Click for next page ( 43


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 42
42 Table 9. MCO lightning event frequency stratified by time of day and season of year. Hour Dec-Feb Mar-May Jun-Aug Sep-Nov Total 0-3 1 1 5 3 10 3-6 1 2 2 5 6-9 1 1 2 9-12 2 1 1 4 12-15 2 1 1 4 15-18 1 11 1 13 18-21 2 2 38 9 51 21-24 3 5 20 9 37 Total 12 12 78 24 126 Following the approach taken for ORD, monetary values Certainly, for an affected disgruntled passenger, any delay over were calculated for typical duration events at MCO. The pri- 30 min would not be considered "short duration." mary difference in the results between ORD and MCO is Notwithstanding this possible interpretation of delay time caused by the difference in the number of aircraft affected by per lightning event, it is recognized that the focus of the re- the delay. The results for the MCO monetary value analysis search is on the economic impact to the airline and the air are presented in Table 11. transportation system. The key point here is that airlines can Again, following the analysis used for ORD, Table 11 esti- choose to undertake certain mitigation actions, such as re- mates the potential savings of a shortening of the duration of scheduling flights and crews at other airports, to compensate each ramp closure event by 10 min. The potential savings for missed connecting flights attributable to lightning delays from a 10-min improvement in delay time during peak hours at an airport. However, because this takes time to analyze and at MCO is approximately $2.8 million, compared with the implement, anticipated short-duration events are generally $6.2 million calculated for ORD. accepted and managed as best as possible. Furthermore, delays of less than 60 min produce comparatively minimal costs to the airline industry when compared with costs for delays of greater Shorter Duration Events than 60 min. As indicated in Table 8 and Table 11, the per- minute cost of a short duration delay averages 21% of that for Consideration was given to reducing the 60-min or less medium delay events and 14% of that for long delays. lightning delay interval in the cost analysis to a shorter time in- Generating shorter duration delays would thus have the terval. In fact, as shown in Figure 18 and Figure 19, a majority effect of reducing an already minimal cost contribution. Con- of the duration delay events are for periods of less than 60 min. sequently, we have chosen to use the three delay event strati- This would argue for a further stratification of the monetary fications indicated above because they provide a clearer view value analysis for "short duration" delays to include an analy- of which events produce the major costs and therefore pro- sis for delays of less than 30 min or perhaps less than 15 min. vide the focus for improvement. Table 10. Typical monetary values for various duration events during the 7 a.m. to 8 p.m. core period at MCO. Typical No. of Local Airport Cost ($) Ripple Effect ($) Per Type of Duration Aircraft Total Minute Event (min) Affected Direct Opportunity Direct Opportunity Cost ($) Cost ($) Short 30 20 0 28,600 0 42,900 71,500 2,383 Medium 120 80 6,254 457,600 181,680 686,400 1,331,934 11,099 Long 210 140 28,371 1,401,400 317,940 2,102,100 3,849,811 18,332