passengers per hour with headways as short as 60 seconds, offering convenience comparable to modern elevators. Ride quality is among the best of any transit system in the world. APM vehicles travel at speeds up to 35 mph, but accelerate and decelerate smoothly and swiftly. The vehicles stop and start automatically, and they can operate in an on-demand mode during off-peak hours to minimize energy consumption. The vehicle is about the size of an urban transit bus. Because the duration of most rides is short, vehicles in most airport systems have been designed to carry standing passengers; few seats are provided. Guideways for the vehicles can be constructed above ground, at grade, or underground (grades can run as steep as 10 percent). The bidirectional capability of the vehicles allows the designer more flexibilityy in route layout, The simplest layout is a single guideway in which the vehicles shuttle back and forth between two points. This design is defined as a shuttle. Adding a guideway parallel to the first permits counterflow, so two trains can move in opposite directions at the same time. A loop can be constructed to serve several locations. When site limitations prevent loop construction, a pinched loop, with a switch at each end of parallel shuttles, provides benefits similar to a standard loop design. z The basic characteristics of existing airport APM systems are shown in Table 1. The average capital cost per singletrack mile of APM construction in 1980 dollars for the eight existing airport APMs in the United States was about $0 million. The cost varies from airport to airport depending on site features and the systems used. At present, only five of the top 0 airports (Atlanta, Dallas, Miami, Houston, Orlando) in the United States have operational APM systems in their terminals. As for the remaining 15 major airports, four APMs are under construction at Chicago, Pittsburgh, Newark, and Denver; and five arc being proposed or studied for San Francisco, New York s LaGuardia, Boston, St. Louis, and Washington National. Before APM Before the introduction of the APM system at Tampa airport in 1971, seven airport terminal configurations, each with 4. ITE JOURNAL. FEBRUARY 199

2 varying degrees of centralization, were commonly used. These terminal configurations are described below. Linear This arrangement gives a small length of airside interface in relation to the size of the terminal. It is frequently used for low-volume airports where the number of gates required would not necessitate an inconveniently long terminal. Pier This system is found at most airports. With a central passenger processing facility (terminal block), this arrangement may not have sufficient perimeter to accommodate the required number of aircraft gate positions. Therefore, piers are added to the building to increase the perimeter without substantially increasing the total floor area. This design provides large passenger-processing capacity without excessive land requirements and is economical to build; however, passengers typically must walk for excessive distances. Wirasinghe and others. have shown that the mean walking distance for all passengers in terminals with piers of equal length can be minimized by choosing an odd number of piers closest to,*1, /> where G = number of identical gates, SC,= spacing between gates on one side of a pier, and S,, = spacing between fingers. T (Quasi-Linear) A T-shaped terminal is a combination of a linear terminal and two piers that extend along the face of the terminal block. High efficiency in terms of wdlking distances is obtained by using both sides of the piers for gates. Wirasinghe and Vandebona< have shown that the T-terminal is superior to other moderatesized configurations, such as single pier, dual pier, and rectangular. Satellite A conventional satellite terminal has a central passenger processing facility that is linked to one or more satellites usually by underground connectors. Aircraft gates are arranged on all sides of each satellite, which can be rectangular, circular, and T-shaped. Satellites allow Table 1. Existing Airport APM Systems Airport Tampa, Florida Seattle, Washington Dallas, Texas Atlanta, Georgia Miami, Florida Houston, Texas Orlando, Florida Las Vegas, Nevada Gatwick, London Birmingham, U.K. Changi, Singapore more gate positions than would normally be accommodated by an airport without significant changes in the terminal block. Pier Satellite This is a modification of the basic pier and satellite concepts. Aircraft are parked around a rotunda at the end and along the side of the finger. This design facilitates passenger assembly and ticketing activities at the aircraft gates. However, this design also creates excessive wdiking distances. Unit Terminal This design uses two or more separate, self-contained buildings. Each houses a single airline or group of airlines, and each has direct access to ground transportation. This design usually is justified at high-volume airports where a pier or satellite design would create excessive walking distances. However, it can create serious problems for passengers interlining from one airline to another and should therefore not be used in airports with significant numbers of such passengers. Transporter This design uses mobile conveyance systems similar to buses or mobile lounges to take passengers to and from aircraft. Although it can significantly reduce walking distance, it also can increase passenger processing time and create a traffic-conflict problem on the aprons. In addition, a large fleet of transporters is relatively expensive to operate and maintain. Configuration Summary Given a terminal of a certain size (that is, the number of gates is given), it is APM System Length 4 double shuffles, 1,000 ft. each loops/1 shuffle, 8,900 ft. all 4 loops, 13 miles all 1 pinched loop, 1 mile 1 double shuffle, 1,300 ft. 1 pinched loop, 7,500 ft. 3 double shuffle, 1,900 ft. each 1 double shuffle, 1,00 ft. 1 double shuffle, 0,4 miles 1 double shuffle, 0,4 miles double shuffles, 0,8 miles Number of Stations possible to choose a design that will minimize the walking distance for a specified configuration. However, if that minimum is still unacceptable, other terminal configurations or unit terminal systems should be considered. Many of the configurations described above can be improved by using relatively low-cost moving-sidewalk systems. However, at very large airports, which generally have several terminals or satellites and high transfer and interlining traffic, an APM system might be the best way to manage passenger traffic. It is not uncommon for an airport to use more than one design configuration in its passenger terminal layout in order to reduce passenger walking distance. Most airport designers agree that 600 feet is an ideal terminal walking distance maximum and admit that any distance greater than 1,00 or 1,300 feet must be considered unacceptable. However, as air passenger traffic grew, the required expansion in terminals conflicted with the designers standards. The consequent actions of airport authorities supported the development of new terminal configurations and the analysis of various transportation systems. APMs have become an important component in many airport expansion plans. Changes in Travel Patierns Although the latest data on transfer passengers is incomplete, it can be safely assumed that the radiating (hub-andspoke) route patterns that airlines have used more and more since deregulation have contributed to the increase in the number of transfer passengers at major airports. The percentage of transfer pas- ITE JOURNAL. FEBRUARY 199.5

3 sengers at selected major airports in the United States before airline dercgukrtion is shown in Table, The hub-ancf-spoke system is a mixed blessing for air passengers: it widens travel options but leads to schccfuling problcrns. While more people are flying than ever befbrc, only a few get to go straight from point A to point B. Dallas-Fort Worth (DFW) international Airport is a good example of how unforeseen events can render a major :iirport design outmoded. DFW was designed for the convenience of local passengers, those living in the Dallas-Fort Worth area who begin and end their trips at DFW. When DFW was designed, more than two-thirds of the traffic at Dallas Love Field (the old Dallas Airport) were passengers departing from Dallas and returning to Dallas. Then came deregulation, intense competition among airlines, and the advent of hubbing. As a result, the percentage of interline transfer passengers at DFW jumped from one-third to two-thirds of all passengers. Recent records show that half or more of the traffic at major hubs such as Atlanta, Chicago, Denver, and St. Louis neither originates nor terminates in these cities. This means that there is a large number of interlining passengers and, as a result, more terminal traffic. It is criticiil to provide a transportation system that can effectively handle the flow of traffic and reduce walking distances for all passengers. with APM The APM system can be built into any existing airport terminal design at the time of airport expansion or modification. This is what happened during modification in Seattle, Miami, Houston, and Las Vegas as they generally involved the construction of one or more new remote satellites; the APM systcm connects the satellite(s) with the main terminal. In Seattle and Houston, all of the airport facilities are connected by the APM; in Miami and Las Vegas, only the new remote satellites are connected to the main terminal by APM. New airport terminal configurations with APM systems generally fwor centralized operation because it utilizes airport resources more efficiently. Remote satellites (RS) and remote piers (RP) are the two most popular designs. DFW, which is basically an old decentralized operation unit terminal design conceptualized in the late 1960s, is the only exception, These three terminal configurations with APMs, shown in Figure 1, arc defined below. Remote Satellites This design has a central termin:il and several remote satellites connected by an APM shuttle train either above or below the apron, The design usually takes full advantage of the APM system by kxating all ticket purchase, baggage check and reclaim Facilities, and other main passenger services in the main terminal area. Only the holding lounges and supplementary check-in facilities for passengers not carrying baggage arc located in the satellites. Tampa and Orlando international airports are examples of remote satellites design. The cfcsign is simple and userfricmdly, especially for first-time passengers. It also is extremely flexible in that it can bc expanded with little difficulty and generally creates short walking distances. However, for very high-volume airports (annual passengers more than 40 million), this design inefficiently uses land, because it spreads out across a great distance. However, since only the top four airports in the world now have this kind of heavy passenger volume, the remote satellites design should be popular at major airports in the future. Table. Transfer Passengers in the U.S. Betore and Atter Deregulation Before Deregulation After Deregulation Total 1976 Total 1989 Passengers Percentage Passengers Percentage Airport (millions] Transfer (millions] Transfer Chicago Dallas-Fort Worth Los Angeles Atlanta New York Kennedy San Francisco Denver Miami n/a Table 3. Evaluation of Terminal Designs with APM Systems 59, ,9 43,3 30, ,6 3,4 Level of Economy Flexibility for Security Terminal Design Service of Design Modifications Control Remote Satellites Excellent Good Very Good Excellent Remote Piers Excellent Very Good Very Good Excellent Unit Terminal Good Poor Good Poor Table 4. Typical Walking Distances at Existing Airports with APM Systems Originating Passengers Interlining Passengers Typical Minimum Maximum Maximum Terminal No. of Walking Walking Walking Design Gates Dktances Distances Distances Remote Satellites Remote Piers ,300,000 Unit Terminal ,00 6. ITE JOURNAL. FEBRUARY 199

4 Remote Piers This is a new design based completely on the effectiveness of APM. The remote piers (concourses) are linked with the central terminal via APM under the apron. The terminal complex is located in the middle of the airfield between the system of parallel runways. This facilitates the movement of aircraft between gates and runways, makes for short taxiing time, and alleviates congestion. This design uses land efficiently, as shown by Atlanta, one of the heaviest traffic airports in the world, which was built in an area of less than 3,800 acres. Parallel alignment of the concourses ensures the efficient use of apron space. One thousand feet of apron separates the twin parallel piers so that two widebody jets can simultaneously taxi between them while two other widebody planes are parked at their gates. This design is ideal for high-volume airports, especially those with a significant number of domestic transfer and interlining passengers. The proposed new Denver International Airport will incorporate this design. One major problem of this design is that a long pier creates longer-than-desirable walking distances for transferring passengers. This also is true for Atlanta, where the maximum walking distance for interlining passengers,,000 feet, is the same as the length of one concourse. This problem can be overcome by designing the facility with greater numbers of shorter piers. Optimal, total cost-minimizing geometries for remote pier terminals with a central APM system are under investigation. Preliminary findings indicate that a small number of piers of different lengths are suitable. 4Surface + * Access Terminal + APM L=OP the layout is too complex for first-time users. No new airport has used this design since DFW opened in Table 3 shows an evaluation of the terminal configurations with APM systems. It is clear that APM eliminates the tiring terminal trek from parked car or arriving plane to the gate. At airport terminals designed with APM systems, the maximum walking distances generally are less than 1,300 feet. This is acceptable to most airport authorities. Table 4 shows the typical ranges of walking distances at airports designed with APM systems. In addition to the other benefits offered by remote piers and satellite designs using APMs, the trend toward increasing airport security for passenger and luggage processing also favors these designs. Two new APM systems are under construction at Chicago O Hare and Pittsburgh airports. The system layout at O Hare resembles a remote piers design; the system at Pittsburgh resembles remote satellites design. Summary and Conclusions Walking distances in airports can be reduced through appropriate geometry and moving sidewalks. This article demonstrates that the following points must. rface cess Unit Terminal This decentralized design is the same as the early unit terminal design without APMs. The only difference is that the APM system is built into the terminal design to connect different unit buildings, providing a high level of interline ground connection service. DFW is an example of this design. However, this design does not use land efficiently and requires an extraordinary number of APM guideways to make it work at Dallas. Some connecting passengers must walk in excess of a mile between gates. In addition, there is no focal point for transfer passengers, and, (b) Remote Piers,Urf.ce+i!i?!!km i???!!i,,e<f-w-+q=w-- (c) Unit Terminal Figure 1. Airport terminal configurations with APM systems. ITE JOURNAL. FEBRUARY 199.7

5 be considered in airport design assessments: For large airports, APM systems reduce terminal traffic congestion. Remote satellites design with APMs is acceptable when the percentage of transfer passengers is low and land availability is not a problem. Remote piers design with APMs is found to be better when the percentage of transfer passengers is high and land availability y is a problem. It is likely that APM systems at maior airports will become ~tandard. References 1. Shen, L.D. Automated People Mover s Impact on Airport Circulation, /TE 1989 Compendium of Technical Papers. Washington, D. C.: Institute of Transportation Engineers, 1989: Westinghouse Transportation Systems and Support Division. Aufomafed Transit Sysfem Guideway Planning Guide. Pitts burgh, PA: Westinghouse Electric Corporation, Sprtmle, W.J. Airport Automated People Mover Systems. ITE 1989 Compete - dium of Technical Papers, Washington, D. C.: Institute of Transportation Engineers, 1989: AEG Westinghouse Transportation Systems, Inc. Westinghouse AGT Systems Installed. Pittsburgh, PA: Westinghouse Electric Corporation, Wirasinghe, SC., S. Bandara, and U. Vandebona. Airport Terminal Geometries for Minimum Walking Distances. In Gantre, N.H. and N. H.M. Wilson eds. Transportation and Traffic Theory. New York: Elescveir, 1987, pp , Wirasinghe, S, C., and U. Vandebona. Passenger Walking Distance Distribution in Single and Dual Concourse Centralized Airport Terminals. Transportation Research Record No, Wirasinghc, SC., S. Bandara, and F. Lee, Airport Terminal Planning: Gate Positions and Configurations. Research Report CE 85-16, Department of Civil Engineering, University of Calgary, Calgary, Canada, Transportation Rcasearch Board, Future Development of the U, S. Airport Network, National Research Council, Leigh Fisher Associates, Inc. Airline Airport 7rminal Desigtz Possibilities. San Francisco, CA: October lo. Shen, L.D. Airport Terminal Designs wit h Automated People Movers. Trans - poria(ion Research Record No. 173: 1990, 30-9, DE Lon-Li David Shen is an as.vociate professor and chairperson with the Department of Civil and Environmental En,gineer. - ing at Florida International University, the State University of Florida at Miami. He received his M. S. and Ph.D. from Clemson University. Shen is a registered professional engineer in California, Maryland, and Florida. ~? bookstore The 1990 Clean Ah Ad and the Transpe#on Prepared fbt- an ITE Education Foundation seminar. this notebook provides timely information on the 1990 Clean Air Act and how it will affect the transportation engineering profession. Provides overview and legislative history of Clean Air Act amendments and information on conformity requirements. Discusses how to integrate air quality planning with the metropolitan transportation planning process, and describes how the California Clean Air Act of 1988 impacted transportation decisionmaking. ITE, Spiralbound. Publ. No. PD-018. $75 ($50/ITE members). Transporlaiion and Land Development BY V.G. STOVER F. KOEPKE AND An invaluable source of information that will prove useful in desi~ning traffic access, circtdatmn, and parking systems for new or redesigned developments. Covers transportation and urban development, site planning, traffic analysis, functional circulation systems, intersection design, access and site circulation design, parking and service facilities, and drive-in facilities. ITE/Prentice-Hall, pp., casebound. Publ. No. TB-0f)7. $56. Add 10% shipping and handling to your order., # Please send me _ copies of Trans@rtatiort and Land Dedoprnznt. Please send me _ copies of The 1990 Clean Air Ad and ttw Transjmt-tati(rnEn,qiruwring Professtim. Check for $ enclosed. Charge my Visa Mastercard Acct. ><). hi>. 1),,1, N.,,,,, Sigmtum Ship N<Ime to: (.omp<myltim,.kdd!,5, (:IIF l]mt<il (,odcl(k.ntr. 0.>1 ime I dcphorw Sl,,tt Scncf order form with payment to: ITE Bookstore 55 School St., S.W., Suite 410 Washington, DC Tel.: 0/ Fax: 0/ J 8. ITE JOURNAL ofebruary 199