“Multiple Design Deficiencies” Will Delay CH-53K Testing, Entry to Service

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February 25, 2019 | Originally published by Date Line: February 25 on

Multiple design deficiencies found during post-delivery testing of the Sikorsky CH-53K King Stallion will delay operational testing and entry to service with the Marine Corps until at least 2021, according to the U.S. Defense Department Director of Test and Evaluation’s annual report.

A planned initial operational capability (IOC) declaration in December 2019 “will be delayed” and the CH-53K program office is “working a major schedule revision” to address a list of structural problems found during system development and demonstration, according to the DOT&E report published Jan. 31.

“The Program Office is requesting additional funding to complete sufficient developmental testing to enter [initial operational testing and evaluation] with a [key performance parameter] compliant system,” the report says. “Technical problems have extended [System Development and Demonstration] well beyond original projections.”

IOT&E is now projected to start in early 2021 so “multiple design deficiencies discovered during early testing” can be corrected, according to the report. The deficiencies include airspeed indication anomalies, low reliability of the main rotor gearbox, hot gas impingement on aircraft structures, tail boom and tail rotor structural problems, overheating of main rotor dampers, fuel system anomalies, high temperatures in the number-two engine bay and hot gas ingestion by the number-two engine, which could reduce available power.


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