Investigation of the drag of small-sized aircraft in the presence of a longitudinal central through channel

The paper presents the results of ballistic experiments to study the possibility of reducing the drag of small-sized aircraft, for example, bullets of the Match type for pneumatic weapons by upgrading their shape. The authors proposed the creation of a through cylindrical channel along the longitudinal axis, which ensures the flow of gas from the high-pressure zone in front of the bullet head to the low-pressure zone in the tail track. 5 types of bullet modifications with channels of different diameters are considered. The studies were carried out both with the admission of reversible air flow at the time of the shot, and with its exclusion. As a result, positive effects were identified for certain variants and a decrease in drag of the proposed modifications was estimated.

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