Drag Measurements of a Protruding .50-Caliber Machine Gun with Barrel Jacket Removed

Abstract

Tests were made in 8-ft high-speed wind tunnel to determine the drag reduction possible by eliminating the barrel jacket of a protruding 50-caliber aircraft gun. It was found that the drag of a standard aircraft gun protruding into the air stream at right angles to the flow can be reduced by 23% by discarding the barrel jacket. At 300 mph and sea-level conditions, this amounts to a decrease in drag of from 83 to 64 pounds. A rough surface finish on the barrel was found to have no adverse effects on the drag of the barrel, the drag being actually less at high Mach Numbers.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1943
Accession Number
ADA800655

Entities

People

  • Arvo A. Luoma

Organizations

  • Langley Research Center

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aeronautics
  • Air Flow
  • Aircraft Guns
  • Aircrafts
  • Boundary Layer
  • Flow
  • Guns
  • Mach Number
  • Machine Guns
  • Measurement
  • Navy
  • Sea Level
  • Standards
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerospace Engineering
  • Fluid Dynamics.
  • ballistics.