MIL-DTL-87218 Cable, Lockclad, For Aircraft ControlThis specification covers the requirements for lockclad control cable material used in aircraft flight controls and aircraft control cable assemblies that include lockclad as a portion of the assembly. Lockclad is defined as the resulting material of swaging aluminum alloy tubing onto MIL-DTL-83420, type I, nonjacketed wire rope to the extent necessary to comply with the elongation and coefficient of thermal expansion properties specified herein.

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MIL-DTL-87218E

4.3.3 Rejection. The failure of any specimen shall be cause for rejection of the lot

represented.

4.4 Test method.

4.4.1 Examination of product.

4.4.1.1 Components. Manufacturer certificates shall be used to determine compliance

with 3.2.1, 3.2.2 and 3.3.2.1 and component QPL requirements. When required, manufacturer

certificates shall be used to determine compliance of the terminals to their requirements

including QPL requirements.

4.4.1.2 Identification and workmanship. Each assembly shall be examined to determine

compliance with 3.5 and 3.6. When required, the examination shall include compliance of the

terminals to their respective detail sheet.

4.4.1.3 Cladding placement. Each assembly shall be examined for compliance with

4.4.2 Breaking strength.

4.4.2.1 Breaking strength test. For lockclad furnished as assemblies with terminals, two

assemblies from each lot of 40 or less assemblies or three assemblies for each lot of 41 to 110

assemblies shall be loaded, by gripping the terminals at each end, in tension to the MBS of the

size and type base wire rope used in the manufacture of lockclad. The MBS is specified in

MIL-DTL-83420. Terminal slippage, broken wires in the bare portions of the base wire rope in

excess of those allowed by MIL-DTL-83420 or MIL-DTL-6117, longitudinal or circumferential

cracking of the cladding, or wire rope breakage, are cause for rejection of the lot. This test shall

comply with all requirements of MIL-DTL-6117. Assemblies used for this test shall be

destroyed.

4.4.2.2 Breaking strength test for qualification. Load each lockclad assembly, by

gripping the terminals, in tension to failure of some component of the assembly. Successful

completion of the test requires that all three assemblies (see 4.2.2) fail in the base wire rope at or

above the MBS for the wire rope.

4.4.3 Elongation. Three lockclad control cable assemblies similar to those manufactured

per 4.3.2.1 shall be manufactured for the qualification test. Specimens shall be gripped at the

terminals and loaded to not more than 1 percent MBS of the base wire rope. The elongation

shall be determined as follows:

Designate and measure a length of not less than one foot of cladding on each assembly.

Gradually increase the tension load to 60 percent MBS of the base wire rope. Measure

the length of the designated section of cladding at not more than each 5 percent MBS

increment. The elongation at the appropriate loads shall be within the elongation values