MIL-F-18372(Aer)
Cable Load in % Specified
Cable Breaking Strength
Sheave Ratio
1
10
10
20
20
28
Cables shall not be subjected to critical bends at the junction with cable terminals or other
attaching points such as drums, horns, etc.
3.1.1.17.8 Cable Alignment - Cables shall not be misaligned with sheaves in excess of the following
values: (The alignment of a cable with its pulley is defined as the angle between the center line of
the cable and the plane of the pulley.)
(a) Primary flight controls - Not over 10, except where AN219, AN220, or AN221 pulleys are
used, or where side travel of the cable exists, and then not over 20.
(b) All other controls - Not over 20, except where AN219, AN220, or AN221 pulleys are used, or
where side travel of the cable exists, and then not over 3°.
3.1.1.17.9 Turnbuckles - Turnbuckle terminals shalll not have more than three (3) threads exposed at
either end. All turnbuckle assemblies shall be properly safetied.
3.1.1.17.10 Take-Up Links - Vernier links shall be provided, where necessary, to facilitate proper
rigging of the cable systems.
3.1.1.17.11 Pulleys and Sheaves - Pulleys shall be of adequate capacity and diameter for the size of
cables and loads. Anti-friction baring pulleys shall be used in all flight controls.
3.1.1.17.12 Drums, Sectors, and Quadrants - All cables shall be positively attached to driven or
driving drums, sectors, etc. Drum, sectors, or quadrants shall have at least 100 wrap of the the driving
cable after the limits of its range of movement in both directions have been reached.
3.1.1.17.13 Guards - Guards shall be installed at all sheaves (pulleys, sectors, etc.,) to prevent
the cable from jumping out of the groove of the sheave. Guards shall be installed at the approximate
point of tangency of the cable to the sheave and where the cable wrap exceeds 90°, one or more inter-
mediate guards shall be Installed. To prevent binding of the of the sheave due to relative deflections in
the airplane structure, all guards shall be supported by the supporting brackets of the parts which
they guard. Additional guards shall be installed on sectors at the point of entry of the cable into
the groove from its attachment. The design of the rubbing edges and selection of materials shall be
such as to minimize cable wear and prevent jamming, even when the cable is slack.
3.1.1.17.14 Fairleads - Fairleads shall be used wherever necessary to keep cables from chafing and
slapping against parts of the aircraft. Fairleads shall not cause any angular change in the cable.
They shall be of non-hygroscopic, non-abrasive material. Fairleads shall be split to permit easy
removal, unless the hole in the fairlead is of sufficient size to permit the cable with the swaged
terminals attached to be threaded through. Where space permits the fairleads should clear the primary
flight control cables by a minimum of ¼. The cables may rest against the lower edge of the hole in
the fairleads on long straight runs where the cable would nornally sag due to their own weight even
when properly rigged.
3.1.1.17.15 Clearance - All control cables shall have a minimum of ½" inch clearance with all wiring,
tubing, and removable equipment (exclusive of the basic airframe structurre). Clearances of less than
½" are permitted between the cables and the basic airframe structure provided suitable fairleads are
installed.
3.1.1.18 Push-Pull Systems
3.1.1.18.1 Adjustable Terminals - Adjustable terminals shall be arranged so that there will be no
possibility of a terminal becoming inadvertently detached. Adjustment shall be possible at one end
only for any single tube. Where one adjustable rod end is made fixed as a means of preventing the rod
from becoming detached, rivets or bolts through the threaded shank shall not be used with threaded ends
6
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business