NTSB: Improper torquing led to destruction of OSV engine


The following is a marine accident brief from the National Transportation Safety Board (NTSB):

(WASHINGTON) — About 1544 local time on Dec. 13, 2017, the offshore supply vessel Red Dawn was transiting through the North Pacific Ocean en route to resupply the radar station Sea-Based X-Band Radar (SBX-1). When the vessel was about 375 miles south-southwest of Amchitka Island, Alaska, its No. 2 main diesel engine suffered a mechanical failure that led to the ejection of components from the cylinder block, consequently destroying the engine. No pollution or injuries to the 12 crewmembers and 33 passengers on board were reported. The estimated damage to Red Dawn totaled $957,000.

Probable cause

‚ÄčThe National Transportation Safety Board determines that the probable cause of the mechanical failure on board offshore supply vessel Red Dawn was a connecting rod assembly on the No. 2 diesel engine that came loose and separated from the crankshaft due to improper tightening (torquing) of the connecting rod bolts during the previous engine overhaul.

Click here to read the report.

By Professional Mariner Staff