National Free Flight Society

SEN 3020

  1. Eifel Pokal Results
  2. Winning By Extrapolation

Eifel Pokal Results



Winning By Extrapolation

From aram Schlosberg
In SEN 3019 Gauthier Briere argues that altitude flyoffs (the altitude at 120 seconds) could be improved by calculating the theoretical flight time based on the (1) climb max altitude and the average sink rate between attaining the (2) maximum attitude and (3) the altitude at 120 seconds.

Besides depending on three observations, the extrapolation presumes that the calculated sink rate will remain CONSTANT between two and 7-8 minutes.

The sink rate of a good B model is around a third meter per second in “ideal” conditions. The main flaw is the premise is that the vertical velocity component of the particular air mass the model is flying in over 7-8 minutes will remain constant until landing.

Yes, there are SPACIAL and TIME differences among models in a flyoff. Line position, particularly in a large flyoffs; where models were launched in A; when the model was launched during the 7 minute window as well as the model’s orientation at the end of the motor/engine run or bunt and it’s glide circle.

All this is captured by the single observation (3) – the altitude at 120 seconds. It beats retrieving in distant corn or sun flower fields and almond groves in the dark. ///

Aram Schlosberg

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Roger Morrell