Accession Number:

ADA160862

Title:

Preliminary Airworthiness Evaluation of the AH-1S (Modernized Cobra) with the HELLFIRE, TOW, and Stinger Missiles Installed

Descriptive Note:

Final rept. 17 May-27 Jul 1984

Corporate Author:

ARMY AVIATION ENGINEERING FLIGHT ACTIVITY EDWARDS AFB CA

Report Date:

1984-10-01

Pagination or Media Count:

193.0

Abstract:

The aircraft was operated at gross weights up to 10,400 lb, up to 11, 340 feet density altitude and at a lateral center of gravity cg range from one inch right to approximately three inches left. The asymmetric loadings were caused by the various combinations of armament configurations. The change in equivalent flat plate area compared to the clean aircraft for each configuration varied as a function of airspeed. At 130 knots true airspeed KTAS, the increased flat plate area was 4.2 square feet for the Launcher configuration, 4. 8 square feet for the TOW configuration, 6.6 square feet for the Hellfire and HellfireTOW configurations, and 7.8 square feet for the StingerHellfireTOW configuration. The increase in flat plate area for the StingerHellfireTOW configuration reduced maximum level flight speed for normal rated power by approximatley 8 KTAS. With the exception of the two armament related shortcomings listed below, the handling qualities and the reactions to system failures of the AH-1S MC were not significantly changed by the asymmetric loading of the various armament configurations. Four shortcomings were noted and follow in decreasing order of importance 1 the high left rolling response to a sudden engine failure at power settings above 75 torque 2 the undesirable maneuvering stability characteristics above 1.4 gs 3 insufficient left pedal margin available in right sideward flight above 10 knots in the Hellfire and HellfireTOW configurations and 4 insufficient left pedal margin available for ball-centered forward flight below 30 KCAS in the armament configurations with left lateral cf offset. A CAUTION is recommended for inclusion in the operators manual dealing with.

Subject Categories:

  • Helicopters

Distribution Statement:

APPROVED FOR PUBLIC RELEASE