The National Academies Press

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From page 56... ... At remote deicing facilities, where aircraft are deiced with engines running, reduced engine run-time lowers fuel burn and its related carbon emissions, and lowers aircraft operating costs. Several other relevant features of spot deicing for frost removal are: • Additional operator and flight crew training is required to implement this procedure; • Adoption of this procedure requires closer checking and inspections by qualified personnel; and • Conventional ground deicing equipment, suitable for normal defrosting usage, can be used to perform spot deicing for frost removal. Read the entire page →
From page 57... ... Recommendations for De/Anti-Icing of Aircraft on the Ground. Laboratory Tests Laboratory tests were conducted to collect data to support the development of guidance material for spot deicing of frost, specifically to provide procedural guidance on fluid strength, fluid temperature at application, and fluid amounts. Read the entire page →
From page 58... ... If its application in active frost conditions is deficient, then field operators must be cautioned that an unsafe condition may result from such use. Because of this concern, test procedures were developed to examine spot deicing during both non-active and active frost conditions. Read the entire page →
From page 59... ... Spray method for fluid application on a test plate surface. Figure 21. Read the entire page →
From page 60... ... Baseline Test #1 was similar to the procedure used in holdover time testing in active frost conditions except the frost was not removed from the test surface prior to fluid application. Baseline Test #2 was a baseline test for spot deicing, and was based on results from preliminary tests conducted during outdoor active frost conditions. Read the entire page →
From page 61... ... Chamber temperatures for Test Sets 1, 2, 3, and 3a were lower than planned due to the location of the test stands in the cold chamber. For the remaining tests, the stands were repositioned to an area of the chamber where temperatures were more suitable. Read the entire page →
From page 62... ... The applicability of some of the questions in the survey was determined by respondents' answer to Question 7, which asked if their affiliated organization was currently using the spot deicing methodology, planned to use it in the future, or did not plan to use it in the future. The survey software was used to route respondents to the appropriate questions based on their response to this question. Read the entire page →
From page 63... ... The preliminary examination addressed the effect of spot deicing individual aircraft, but did not extend to the overall deicing process because of the complexity involved. The introduction of spot deicing may substantially change the local Table 41. Read the entire page →
From page 64... ... Similarly, the preliminary examination assumed no change to deicing times and thus no effect on costs, whereas a relocation of the frost deicing from remote facilities to on-gate deicing may have a considerable effect on aircraft block times, which are high value factors. Thus the final model incorporated several parameters not included in the preliminary examination. Read the entire page →
From page 65... ... This process confirmed that the model can provide reasonably accurate outcomes for a variety of situations and users. Findings and Applications The findings and applications of the work completed to examine the current practices and regulations, opportunities, limitations, obstacles, and potential benefits associated with the usage of spot deicing for frost removal are discussed in this section: • Findings of the literature review; • Results of laboratory tests; • Findings of the focus group survey; and • Application of findings to create cost-benefit model. Read the entire page →
From page 66... ... To assess frost severity for non-active frost deicing, the frost amounts for the various test sets were simply compared, using the highest as the base case. The results shown in Table 43 indicate that test surfaces for test sets 3b, 3c and 5 had collected considerably more frost than for the other test sets. Read the entire page →
From page 67... ... Quantity of Fluid Needed to Remove Frost Results from both active and non-active frost tests generally indicated that 10 mL of fluid was not enough to cover and deice the entire surface plate area, 20 mL was barely enough, and 40 mL was sufficient to remove frost from test plate surfaces. Results for Spot Deicing in Non-Active Frost Forty (40) Read the entire page →
From page 68... ... . Of the eight test sets, only three experienced an active frost rate considered to be more than light frost (Table 44) Read the entire page →
From page 69... ... Disclaimer: This model has been prepared by APS Aviation Inc. for the Transportation Research Board. Read the entire page →
From page 70... ... at the spray nozzle; • Unless further testing is conducted and proves otherwise, spot deicing should be used only for non-active frost conditions; and • Additional testing with positive results would be needed before spot deicing could be approved for active cold-soak frost deicing. A group of key individuals from the deicing industry were surveyed to gather a more thorough and detailed Read the entire page →
From page 71... ... Cost to develop training materials for spot deicing 5,000$ e) Cost to move frost deicing from remote location to gate 5,000$ FIXED COSTS - ANNUAL Costs for standard frost deicing : a) Read the entire page →
From page 72... ... If implementation of spot deicing enables relocation of the defrosting activity from remote sites to passenger terminal gates, very significant benefits can be achieved in reduced operating costs, improved on-time performance, and reduced environmental impact from spent fluid and from carbon emissions due to fuel burn. Recommendations The following recommendations resulted from the work conducted for the spot deicing for frost removal task: • Although it does not appear to be required in order for operators to implement spot deicing for frost removal, it is recommended that the regulatory authorities (FAA and 72 RESULTS Fixed Costs of Frost Deicing (per winter season) Read the entire page →
From page 73... ... (These changes are deemed to be minor editorial changes.) • It is recommended that spot deicing be applied only to nonactive frost resulting from natural frost generation. Read the entire page →

From page 56...

... At remote deicing facilities, where aircraft are deiced with engines running, reduced engine run-time lowers fuel burn and its related carbon emissions, and lowers aircraft operating costs. Several other relevant features of spot deicing for frost removal are: • Additional operator and flight crew training is required to implement this procedure; • Adoption of this procedure requires closer checking and inspections by qualified personnel; and • Conventional ground deicing equipment, suitable for normal defrosting usage, can be used to perform spot deicing for frost removal.