Accession Number : AD0830120

Title :   ENGINEERING FLIGHT TEST OF THE AH-1G HELICOPTER EQUIPPED WITH THE XM-20 ARMAMENT SUBSYSTEM (AUTOMATIC 20MM CANNON).

Descriptive Note : Letter rept.,

Corporate Author : ARMY AVIATION SYSTEMS TEST ACTIVITY EDWARDS AFB CA

Personal Author(s) : Dorris, Stephen G. ; Hall, Gary C.

Report Date : MAR 1968

Pagination or Media Count : 30

Abstract : The engineering flight test of the AH-1G helicopter equipped with the XM-20 armament subsystem (automatic 20MM cannon) was conducted at Fort Hood, Texas from 31 January 1968 through 2 February 1968 by the US Army Aviation Test Activity, Edwards Air Force Base, California. Firing and nonfiring flight tests were conducted to determine the effects on the stability and control characteristics of the AH-1G helicopter caused by installation of the XM-20 armament subsystem. These tests were primarily qualitative in nature with limited qualitative data. The only stability and control characteristic which was affected either in the firing or nonfiring mode was the static longitudinal cyclic position gradients which were low at high speeds. The deficiencies detected during this test were the interference of the XM-20 gearbox with the XM-159 rocket pod and unreliability of the standard airspeed system due to the location of the static port in proximity to the XM-20 blast pressures. One firing rate of 600-800 spm is considered optimum. The XM-20 appears to offer greater stand-off capability, greater accuracy and more killing power than 2.75 inch rockets. It appears to be a reliable subsystem. The XM-20 configuration should be finalized, installed on a production AH-1G helicopter and certified for airworthiness throughout the AH-1G flight envelope as soon as possible to allow early introduction to Republic of Vietnam. (Author)

Descriptors :   (*HELICOPTERS, WEAPONS), (*AIRCRAFT GUNS, HELICOPTERS), AUTOMATIC WEAPONS, FIRING TESTS(ORDNANCE), EXTERNAL STORES, COMPATIBILITY, STABILITY, MANEUVERABILITY, VIBRATION, LEVEL FLIGHT, VIETNAM, ARMY AIRCRAFT, HOVERING, ROCKETS, AIRCRAFT FIRE CONTROL SYSTEMS.

Subject Categories : Helicopters
      Guns

Distribution Statement : APPROVED FOR PUBLIC RELEASE