Cover Image

Not for Sale



View/Hide Left Panel
Click for next page ( 66


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 65
65 Cost to develop, publish, and approve new procedures; Model Testing Cost to include new procedures in airline deicing program The cost-benefit model was refined and validated through a and get approval; testing process. The testing process involved running the devel- Cost to develop training materials for spot deicing; oped model through a variety of scenarios and situations cre- Cost to move frost deicing from remote location to gate*; ated by inputting various parameter values representing both For both standard and spot frost deicing: annual equipment typical and extreme operations. This process confirmed that maintenance costs and annual equipment operation costs; the model can provide reasonably accurate outcomes for a Additional flight crew and ground crew training costs for variety of situations and users. spot deicing; Contractor cost, block time cost, glycol cost, staff cost, inspector cost, and cleanup; and Findings and Applications Cost per deicing for both standard and spot frost deicing*. The findings and applications of the work completed to examine the current practices and regulations, opportunities, All inputs are not required in all scenarios. limitations, obstacles, and potential benefits associated with the usage of spot deicing for frost removal are discussed in this Model Output section: The primary output of the model is the number of years Findings of the literature review; until initial investment is recouped (years to breakeven). The Results of laboratory tests; financial and glycol savings to be gained annually by imple- Findings of the focus group survey; and menting spot deicing for frost are also calculated. Application of findings to create cost-benefit model. The annual financial savings are determined by: Comparing the annual fixed costs of standard frost deicing Examination of Current Government only with the annual fixed costs of operating with a mix of and Industry Regulations, Guidance standard and spot frost deicing to determine the annual Material, and Standards fixed cost expense or savings; Comparing the per-deicing variable cost of standard frost Aircraft ground deicing procedures used by most North American air carriers are prepared by the airlines and are based deicing only with the per-deicing variable cost of a spot on general guidance information contained in the appropriate frost deicing to determine the variable cost savings per spot aircraft manufacturer's maintenance manuals, aircraft deicing frost deicing conducted; and Multiplying the variable cost savings per deicing by the industry documents, and regulatory guidance. Specific guide- lines for deicing are contained in SAE, AEA, FAA, International number of spot deicings that will be conducted (total Civil Aviation Organization (ICAO), and Joint Aviation annual frost deicings times percentage of frost deicings that Authorities (JAA) documents. Of these documents, SAE ARP will use a spot frost deicing procedure) and adding the 4737 is the premier document and is referenced by all major air annual fixed cost savings (or subtracting the annual fixed carriers internationally. cost expense). The annual glycol savings are determined by: SAE There are two SAE documents where guidance on spot Multiplying the annual glycol consumption by the addi- deicing procedures may appear: ARP 4737 (Aircraft De/Anti- tional glycol required for a standard deicing relative to a spot Icing Methods document) and ARP 5149 (Training Guide- deicing multiplied by the percentage of frost deicings that lines for Deicing and Anti-Icing Aircraft on the Ground). will use a spot frost deicing procedure. At the time the literature review was conducted, there were no specific guidelines in either of the SAE documents that The years to breakeven are determined by: addressed procedures for spot deicing for frost removal. The general guideline in ARP 4737 for removal of frost and light Comparing the annual financial savings of implementing ice, i.e., paragraph 6.1.2.2, simply stated: spot deicing for frost to the initial investment required (set- up costs and capital costs) and determining how many A nozzle setting giving a fan spray is recommended. NOTE: years it will take for the annual savings to pay for the initial Providing that the hot fluid is applied close to the aircraft skin, a investment. minimal amount of fluid will be required to melt the deposit.