Articles with tag: "probability"

(Note: figures do not appear in the summaries below)

  1. Porter Perkins Flight Safety Publications

    "Most, if not all of the recent accidents on record having icing as the probable cause could have been prevented if the flight crews understood the serious nature of the situation and had applied appropriate corrective action." 2

    Summary

    Three publications on flight safety by Porter Perkins are reviewed.

    Discussion

    These publications are copyrighted. The first one, however, has a reuse license, and so much of the discussion will center on it.

    "Tailplane icing and aircraft performance degradation" 1992 1

    Ice on the tailplane (horizontal stabilizer) was identified as a risk on some aircraft:

    Although the sensitivity of airplanes to inflight icing has been recognized for many years and can be minimized by ice protection systems, the advent of the medium-altitude turboprop commuter transport aircraft has resulted in renewed attention to the icing problem. This review of icing has been prompted by several recent accidents that apparently were caused by …

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  2. Reproducing NACA-TN-2738 Calculations

    "In view of the number and complexity of the possible sources of error, it is not possible at this time to make a reliable estimate of the total accuracy" 3

    8-39 figure 10e. Calculations for Flight 8-39.

    Summary

    Calculations are made to assess the probability of encountering certain icing conditions.

    Introduction

    In Porter Perkins Ice Shapes and Ice Protection, references NASA TM 83564 1 and NASA TM 86906 2, the probability of encountering certain icing conditions was assessed, using methods from NACA-TN-2738 3. Here, we will attempt to reproduce those calculations.

    Discussion

    In NACA-TN-2738, data were divided by geographical region.

    Figure 1. Map of the United States showing approximate boundaries of areas used in the geographical classifications of icing data.

    The NASA Technical Memos did not state where the natural icing test flights were. However, as three of the authors were based out of the NASA Lewis Research Center, Cleveland, Ohio, I will assume that the flights operated out of there and were in the Eastern United States region.

    So, the appropriate chart to use is Figure …

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  3. Porter Perkins

    "As the demand for all-weather protection on aircraft for unimpaired and continuous commercial and military service developed, the detrimental effects of ... icing on airplane performance became increasingly important" (1948)

    Figure 1. Tunnel installation of hollow steel air-heated propeller for icing investigation. A tall, lean man with a distinctively tall nose inspects the propeller.

    From NACA-TN-1586. I believe that this is Porter Perkins, circa 1946.

    Summary

    Porter Perkins published on icing topics for over 50 years while at NACA, NASA, and other groups.

    Biographies and Memorials

    Porter J. Perkins is a senior aerospace engineer working in aviation safety as manager of airworthiness of research flight activity at the Lewis Research Center of the U.S. National Aeronautics and Space Administration (NASA), Cleveland, Ohio, U.S. He has specialized in research on aircraft icing for more than 25 years. His in-flight measurements to characterize icing clouds were later incorporated into U.S. icing protection certification standards. He has authored or co-authored more than 25 reports in the field of aircraft icing, and continues to participate in …

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