Accession Number : AD0681244
Title : IMPROVED CONCEPT OF ELASTOMERIC BEARINGS FOR UH-1 TAIL ROTOR ASSEMBLY
Descriptive Note : Final technical rept.
Corporate Author : BELL HELICOPTER TEXTRON INC FORT WORTH TX
Personal Author(s) : Fagan, C H
PDF Url : AD0681244
Report Date : Oct 1968
Pagination or Media Count : 62
Abstract : This report presents the results of a research program to extend the state of the art of elastomeric bearings and to investigate further their application on a UH-1 tail rotor. In a previous program (See AD-661 614), Teflon journal bearings were used in conjunction with an elastomeric thrust bearing for carrying the edgewise and flapwise bending moments and for stiffness control. For the subject investigation, the Teflon journal bearings were eliminated. One radial and two thrust bearings were designed and fabricated for the blade grip application. One thrust bearing employed chevron shaped separators, and the other used 45-degree dished sheets between the layers of elastomer. Bench tests were conducted, and two blade grip bearing arrangements were whirl tested. One arrangement used a single chevron thrust bearing, and the second used the 45-degree dished thrust bearing in conjunction with the radial bearing. The tests showed acceptable frequency placement for the radial- thrust bearing arrangement. The chevron arrangement frequency placement was unsatisfactory. Flight tests of the radial-thrust bearing arrangement showed acceptable blade and hub structural loads, which were in most cases comparable to those of the UH-1.
Descriptors : *TAIL HELICOPTER ROTORS, *THRUST BEARINGS, COMPOSITE MATERIALS, COMPRESSIVE PROPERTIES, DEFLECTION, ELASTOMERS, HALOCARBON PLASTICS, HELICOPTERS, LOADS(FORCES), RESONANT FREQUENCY, SHEAR STRESSES, VIBRATION
Subject Categories : Helicopters
Machinery and Tools
Distribution Statement : APPROVED FOR PUBLIC RELEASE