Drop Testing Airtankers:
A Discussion of the Cup-and-Grid Method

United States Department of Agriculture
Forest Service
Technology & Development Program
Missoula, Montana

5700 Aviation

TE92P32—Technical Services, Aerial Delivery

December 2000

Ann Suter

Figure 16—Drop pattern characteristics for the Sims 2,000-gallon helibucket with a drop speed of 83 knots and a drop height of 119 feet.

Table of Contents


Mechanics of the Release

History of the Cup-and-Grid Method

Alternative Methods of Analysis



About the Author

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