ADMINISTRATIVE
NOTICE
INCH-POUND
MIL-HDBK-1599A
NOTICE 2
5 SEP 2006
DEPARTMENT OF DEFENSE
HANDBOOK
BEARINGS, CONTROL SYSTEM COMPONENTS, AND ASSOCIATED
HARDWARE USED IN THE DESIGN AND CONSTRUCTION OF
AEROSPACE MECHANICAL SYSTEMS AND SUBSYSTEMS
TO ALL HOLDERS OF MIL-HDBK-1599A:
1. THE FOLLOWING PAGE OF MIL-HDBK-1599A, SECTION 601-6 IS INCORRECT AND
NEEDS TO BE DELETED:
3.5.1.1 Material and configuration. The material, configuration, and quality shall conform to MIL-T-8878
and MS21251. Steel turnbuckles are not approved for aircraft use.
3.5.1.2 Usage. The MS21251 aluminum and brass turnbuckles are approved for primary controls, secondary
controls, and auxiliary cable assemblies. The appropriate size turnbuckle shall be used for the applicable size
cable as noted on MS21251.
3.5.1.3 Strength. The MS21251 aluminum and brass turnbuckles shall withstand the minimum breaking
strength of the appropriate size cable. Size selection shall be on this basis.
2. Presently this document contains a requirement that prohibits the use of steel turnbuckles on
aircraft. Recently a galling/chip problem with brass turnbuckles used on aircraft was reported.
This problem was resolved by using steel turnbuckle bodies as specified in MIL-DTL-8878, a
specification developed exclusively for aircraft control applications. Furthermore, MS21251,
which serves as the basic MIL-HDBK-1599 aircraft turnbuckle standard, includes the use of steel
materials. Research into this issue indicates that the reason for establishing this part
of Requirement 601, paragraph 3.5.1.1 was a corrosion problem with the steel bodies.
However, the current specification governing these parts requires the use of cadmium plating on
these parts eliminating the corrosion problems that may have existed back when this requirement
was generated. An administrative change was the best thing to use to correct this Mil Handbook
and a revision is being planned.
3. RETAIN THIS NOTICE AND INSERT BEFORE TABLE OF CONTENTS.
4. Holders of MIL-HDBK-1599A will verify that the above text is deleted from this page
indicated above. This notice page will be retained as a check sheet. This issuance, together with
appended pages, is a separate publication. Each notice is to be retained by stocking points until
the standard is completely revised or canceled.
AMSC N/A FSC 31GP
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