Engineering Flight Test, AH-1G (HueyCobra) Helicopter Autorotational Entry Characteristics

reportActive / Technical Report | Accession Number: AD0887550 | Open PDF

Abstract:

Engineering flight tests were conducted to quantitatively evaluate the response of the AH-1G HueyCobra helicopter to simulated sudden engine failures at high airspeed and high engine power combinations in two configurations. Additionally, simulated engine failures were investigated at 100 knots calibrated airspeed KCAS with the stability and control augmentation system SCAS ON and OFF to determine the differences in aircraft response with an inoperative SCAS. Aircraft response to simulated sudden engine failure was characterized by rapid roll attitude changes and rapid main rotor rpm decay rates, both of which were unacceptable at the maximum engine torque settings. The severity of the aircraft response is primarily a function of engine torque at the time of failure. The AH-1G helicopter fails to comply with both the present and proposed military specifications for flying qualities of helicopters with regard to autorotational entry at high-airspeedhigh-torque conditions.

Author(s):
Buss, Marvin W. ; Nicholson, Brock M.
Author Organization(s):
ARMY AVIATION SYSTEMS TEST ACTIVITY EDWARDS AFB CA
Descriptive Note:
Final rept. 4 Aug 1970-23 Apr 1971
Supplementary Note:
DOI: 10.21236/AD0887550
Pagination:
0061

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Project Number(s):
USAVSCOM-70-25, AVSCOM-70-25
Monitor Series:
USAASTA
 Subject Terms
Joint Capability Areas:
JCA_3_Force Application; JCA_3.1.1_Maneuver to Engage; JCA_3.1_Maneuver; JCA_7.2.1_Mitigate Lethal Effects; JCA_7.2_Mitigate; JCA_7_Protection; JCA_6_Net Centric; JCA_6.1.3_Switching and Routing; JCA_5_Command and Control; JCA_6.1_Information Transport; JCA_4.6_Engineering; JCA_3.2_Engagement; JCA_3.2.1_Kinetic Means; JCA_1_Force Support; JCA_5.3_Planning; JCA_5.4.3_Establish Rule Sets; JCA_5.4_Decide; JCA_1.2.5_Lessons Learned
Communities of Interest:
Air Platforms
Descriptor(s):
*HELICOPTERS, FAILURE, RESPONSE, AUTOROTATION, FAILURE(MECHANICS), TORQUE, HELICOPTER ENGINES, STABILIZATION SYSTEMS, FLIGHT TESTING, AIRSPEED
Field(s)/Group(s):
Helicopters
Keyword(s):
AH 1G AIRCRAFT, HUEY COBRA, H 1 AIRCRAFT, SCAS(STABILITY AND CONTROL AUGMENTATION SYSTEM), STABILITY AND CONTROL AUGMENTATION SYSTEM
Report Date:
1971 Apr 01