# 9663 / Year-Round Measurements Of The Soil Cone Index On Grass Airfields For Ground Performance Of Airplane ## Authors Jarosław Pytka, Anna Zalewska Tytłak, Paweł Tomiło, Michal Kuszneruk, and Dawid Tatarynow {% hint style="info" %} Paper presented at ISTVS 2024 | 21st International and 12th Asia-Pacific Regional Conference of the ISTVS\ Keywords: Cone Index; Grass airfield; Airplane performance; Weather impact\ {% endhint %} ## Abstract The paper concerns the performance of ground-based aircraft operating from grass airports, in particular the take-off and landing distances. These performances are strictly dependent on the conditions on the runway, and in the case of a grass runway, they depend on the influence of weather factors. Year-long measurements of the soil cone index were carried out on the runways of 5 grass airports, which are characterized by different ground soils. The measurements were carried out in the period from July 2019 to June 2020. The paper presents a statistical analysis of the measurement results. Generally, it was found that weather factors have a significant impact on the values of the cone index and changes in the CI value reach up to 400% (the highest relative to the lowest). Moreover, it was observed that the type of soil underlying the grass on the runway had a significant impact on the CI index values. The most sensitive ground was marl, with a high chalk content, which constitutes the foundation of one of the tested grass airfields. The results will be used to parameterize and verify the model describing the road wheel and ground performance of the aircraft. *** Full paper purchase: \ ISTVS members receive three complimentary papers per year: --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://2024.istvs.org/submissions/papers/9663.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.