page 1page 2page 3page 4page 5page 6page 7page 8page 9page 10page 11page 12page 13page 14page 15page 16page 17page 18page 19page 20page 21page 22page 23TERMINAL PARKING LOT EXPANSION AT THE DALLAS-FT. WORTH AIRPORTforDr.Dick BarrOREM 4390byRichard W. HansenwMay 8,, 1982American Airlines Terminal Parking Expansion.The American Airlines division at the Dallas Ft.Worth regional airport is in need of a program to system-atically expand the terminal parking facilities. TheNorth Texas Commision is the agency which is concernedwith the planning and developement of the nev facilitiesat DFW, as they are needed. At present stage the airportis only fractionally completed. The problem with whichthis paper is concerned is that of finding a good approachto developing additional terminal parking spaces for the2e and 3e terminal parking facilities at the AmericanAirlines facility.At the current time the 2e parking lots have a totalof1'577parking spaces, while the 3e lots have2943.These parking lots have enough capacity to handle thefull parking load at this time, but they will. need tobe added onto sometime in the not too distant future.In addition to these parking .lots there are plenty ofremote parking facilities. People generally prefer touse the near by terminal parking however. Setting asidethe convenience factor, the growth rate at the airportwill call for these additional parking places anyway.What the problem calls for here is to determine thetimes at which the additional terminal parking lots willbe needed and to determine which order the new parkingadditions should be added in.As shown on the map of the airport, the terminalsare each surrounded by three stuctured parking lotslabeled with subscripts a., b and c. There is also afourth lot in each terminal which is labeled with a d.American has the option to use all or part of both ofthe terminals 2e and 3e as they grow in the future.At the present time, American is using terminal 3e atabout 6n/ capacity and rents out part of terminal 2e.There is half of terminal 2e that is still under con-struction at this time. It is feasible that Americancould almost double their scale of operations within thefive year period of my study.To obtain the data needed for this study I wasaided by the people at the North Texas Commision. Thedata was easy to obtain for the most part as'they areworking on the same problem at this time. The firstthing needed was a tentative flight schedule. A man bythe name of Johnny Mcknight, a project architect at DFW.,informed me that American had a. growth rate of about 10%per year at DFW., but that next year they predicted itwould be a little higher, almost 18%. TheAmerican AirlinesTentative flight Scheduleis enclosed in the model of thisna.per. Ulhen doing my-model I went back in time a few yearsto see how my results were comparing to the results andfigures which have already been established. By using theflight schedule from February, 1082 I was able to estab-lish the ratio of usage for the different types of ai-r-cra.f.t. I adjusted the ratios slightly because I was toldthat American was going to start replacing the use of 6 oftheir 727's by one 747 and by five DC10's. Also of im-portance is the ratio of total seats per plane (filled)to the total number of seats available (filled + empty).American's seat filling ratio is about F0%. The numberof people from Dallas or Ft. Worth over the total numberTof people on board comes out to be about 40%. From hereal- we need is the capacity of each type of airplane andH,4.we can come up with the results which I_ontheComputations Table for the Figures of the Number ofPeople from DFW.These people are the only potential usersof the terminal. parking lots. We also found out that 20%of the passengers from Dallas or Ft. Worth do actuallyuse the terminal parking lots The last main data prob-lem leftwasthat of finding out how long those peopleleft their cars at the airport. The maximum usage of theparking lot came in the middle of the week because mostof the travel was business travel, and most of the:peoplewere back from their business trips by the weekend.This pattern basically repeats from week to week, withthe business people leaving on monday or tuesday andreturning home on thursday or friday. By talking to theworkers at the ticket gates and from traffic planners,Ifound out that of the people using the terminal park-ing Tots, about 80% of them stayed for 3 days and theremaining 20/ stayed for one day. The number of peoplewho used the terminal parking for long periods of timewere fairly few as the rates for terminal parking aretwice as high as those for remote parking. Very few peo-ple ever left their cars in the terminal lots for overa week. From all of this information I was able to'comeun with a set of figures for theMaximum Number of Park-ing-places Neededat the terminal parking facilities ofterminals 2e and 3e.1.Wilbur Smith and Associates3ThE PIPAUDI14011-The ModelThis model is basically set ur to minimize thecurrent costs assccf ted with the terminal Perking lotexpansion problem. The costs which I used were,1200.00tper space for the spaces on grade, and 12,000.00 dollarsper space for the spaces on structure. I assigned weightso the hundreths digit place insomeof the values fordifferent parking lots. The larger the weight value,the later the parking lot would he constructed. Theseweighted values were set up accord i noo to the priori ti e•-sof the North Texas Commi si on for oournno„es of having thelots nearest the terminals cornstructed fir,-,t for pass-enger convenience and to minimize the distances whichcustomers would have to walk. The objective functionis simply to minimize the costs associated with hui1d-ing. Al though the final costwoo-10be the same no mat-ter which order thepark.i.nglots were rna it t, the greatercosts in this model would be incurred at the letestposgi_ble dates, in such a way to maximize customerrconvenience. The actual cost error which is caused byadding in the weighting factors -is only about ?1'133.00which can be considered fairly net lig, bl e whenlookingat the total constuction costs.The first 12 constraints are used to state themaximum number of parking places available in theircorresponding parking 7,bts.=-Constraint number 13isaless than or equal to constraintstatingthat the totalnumber of parking spaces in the 3F1-lower level lots donot exceed the 2E parking spaces by a difference of morethan 700 spaces total . This wasdorhFcaus e