Fleet Readiness Center Southwest (FRCSW) artisans are responding to a nagging problem affecting many MH-60S multi-mission Sea Hawk helicopters assigned to Helicopter Sea Combat (HSC) squadrons.
Since last September, corrosion and wear to the airframe’s aft floorboards have interfered with the ability to install auxiliary fuel tanks needed for longer flights.
To date, 53 floorboards have been identified.
“This has to do with the way the Extended Range Fuel Systems (ERFS) fuel tank is mounted on the aft floorboard,” said Andrew Crump, FRCSW planner and estimator (P&E). “If the floorboard is significantly corroded in the area that the ERFS tied-down points are, then the floor board is down for the ERFS.”
“The Fleet Support Team (FST) received a new fatigue analysis from the OEM that placed extremely conservative damage limits on the floorboards to comply with the 20-20-10 crash-load requirements,” said HSC Wing Pacific (HSCWINGPAC) Maintenance Officer Cmdr. Rex Puentespina.
“Compounding the problem is that the supply system does not have the aft floorboards in stock, and the estimated deliveries are well into 2021.”
To address the issue, the FST developed depot-level repair procedures to the floorboards until the new ones arrive. In early August, FRCSW established an in-service repair (ISR) on the floorboards, and moved them to Building 325 where the repair process began.
They are currently undergoing repair analysis, though not all of them may qualify. One or two artisans, P&E and FST personnel will work on each repair.
The first step in the repair process is the removal of corrosion. Afterward, FST will determine if enough material remains of the floorboard to justify continuing the procedure. Artisans will apply a corrosion-prevention compound to those floorboards that pass FST evaluation.
Finally, installation of a doubler and shim will be used to allow the ERFS placement.
Initial repair time was estimated at three or four days using available materials, but Puentespina noted that because these are the first repairs to the floorboards and that the methods and evaluations are still evolving, it has yet to be determined exactly how long the procedure will take.
“HSCWINGPAC appreciates the support, partnership, and efforts by FRCSW in helping with the HSC community issue. The assistance provided via the repairs enables continued mission readiness for all HSCWP squadrons,” he said.