Government auditors in Washington have criticised a plan by the US Coast Guard (USCG) to consolidate the service’s rotary-wing aviation fleet to a single helicopter type.

The independent US Government Accountability Office (GAO) on 9 April said the USCG has “not fully assessed whether this transition would result in the quantity of helicopters it needs”.

Under a $57.9 billion aviation modernisation initiative, the Coast Guard plans to eliminate its fleet of short-range Airbus Helicopters MH-65D/E Dolphin search and rescue helicopters, 98 of which are currently in service.

Instead, the USCG will transition to an all medium-range fleet, adding aircraft in that category. The hybrid service – which performs military and law enforcement missions – presently operates 48 Sikorsky MH-60T Jayhawks as its medium-range search and rescue platform.

The modernisation plan calls for a total rotary aviation fleet of at least 127 MH-60Ts, consolidating to a single helicopter type.

US Coast Guard MH-60T rescue swimmer c USCG

Source: US Coast Guard

The US Coast Guard wants to restructure its helicopter fleet so it is entirely based on the Sikorsky MH-60T Jayhawk, a medium-range, maritime search and rescue platform

Coastguard leaders in 2021 made the decision to eventually sunset the MH-65, citing increased difficulty in obtaining critical parts for the type after production of the H155, on which it is largely based, ended in 2018.

The 9 April GAO report notes shortages of components such as gearboxes have led to decreased aircraft availability and caused an overall reduction in flight hours for the MH-65 fleet.

Notably, the USCG restructuring plan would result in fewer total aircraft – 127, compared with the current count of 146 helicopters in the mixed MH-65/MH-60T composition.

First MH-60T replacement airframe

Source: Sikorsky

Sikorsky is currently delivering replacement MH-60T hulls, which will extend the service life of existing aircraft

This represents a 13% reduction in fleet size – for a service tasked with patrolling some 94,000 miles (153,000km) of coastline, including search and rescue, drug interdiction and migrant interdiction missions.

The 127 aircraft count will be achieved by refurbishing existing Jayhawks with new hulls from Sikorsky and converting used H-60-family aircraft from the US Navy.

Sikorsky began delivering replacement MH-60T airframes to the USCG in November 2023. The 10-year programme will extend the service life of 45 existing aircraft into the 2040s.

Each airframe consists of nose, cabin and aft transition structures combined as a single assembly, according to Sikorsky.

Officials with the USCG argue the constraints of a smaller rotorcraft fleet will be offset by the Jayhawk’s improved performance compared with the Dolphin.

“The Coast Guard reports it would have a more capable helicopter fleet, as the MH-60T helicopter has about double the range as the MH-65D/E,” the GAO notes.

However, auditors at the watchdog appear sceptical of the argument that better range can make up for 19 fewer aircraft.

“The Coast Guard has not assessed whether the MH-60T helicopter best meets its mission needs under its plans to consolidate its fleet,” the GAO says.

The report further notes that the USCG did not assess any alternative fleet options that could be used to support the consolidation decision.

US Coast Guard MH-65 c USCG

Source: US Coast Guard

The US Coast Guard currently operates 98 MH-65D/E Dolphins, a short-range type produced by Airbus Helicopters

A 2020 study by the Rand Corporation, a US-based policy research institute, supported the coast guard maintaining a mixed fleet of short- and long-range helicopters.

That study found a fleet primarily based on the MH-60T, but supplemented by a short-range option, would be of most benefit to the USCG’s diverse operational responsibilities.

Drug interdiction appears to be an area of particular concern. The GAO notes these operations often take place in far offshore or remote locations, making use of MH-65D/Es stationed onboard cutter ships.

“Currently, the MH-65D/E helicopter is the only Coast Guard helicopter that is fully compatible for cutter-based deployments,” the GAO says.

“The MH-60T helicopter is heavier and larger, and thus requires additional equipment to make it compatible with the cutter for deployment,” the report adds.

MH-65 on USCGC Stone c USCG

Source: US Coast Guard

Government auditors say the MH-65D/E Dolphin is uniquely suited for supporting far offshore USCG missions, particularly drug interdiction

While the USCG is acquiring hardware and developing procedures to support Jayhawk deployments on certain cutters, the GAO says the service failed to formally evaluate whether the MH-60T is the best platform for such a role.

“It is unclear if the MH-60T helicopter is best-suited to serve all the Coast Guard missions and associated operations,” the GAO concludes.

In the near-term, the MH-65 will continue active service with the USCG.

The service in 2020 launched a programme to upgrade D-variant Dolphins to the latest E-standard configuration, which brings a modernised flight-control system, digital cockpit display and upgraded weather radar.

All 98 of the coast guard’s MH-65s are expected to finish E-standard upgrades later this year. A separate service life extension programme increased the operating life of each aircraft by 10,000 flight hours, to a total of 30,000h.

Fiscal year 2024 budget documents indicate the USCG plans to decommission six of the rotorcraft.