Accession Number : ADA184443

Title :   Engine/Airframe Response Evaluation of the HH-60A Helicopter Equipped with the T700-GE-701 Transient Droop Improvement Electronic Control Unit.

Descriptive Note : Final rept. 9 Jun-25 Aug 87,

Corporate Author : ARMY AVIATION ENGINEERING FLIGHT ACTIVITY EDWARDS AFB CA

Personal Author(s) : Bender,Gary L ; Adkins,James A ; Lockwood,Roy A

PDF Url : ADA184443

Report Date : Oct 1986

Pagination or Media Count : 79

Abstract : The engine/drive train response was stable for all speed/power turbine speed droop recovery characteristics, and power turbine speed governing characteristics was the HH-60A with the T700-GE-401 engines equipped with the -401 transient droop improvement engine control unit. The HH-60A with the T700-GE-401 engine equipped with the -701 transient droop improvement engine control unit (with and without the collective potentiometer input) exhibited larger rotor speed droop, noticeable drive train oscillation during droop recovery, and less desirable power turbine speed governing characteristics. The undesirable engine/airframe characteristics of the HH-60A with the -701 transient droop improvement engine control unit is a shortcoming. The UH-60A with the T700-GE-700 engine demonstrated the largest main rotor speed droop but residual drive train oscillations were small, droop recovery characteristics were more predictable and power turbine speed governing was noticeably more stable than demonstrated by the T700-GE0-401 engines equipped with the -701 transient droop improvement engine control unit. The undesirable engine/airframe response (large main rotor speed droop) of the UH-60A with the T700-GE-700 engines is a previously identified shortcoming. Future designs for the UH-60 engine control units should include all the transient droop improvements of the -401 transient droop improvement engine control unit. Additionally, future designs of engine control units should have dynamics tailored to the particular helicopter in which the engines are to be installed.

Descriptors :   *HELICOPTERS, *TURBOSHAFT ENGINES, CONTROL SYSTEMS, MODIFICATION, ELECTRONIC EQUIPMENT, FLIGHT MANEUVERS, RESPONSE, PERFORMANCE(ENGINEERING), STABILITY

Subject Categories : Helicopters

Distribution Statement : APPROVED FOR PUBLIC RELEASE