Delays at Logan Airport Master of Global Management Michael Calo Ilyas Cagar Operations Management and Research Anne-Claire De Briey Professor Ocampo y Vilas Margaux Lonbois Laura Valkiers William Vermeulen
DelaysatLoganAirport
MasterofGlobalManagement MichaelCalo IlyasCagarOperationsManagementandResearch Anne-ClaireDeBrieyProfessorOcampoyVilas MargauxLonbois LauraValkiers
WilliamVermeulen
TheCurrentSituationatLoganAirport
Ourcaseanalysistakesanin-depthlookatthecausesandplausiblesolutionsforthedelays
experienced at Logan Airport in Boston, Massachusetts. The data used to analyze the delays fall
beforeanduntil theyear,2000.Theproblemswithin LoganAirport’sefficiencyarepredominantly
duetothehighdegreeofdelaysduringpeakperiodsthroughouteachday.In2000morethanonein
four flights were delayed, a total of 27% of the flights. As forecasted, Logan Airport expects the
passenger volume to rise in the upcoming years,making the search for a solution to the delays a
pressingconcernfortheorganization’slong-termefficiencyandsuccess
Oneprimarycause fordelaysare theadverseweatherconditions that frequentlyvisits the
NewEngland region.Boston’sharsh climateand severewintersmake theairport very sensitive to
weather fluctuations. In cases of adverse weather conditions, the amount of planes delayed
dramaticallyincreasesfrom5%to12%.Normaloperationsentailtheuseofthreerunways,butwith
adverseweatherconditionstheamountsofrunwaysinusecanbelimitedtotwooronedependent
ontheseverityoftheweatherconditions.Duringaverageinclementweather,arrivalanddeparture
operationsareusually limitedtotheuseoftworunways.Theuseofonlytworunwaysresults ina
dropintheamountofoperationsfromanormal118–126toamuchlower78–88operationsper
hour. Incomparisonto theaverage inclementweatherevent, severeweatherconditionsareoften
due to intensenorthwestwinds thatare frequentlyaccompaniedbyhigh levelsof snowfallduring
thewintermonths.Duringtheseconditions,operationsarelimitedtoonerunway,creatingmassive
delaysforpassengers.Operationsdroptolowerthan50%ofnormaloperationsatabout40to60per
hour.
Another source of the delays, originate from Logan Airport’s complex interactive queuing system.
ThefleetsthatoperateontherunwaysatLoganAirportconsistof3maincategoriesofaircrafts.The
largest planes at this airport are the Conventional Jets, which have an on-board capacity of 150
passengers.ThesecondaircraftthatusestherunwaysatLoganAirportaretheRegionalJets,witha
maximum capacity of 50 seats. The last and smallest aircraftmodel to utilize LoganAirport is the
Turboprop,whichareplanesthatcanholdupto19passengers.Theuseof threedifferentsizesof
aircraftson the same runwaysat LoganAirport is a sourceofmassivedelayson flight turnaround
time. This is primarily caused by the differing amounts of time and space needed for takeoff,
dependentonthesizeoftheaircraft.
As previously stated, Logan Airport forecasts that there will be influential increases in
passengersthatwillutilizetheairportinupcomingyears.Tocopewithandprofitfromthisincrease,
a solution must be found that solves or at least minimizes the delays. One of these proposed
solutionsistheconstructionofanadditionalrunwaythatwouldalleviatethedependencyonlimited
runwaysduring inclementweather conditions.Due to severalenvironmental andpolitical reasons,
numerous groups, with notable representation in the city, oppose the construction of the new
runwayandultimatelydoubtifthenewrunwaywouldbeaneffectivesolutiontothedelays.Another
solutionthathasbeenproposedistheuseofdemandmanagementthroughtheinstallmentofpeak-
period pricing. This strategy assists in determiningwhich aircrafts can operate on each runway at
givenpoints intimeand limitsthedelaysthatare influencedbythecomplexmixofdifferentsized
aircraftsutilizingthesamerunways.
Followingthisbrief introduction intothecurrentsituationatLoganAirport,wewillanalyze
theeffectofPeakPeriodPricingondelay costs, theeffectofPPPondifferentmixturesofaircraft
typesandontheirrevenuesandfinally,thearrivalandserviceratesandtheresultsfromarrivalrates
exceeding service rates. From the data collected, conclusions will be made and we will provide
recommendation pertaining to the use of Demand Management and/or the construction of an
additional runway to curtail the delays caused by a growing amount of passengers forecasted to
utilizeLoganAirportintheupcomingyears.Asthiscaseisadepictionofanauthenticevent,wewill
also use the data collected to reflect on the actual decisions and developments made by Logan
Airport.Wewill includeasmallcomparisonwiththereal lifedecisionsmadeandfromthiswewill
recommendouropinionsonwhethercorrectdecisionsweremadeandhowourdecisionsmayhave
differedgiventhe20/20hindsightwehaveregardingLoganAirport’sapproachtoagrowingvolume
ofpassengers.
PeakPeriodPricing’sImpactonDelayTimesandCosts
In the 2000s, Logan Airport in Boston has faced various problems regarding plane delays.
Severalmethodshavebeenproposedinordertoreducecongestionandaircraftdelays.Oneofthe
solutionscouldbe touseapeak-periodpricingmethod,whichwouldcharge theaircraftsahigher
rate during period of high capacity utilization in order to reduce runway traffic at that time, and
therefore,delays.Duringpeakperiods,thearrivalratesrangefrom45toalittleover60planesper
hour.Wehaveanalyzedthedelaytimesandassociatedcostsduringpeakperiodforthreetypesof
planes.(Turboprop,RegionaljetandConventionaljet)Foreachaircrafttype,wehaveanalyzeddelay
costsatthreelevelsofserviceat50,55and59planesperhourtogaugetheimpact.Werealizedthat
thetotaldelaytimeinthecaseof50planesperhourwouldbe6,55min.Then12,52minofdelays
wouldberegisteredfor55planesperhourandmorethan1hour(60,50min)foranarrivalrateof59
planesperhour.Moreover,allthesedelayswouldleadtosignificantcosts.Thetablebelowindicates
thecosts(in$)ofbothoperationalandpassengerdelaycosts.
Turboprop Regionaljet Conventionaljet
50planes/hour 75,25199999
167,9454545
467,2909091
55planes/hour 143,9603478
321,2869565
893,9478261
59planes/hour 695,6067227
1552,436975
4319,495798
Figure1:Delaycostsperaircraftperservicerate
The Federal Aviation Administration (FAA) estimated that a flight delayed would be only
takenintoconsiderationifithasadelayofmorethanfifteenminutespastschedule.LoganAirport
couldbenefit fromthisdefinition in termsof costs.Theoperational costswould remain thesame.
Whether thedelay is taken into considerationor not, theoperational costs (fuel, pilot,workers…)
wouldremainthesame.However,itcouldbeinterestingforLoganairporttotakeintoconsideration
theFAA’sdefinitionofdelayregardingthepassengercosts.Indeed,thesecostswouldnotbepaidfor
anarrival rateof50and55planesperhourbecausethedelayestimatedperplane is less than15
minutesandarethereforenotdeemedasflightdelay.Givenourfindings,wecanseethatreducing
thearrivalrates leadstocostreduction. Inouranalysis inthetableabove,datashowsthatapeak
with59planeshaswayhighercoststhanforexample50planesperhour.Thedelaycostsassociated
with50Turboprop’sarealmost11timeslessthantheTurbopropof59planesperhour(thisisalso
applicablefortheotherplanetypes).
PeakPeriodPricingandtheAirplaneMix
Our analysis of the operational inefficiencies at Logan Airport will now be examined by
incorporatingthe impactofpeak-period landing feesonthethreedifferenttypesofairplanes. It is
stated that airlines are only willing to shift flights to off-peak periods if costs of incurring peak
chargesoutweighthecostsofshiftingflightstooff-peakperiods.Thishesitancyismostlyduetothe
airlines’ fears of angering their customers, possibly resulting in a significant loss in revenue and
returningcustomers.
Peak-period landing fees have an immense impact on revenues and profits of specifically
smalleraircrafts incomparisontothemoreconventionalaircraftsduetothefees’negative impact
ontheprofitabilityofeachflight.Inresponsetotheselandingfees,someairlineswillfaceadifficult
decisiontochangetheirflightstooff-peakperiods,raisepricesorevencanceloperations.Giventhis
general information, we will now investigate how differently priced landing fees impact the
profitabilityofeachtypeofaircraftutilizingLoganAirport.
Westartouranalysisbycalculatingtherevenueperplaneforeachmodelgiventheseating
capacityandrevenueperperson.Givenourassumptionof70%loadfactor(seatsoccupied),wefind
total revenue per plane to be 70% of the plane’s total revenue. With the total revenue of each
aircraft,wecanthensubtracteachlandingfeeamountof$100,$150or$200.InTable2.1youcan
seeourcalculationsforeachkindofplaneandthedecrease inrevenueperplaneforeach landing
fee amount. With this data, it is already apparent that the per-flight revenue of the Turboprop
aircraftswillendurethemostsignificantdecreaseincomparisontotheotheraircraftmodels.
Plane Seating Revenue/person Total
Revenue
TR with
70%
load
minus
$100
minus
$150
minus
$200
Turboprop 19 230 4.370 3.059 2.959 2.909 2.859
Regionaljet 50 154 7.700 5.390 5.290 5.240 5.190
Conventional
jet
150 402 60.300 42.210 42.110 42.060 42.010
Figure2:Revenueperplanegivenaloadingfactorof70%andtheeffectofPPP
Beforewecanassesstheeconomic impactofthese landingfeeswillbe,wemustcalculate
themarginofoperatingprofit.Wedo this calculationby taking the totaloperatingprofit ($) from
eachplaneanddividing thiswith the total revenues ($)of eachplane. This givesus theoperating
profit margin of the planes. As you can see in Table 2.2 the Turboprop aircraft has an operating
marginof2,74%,theRegionalJethasan11%operatingprofitmarginandtheConventionalJethasa
margin of 12,22%. Given the drastic difference in operating margin between the Turboprop and
Regional Jet,we can already suggest that the Turbopropwill bemost significantly affected theby
demandmanagementthroughpeak-periodlandingfees.
Figure3:CalculationoftheOperatingProfitMargin
Plane OperatingProfit[$] TotalRevenues[$] OperatingMargin[%]
Turboprop 4.000 146.000 2,74%
RegionalJet 52.821 480.021 11,00%
ConventionalJet 2.365.000 19.352.000 12,22%
Withtheoperatingprofitmarginknown,wecannowcomparethisvaluewiththeeffectof
thelandingfeesonthetotalrevenueperplane.AsyoucanseeinTable2.3,ourcalculationsofthe
landing fees impacton total revenue represents thedebilitatingeffect these feeswill haveon the
profitabilityof theTurbojet.Atall three levelsof landingfees, theoperatingmargin (2.74%) is less
than the landing fees impact on revenues. Given this observation, Turboprop flightswill never be
abletoturnaprofitduringpeakperiods.InthecaseofRegionalJets,thefeeswillhaveareasonably
significanteffectontheflightprofitability(dependingonwhichfeeisused),butprofitsarestillthere
tobemade.Additionally,wecanseethatevery landingfee for theConventional Jetsbarelyaffect
theiroperatingprofitmargin,representingtheirabilitytowithstandpeakperiodpricingandcontinue
normalflightoperationswithinLoganAirport.
Plane DecreaseinRevenue(%)
$100fee
$150Fee $200Fee Operating Margin
(%)
Turboprop 3,27% 4,90% 6,54% 2,74%
RegionalJet 1,86% 2,78% 3,71% 11,00%
ConventionalJet 0,24% 0,36% 0,47% 12,22%
Figure 4: Comparison between the effects of landing fees on the revenue per plane with the
OperatingProfitMargin
Givenourpreviousanalysis,wecanconcludethatpeak-periodpricingwillhaveasignificant
effect on themix of airplane classes utilizing Logan Airport during peak periods. For instance, an
airplanemodelmixof40%Turboprop,18%RegionalJetsand42%ConventionalJets,willbehighly
impactedbytheimplementationofpeakperiodpricing.Thisisduetothe40%ofTurbopropmodels
thatwillcanceloperationsduetotheir inabilitytomaintainprofitabilityduringthesepeakperiods.
This 40%of Turboprop flightswill bedistributedbetween theRegional Jets andConventional Jets
duringpeakperiods inhopesofminimizingdelay costs causedby amixof aircrafts attempting to
utilizethesamerunwaysduringthesameperiods.Duringpeakperiodpricing,wecanseethatthe
operatingprofitmargin for theConventional Jets isminimally affected. Therefore,wepredict that
therewillbealargerincreaseinConventionalJetaircraftsatLoganAirport,whichwillbecapableof
withstandingthenegativeeffectsofpeakperiodpricinguntilahigherfeeisestablished.
Givenadecrease inTurbopropsoperatingduringpeakhours, themagnitudeofdelayswill
alsosignificantlydecrease.IfrunwaysarelimitedtoRegionalandConventionalJets,therunwayscan
be used more effectively and efficiently for arrivals and departures. Given the fact that smaller
aircraft hold fewer passengers, flymore slowly and are required tomaintain greater distances to
avoidwindvortexesfromlargeraircraft,attemptingtomixthesemodelsintopeakperiodswillonly
servetoincreasedelaytimesandultimatelycosts.
Withtheseobservations,wecanassumethatamixofairplanescontaining20%Turboprops,
30% Regional jets and 50% Conventional jets, will have far less significant implications on the
magnitudeofdelaysatLoganAirport.DuetothefactthatTurbopropaircraftsonlyaccountfor20%
of flightsduringpeakperiods in thisexample, theuseofpeakperiodpricingand landing feeswill
significantly impact a smaller percentage of flights than in the previous scenario. Seeing as the
majorityof flightsduringpeakperiodsare largeraircrafts in this scenario,wecanassumethat the
magnitudeofdelayswillbe lesssignificant influencedwithpeakperiodpricing.Byonlyhavinghalf
theamountofTurbopropsflyingduringpeakperiods,delaytimesandcostsautomaticallydiminish,
makingtheuseofpeakperiodpricinglesssignificantwithinthismixofaircraftsthantheformermix.
Asa resultofdemandmanagementand theuseofpeakperiodpricing, smallerTurboprop
aircraftswillbeforcedtocanceloperationsduringpeakperiodsduetoaninabilitytocreateprofits.
Giventhischange,Turbopropaircraftswillbegintooperateduringoff-peakperiods,spreadingout
flightoptionsandminimizingcongestionduringpeakperiods.Duetotheamountofdelayscausedby
the inefficiencies and slow nature of the departure/arrival process for Turbojets, eliminating their
useduringpeakperiodswilldramaticallyincreasesavingsindelaycosts.Forthelarger,Regionaland
Conventional aircrafts, the absence of Turboprop aircrafts during peak periods will minimize the
delaycostsandimproveaircraftturnaroundtimeontherunwayandatthegate.Bylimitingtheidle
timeandwastedminuteswaiting forTurbojets to clear theway, the fees thatareassociatedwith
operatingduringthesepeakperiodswillultimatelybeoffset.
TheImpactofWeatherConditionsontheArrivalandServiceRates
Thecapacityof theairport ingoodweatherconditionsaverages60planesanhour.During
moderateweatherconditions,45planesanhour.Duringsevereweatherconditions,theairportonly
averages30planesanhour.TheservicerateofLoganAirport isdirectlycorrelatedtotheweather
conditions.Therefore,ifarrivalrateexceedstheweather-variablecapacity,waitinglineswilloccur.
TheLoganAirportcaseshowsthat90%ofallflightswerenon-transitionflights.Thismeans
thatflightsarrivemoreuniformlyovereachhourratherthanclusterinhourlylumps.Duetothis,the
airportonlyhasasmalltimeframetorecover,beforetheplanescomebackfromtheotherairportto
Logan.Thisdoesnotgivetheairportanytimetoreduceitspendingwaitingline,sincearrivalrates
are not expected to drop during the normal flight schedule. As long as the inclement weather
persists,thewaitinglineincreases.Moreover,thelongerthewaitinglinegets,thelargertheeffect
onthevariabilityofarrivaltimes.Keepingaircraftsinholdingpatternslongerthanplannedrequires
themtoburnmorefuelthaninitiallyanticipated,whichincreasescostsincurredbytheairline.
Bycalculatingthedelaysduringdifferentweatherconditions,somesevereproblemsbecame
clear.Wecalculatedthedelaytimeandcost forthreedifferentsituations.Thefirstsituation isthe
goodweathercondition.Inthisconditionthethreerunwaysareopenwhichmeansthattheairport
functionsatit’shighestcapacity.Duringgoodweatherconditions,delaytimesareminimalatmost.
Theonlydelayweobserveisat18.00handthisisadelayofonlyoneminute.Althoughthisminute
delaycanbesolvedquickly,wenotedthatitdoesresultinacostof39,20dollars,whichshowsthat
eventheslightestdelaysresultinhighcosts.
Thesecondsituationisthemoderateweathercondition.Thismeansthatonlytworunways
areusedandthatthecapacitydecreases.Atmoderateweatherconditionsalotofproblemsoccur.
Thedelaysalreadystartat8hwithadelayof12minutesanditquicklybuildsupuntiladelayof47
minutesat17h.Itisimportanttohighlighttheproblemofqueuing.Whenplanesarrivetoolate,they
create a waiting line, as explained above. Due to the fact that flights continue to arrive, the line
keeps expanding. Given the degree of delays, it takes several hours after the peak periods to get
resolvetheproblemsandeliminatethewaiting line.Thecostofsuchawaiting line ismassive.For
example,at17hawaitinglineof47minuteshasanaveragecostof$914.
Thelastsituationisthesevereweathercondition.Duringthiscondition,onlyonerunwayis
inoperationandcapacity isat its lowest.Delaysbegin to takeeffectat6hwithawaiting lineof4
minutes.Thewaitingperiodgrowsquicklytoalmosta7-hourwaitinglineat17handalmost9hours
at20h.Theproblemofqueuingoccurshereaswell.Thecostsaredramaticallyhighfrom7.762dollar
at17handeven10.271dollarsat20h. Inaddition, itmustbenotedthatflights,whicharedelayed
for more than 2 hours, will never depart, creating a huge impact on the overall operational and
passengercostsassociatedwiththeflight.
Apossible solution todecrease thedelay times isbybuildinganewrunway,whichcanbe
usedduringsevereweatherconditions.Withtheconstructionof this runway,minimalmajordelay
timeswouldberegistered.Addingatleastoneadditionalrunwaywouldpartiallyalleviatethedelay
concernsandminimizedelaycosts.
Figures5and6belowshowwhathappenswhenweaddanadditionalrunway.Wewillnot
do this whenweather conditions are good as this gaveminor delays.We assume three different
capacitiesof thisadditional runway.This is+10,+20or+30additionalarrivalsperhour.Thegraph
shows that during the moderate weather conditions, an additional 10 arrivals almost eliminates
delayproblems.Inthesecondgraphwecanseethatanadditional30arrivalsanhourduringsevere
weatherconditionsisneededtocopewiththedelayproblems.
RecommendationsonPeakPeriodPricingand/ortheAdditionofaNewRunway
Givenour findings in theanalysisabovewehavereachedaconclusiononwhatwebelieve
wouldbethebestapproachatLoganAirportinrelationtominimizingthemagnitudeofdelaysand
theoperationalandpassengercostsassociated.
First,wewouldrecommendtotheFFAinBostonthatwebelieveintheuseofanadditional
runwayandendorseMassport’s constructionof a runwayat LoganAirportdespitepushback from
severalgroups.Giventhecurrentmagnitudeofdelayscausedbythelimitationsofourrunways,we
believeanadditionalrunwaywouldalleviateseveraldelayissues.Forexample,anadditionalrunway,
0
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0h
2h
4h
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8h
10h
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Waitingline
Figure5:ModerateweathercondiQonswaiQngline/hour-capacity
MWCwaitingline
MWCwaitingline(+1runway+10)
MWCwaitingline(+1runway+20)
MWCwaitingline(+1runway+30)
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Figure6:SevereweathercondiQonswaiQngline/hour-capacity
SWCwaitingline
SWCwaitingline(+1runway+10)
SWCwaitingline(+1runway+20)
SWCwaitingline(+1runway+30)
positionedinawaythatisresistanttosevereweatherconditionswillimproveLoganAirport’sability
to maintain a satisfactory turnaround time for all of its aircrafts during peak periods or times of
severe and inclementweather. Due to the fact thatwinds approaching from theNorthwest force
Logan to reduce operations down to one runway, creating the ability to better cope with these
weathereventswillgreatly reducedelaycosts.Additionally,webelieveMassport’sconstructionof
anotherrunwaycanassistinreducingdelaytimesrelatedtotheuseofafleetofaircraftsthatvaryin
size and turnaround time. If we were to assign a specific runway to just Turboprop aircrafts, we
wouldefficientlylimittheamountoftimethelargeraircraftsmustwaitfortheseTurbopropstoclear
the runway. By designating smaller aircraft to their own specific runway, we can resolve the
magnitudeofdelayscausedbyacomplexmixofaircraftsutilizingthesamerunwaysduringthesame
timeperiods.
Due to the growth in the amount of passengers predicted to use Logan Airport in the
upcomingyears,wealsoseePeakPeriodPricingasausefulandnecessarytooltocopewiththehigh
magnitudeofdelaysbeingexperiencedatLogan.Webelievethatbyinstatingapeakperiodpricing
strategy,wewillencouragepassengerstoflyduringamorewidespreadrangeofflighttimes.Ifpeak
periods are associatedwith high landing fees, wewill discourage smaller aircrafts from operating
during these periods andwill either cancel operations ormove them to off-peak periods, both of
whichwillimprovedelaytimes.Webelievethatthelongtermeffectsofpeakperiodpricingwillbe
positive,asthegrowthinpassengersatLoganispredictedtocontinuouslyexpand.Withastrategy
thatencouragesTurbopropoperationsduringoff-peakperiods,LoganAirportwillbeabletobetter
utilize the runwaysduringpeakperiodsbypredominantlyusing theconventionaland regional jets
that require less turnaround time and space for takeoff, while also transporting a much higher
numberofpassengersperflight.
Sowhatreallyhappened?
Givenourfindingsandrecommendationstoaddbothpeakperiodpricingandanadditional
runway to cope with the magnitude of delays at Logan Airport, we will now divulge the actual
decisionsmadebytheofficialsinrelationtothesetopics.Oncebeingproposedin1973andenduring
40yearsofdelaysduetodisagreementsovertherunway’sfeasibility,finallyonNovember23,2006
runway 14/32 became operational. This runway is now used for both departures and arrivals. To
addressdelayscausedbyinclementweatherconditions,LoganAirporthasdesignatedtheuseofthis
runwaytoconditions thathaveaminimumwindthresholdof19km/h fromthenorthwest. In2009
theyalso finishedwith thebuildingofanewtaxiwayparallel to runways4R/22Land4L/22R.They
started constructing this taxiway in 2007 with approval of the FAA. Logan Airport in Boston now
operatessixrunwaysthatarealignedinthreedifferentdirectionsinordertosufficientlycopewith
windsandinclementweatherapproachingfromalldirections.Giventhisnewrunwayconfiguration,
Logan Airport can accommodate 120 operations per hour when the FAA can use a three-runway
system. In the event of poor weather conditions, the operations per hour can be reduced to 60
operations.
Given these decisionsmade by the FAA at Logan Airport regarding the expansion of their
runway configuration, we must also note that the officials didn’t see peak period pricing as the
primarysolutiontobeusedinresolvingtheirdelaydilemma.Throughoutthe2000’s,theuseofpeak
period pricing to cope with delays during peak periods was frequently considered. Due to Logan
Airport’spositioninginBostonasafarnortherncoastalcity,theyplacedahighlevelofimportance
ontherelationshipswithTurbojetpassengersthatoriginatedfromregionsthatwereusersofsmaller
aircrafts.LoganAirportofficialswerewaryofthedeterioratingeffectpeakperiodpricingmayhave
onthelongtermrelationshipsbetweenthemselvesandtheirTurbojetcustomers.
Figure7:NewRunwayConfigurationasof2006
Work(s)Cited
1. Andersson, Kari, Francis Carr, Eric Feron, and William D. Hall. "Analysis, Modeling, and
Control of Ground Operations at Hub Airports."Air Transportation Systems
Engineering(2001):305-41.MIT.edu.16June2000.Web.1Dec.2015.
2. Idris, Husni R., BertrandDelcaire,WilliamD. Hall, John-Paul Clarke, John R. Hansman, Eric
Feron, and Amedeo R. Odoni. "Observations of Departure Processes at Logan Airport to
Support the Development of Departure Planning Tools." (1998): n. pag.Atmseminar.org. 4
Dec.1998.Web.1Dec.2015.
3. Narayanan,V.G. "Delaysat LoganAirport."Review.HarvardBusinessReview13Dec.2001:
Print.