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Cost of Delay, Rescheduling andCancellation In AirlinesIntroductionUsually Airlines are suffering from flights delay issues, butmost of them control these problems and their causes, so theissue of flight delay may create a bad impression on the airlineimage and its brand name in the market, and consequently it isdirectly related to the concerned airline operation divisions anddepartments, from maintenance, flight operation, commercialand customer service, as they are interacted and integrateddivisions that serve for one mission, so every division has itsown rules and impacts on dispatch the flight on time, and anynegligence may reflects on airline final performance, and cause Mohammed S. Awadthe delay of the flight. In aviation industry the cost of delay is Research Scholarconsiderably high due the high gained revenue of the flights and high direct fixedoperating cost for a certain type of aircraft hence we measure the activities of anairline by its performance which usually addressed by the performance report ofOperation Control Committee OCC. Where the maintenance and material divisionsare the main airline departments that support the operation, as they are responsible foraircraft technical readiness and fulfill the provision of spare parts of the aircraft, andtracking/ monitoring the technical operating performance by papering reliabilityreport, which is similar as performance report, but its results are technical oriented, i.edefining technical problems and failure diagnostic before its happen and cause a delayor cancelation, which play a major rule in preventive maintenance program for theaircraft. Finally by referring to Boeing Company reports, the engineering andmaintenance issues and problems for aircraft are represents 30-40% of total delaycost for the flight in airline industry.1

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OCC Operation Control Committee:The weekly report of this committee is oneof the main sources of airline activityevaluation and it is an effective tool toexplore and define deviations so a properaction may take on time and most ofoperating and serving departments representsin the committee, so this report rise theinitial signals to predicate defect or trouble acertain failure in the airline activity for oneweek period.Delay Cost:It is too complicated to evaluate andcalculate the delay cost in the airlineindustry and its impacts on the image and thebrand of the airline. So we can refer toBoeing terms and definitions for delay costthat addressed in AGIFORS - Denver which are 1- Passenger direct cost 2- Direct Operating Cost 3- Cost of unavailability of scheduling Aircraft 4- Cost of losing the image and the loyalty for the airline.In our case we will use only two factors in the analysis only: 1- Passenger direct cost 2- Direct Operating Costthe calculation of delay or cancellation costwill as the following:Direct Operating Cost + expected incomerevenue of the delay or cancelled flight.And according to the study of AmericanAirlines – domestic routes, the results are :Delay from :0 – 15 minute.......... No Calculation of Cost16 - 60 minute….......0.25 % ticket/min/pax1 – 2 Hours ……0.5 % ticket /min/pax Approximately 1 out 8 passengers willprobably not buy their next ticket on this airline.2 – 5 Hours …….... All passengers will probably not buy tickets on this airline againfor at least a year. And in this stage the growth of delay cost increase exponentiallyuntil reach to 5 hours delay period ( out of business).2

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While the next figure explain the relationship between these costs and its averagevalues, indicating the direct cost of passenger may happen after 20 min of delay time,and its impact on the passenger loyalty, image and the brand value of the airline.Impacts of Engineering andMaintenance:Referring to the Boeing Study, theshare impact of maintenance andengineering causes may reach 30-40of total delay causes. And thetechnical causes are the mainreasons for cancellation of the Figure ( 2 ) Delay Cost Elements - American Airlines Study.flights and as its shows in theprevious figures, the maximum delay period for maintenance cause is 45-120 if thereis no cancellation. And the consequential effects of late aircraft arrival play a majorrule in rescheduling the flights again.Delay Cost - Yemenia Case Study:The period of 02/01/2010 to12/03/2010 characterize by repeatedmany delays in flights –Yemenia.Among of that , the technical delaysand engine failures of B737-800fleet which create a total mess in theflight scheduling program. So thedelay cases can be address in twodirectionsFirst : counting the repeated delaysissues Figure ( 1 ) Measuring the time period costsSecond : the delay time American Airlines Study.So delays can be caused by one of the following reasons: 1- Delay of the flight of the same aircraft type. 2- Delay of the flight may cause the need to change the type of the aircraft from bigger to smaller capacity which lead to extra cost of spill passengers. 3- Delay of the flight may cause the need to change the type of the aircraft from smaller to bigger capacity which lead to extra cost of losing the opportunity of un utilize seats for sale in last minutes. 4- Aircraft Grounded cost, by sending another aircraft for taking the passengers and supported spare parts. 5- Some time suddenly two aircrafts ground in the same time, and rise a hard time for planners and consequently may lead to cancel the flight. 6- Un readiness of the aircraft for unexpected time. 7- Longer maintenance programs may lead to delay the flights.3

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Figure ( 3 ). Delay Factors of Yemen AirwaysAnalysis:In spite of defining Boeing Company the main factors that may cause the delays,pointing out the maintenance /engineering and bad weather but yemenia analysisresults indicates another factors that impact high influence of those mentioned inBoeing Study. However technical and engine failures remains the main factor in theperiod of 02/01/2010 to 12/03/2010 1- Transit Passengers 2- Technical Problem 3- Airport Security 4- ATC 5- Late Arrival of Aircraft 6- Bad Weather 7- Maintenance Problems 8- Other factorsAs indicated in graph, the other factors take the large share in the delay reasons,yemenia should review all the delay items category so that the other reasons welldefined in the analysis and re casted in the right way. Also similar category should bemerge to be one category as maintenance and technical. This lead us to the result of the analysis, soNumber of Delayswith less than 20 min =121 delayswith cumulative time = 1355 minNumber of Delayswith greater than 20 min =87 delayswith cumulative time = 4185 minbut for technical delays, it take larger time to fix and rectify in spite of hiddenfunction issues4

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Summary: 1- The analysis show the un availability of support fleet , as the scheduling designed with one supported aircraft. But in some cases of two aircraft grounded in the same time led to a total mess in scheduling that need to rescheduling and delay the other flights. 2- The technical delay have the majority causes of delays, and when its happen , its take a long time. 3- In spite of the impact of transit passengers on delay, the maximum allowable time period for transit passengers is 45-60 min, but the delay period may reach to 5 hours or more and effects on the airline image in the market. 4- Advanced and prior corporation between commercial and technical departments so that they adapted and implemented a the right scheduling without interruption based on the sound of the market. 5- Brand name of the airline in the market may get lose, if the airline repeat these delays, and changing the capacities of aircrafts in the last minutes. Figure ( 4 ) Frequency Distribution of Delay Periods 5