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Original Date: 08/10/1998
Revision Date: 01/18/2007
Information : Cross Deck Pendants
High speed fly-in and recovery of fixed wing aircraft aboard an aircraft carrier is accomplished via an arresting engine. The connectivity between the aircraft and the arresting engine requires a specially designed tailhook, attached to the aircraft frame, to engage one of several cross deck pendants (arresting wires) on the aircraft carrier’s deck. Cross deck pendants must endure extreme stress during fly-ins, and withstand a highly corrosive environment of sea water and sulphur dioxide from the exhaust of ships and aircraft. A failure of an arresting wire or its attached fittings would produce a catastrophic accident, resulting in the loss of a multi-million dollar aircraft, the high risk of death or severe injury to the pilot and crew, and the endangerment of sailors on the deck of the aircraft carrier.
The Naval Air Warfare Center (NAWC), Lakehurst is the only facility in the world that manufactures and assembles cross deck pendants for the Navy. The following steps outline the quality assurance (QA) process:
Certification of Wire
100% batch lot sampled and deadload tested
Eight-foot sample tensile tested to breaking point for each reel
Data recorded and maintained
Certification of Die Material for Press
Material is best that industry has to offer, carpenter 11, grade A
Milling performed on outside dimensions
Clamp blocks together to bore barrel
Heat treat
Magnetic particle inspect
Hand grind to finished dimensions
Magnetic particle inspect
When dies are changed in the process, another eight-foot sample tensile test is performed
Certification of Terminals
Manufacture from raw material 4130
Composite of raw material to ensure proper heat code is analyzed by Materials Branch
Dimensionally inspect terminals
At several places during the process, check terminal hardness. Must be Rockwell C and 100% check on every cable
Magnetic particle inspect entire terminal
Ultrasonic test eye hole and 100% check
Certification of Swaged Cable
Verify deadload and tensile test results of cable reel to be utilized
For each reel utilized, another eight-foot sample is manufactured and tested
Wire is cut and metal tags are placed on each wire to mark the reel number and manufacturer
10% of swaged assemblies from each reel are proofloaded
Measure diameter of cable so inner dimension of terminal has interference fit between 0.00 and 0.016 inch
Terminals are etched with hit number which records operator, reel used, press used, and heat code of terminal
Cables are prepositioned and inspection hole is checked
Cables are swaged
Measurements of strand gap spacing checked
Magnetic particle inspect entire terminal
Ultrasonic test entire barrel
Test Data
All data is reviewed, certified, logged, and then shipped with the cable
These steps ensure that every cross deck pendant manufactured at NAWC, Lakehurst is of the highest quality. Quality is imperative because the safety factor of the wire rope is limited to 1.14 of the requirements. Otherwise, the arresting wire’s mass would adversely affect the fatigue life of the aircraft. NAWC, Lakehurst’s skilled artisans have acquired years of experience in this QA process, and no aircraft losses can be attributed to the failure of more than 95,000 cross deck pendants manufactured to date.
For more information see the
Point of Contact for this survey.
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