WASHINGTON — U.S. Transportation Command announced this week the largest simultaneous activation of sealift vessels in its history, a stress test of the aging logistics fleet that would be called upon to move up to 90 percent of Army and Marine Corps equipment in the event of a major conflict.

The bulk of the ships activated are the Ready Reserve Force. That group of 46 ships is permanently kept in a reduced operating status, to be activated on short notice. The Maritime Administration has repeatedly warned that the ships are aging and difficult to man due to obsolete equipment.

In total, 22 of the 28 ships activated for the exercise are from the Ready Reserve Force, which is about 48 percent of the fleet. Crewing those ships has been an increasing challenge in recent years due in part to the requirements on mariners to maintain licenses to operate steam-powered ships, which have all but disappeared from the commercial sector.

“In the past they’ve been able to rob the other ships to sort of fill out those numbers,” said Sal Mercogliano, a former mariner and maritime historian at Campbell University. “They’re not going to be able to do that activating 28 ships at the same time … this is going to be a true stress test of the system, both on the maintenance of the vessels and the crewing of the vessels.”

Here’s a list of all 28 of the ships that TRANSCOM activated for the exercise, displacing more than 1.25 million tons, according to Maritime Administration and Military Sealift Command fact sheets.

The SS Curtiss arrives at Port Hueneme to support exercise Pacific Blitz 19. (Cpl. Jacob A. Farbo/U.S. Marine Corps)
The SS Curtiss arrives at Port Hueneme to support exercise Pacific Blitz 19. (Cpl. Jacob A. Farbo/U.S. Marine Corps)

Military Sealift Command

Maritime pre-positioning ships, used to forward-deploy Army stores and gear for use in a crisis. The roll-on/roll-off ships transport cargo vehicles:

  • USNS Benavidez, large medium-speed roll-on/roll-off from Norfolk, Virginia, displacing 62,644 tons.
  • USNS Fisher, large medium-speed RO/RO from Bremerton, Washington, displacing 62,644 tons.
  • USNS Gilliland, large medium-speed RO/RO from Baltimore, Maryland, displacing 62,644 tons.
  • USNS Mendonca, large medium-speed RO/RO from Norfolk, Virginia, displacing 62,644 tons.

Container and RO/RO ships haul containerized equipment and stores, and can accommodate vehicles:

Ready Reserve Force

Fast sealift ships

  • SS Bellatrix, a high-speed vehicle and cargo ship that tops out at 33 knots out of Marrero, Louisiana, displacing 54,895 tons.
  • SS Capella, a high-speed vehicle and cargo ship that tops out at 33 knots out of San Francisco, California, displacing 54,895 tons.
  • SS Regulus, a high-speed vehicle and cargo ship that tops out at 33 knots out of Beaumont, Texas, displacing 54,895 tons

Heavy-lift ships

  • SS Cape Mohican, a heavy-lift barge carrier out of Oakland, California, displacing 57,290 tons.

Crane ships

  • SS Cornhusker State, a crane ship used for lifting heavy loads and for off-shore construction out of Newport News, Virginia, displacing 26,670 tons.
  • SS Grand Canyon State, a crane ship used for lifting heavy loads and for off-shore construction out of Alameda, California, displacing 26,670 tons.

Aviation logistics support ships

  • SS Curtiss, an aviation maintenance support ship out of San Diego, California, displacing 27,980 tons.

RO/RO ships

  • GTS MV Admiral W. M. Callaghan, RO/RO and lift-on/lift-off container ship out of Alameda, California, displacing 26,537 tons.
  • SS Cape Island, RO/RO out of Tacoma, Washington, displacing 36,027 tons.
  • SS Cape Inscription, RO/RO out of Long Beach, California, displacing 36,027 tons.
  • MV Cape Decision, RO/RO out of Charleston, South Carolina, displacing 34,617 tons.
  • MV Cape Douglas, RO/RO out of Charleston, South Carolina, displacing 34,617 tons.
  • MV Cape Ducato, RO/RO out of Charleston, South Carolina, displacing 34,617 tons.
  • MV Cape Edmont, RO/RO out of Charleston, South Carolina, displacing 34,617 tons.
  • MV Cape Kennedy, RO/RO out of New Orleans, Louisiana, displacing 44,466 tons.
  • MV Cape Knox, RO/RO out of New Orleans, Louisiana, displacing 44,466 tons.
  • MV Cape Ray, RO/RO out of Portsmouth, Virginia, displacing 35,369 tons.
  • MV Cape Race, RO/RO out of Portsmouth, Virginia, displacing 35,369 tons.
  • MV Cape Texas, RO/RO out of Beaumont, Texas, displacing 46,868 tons.
  • MV Cape Trinity, RO/RO out of Beaumont, Texas, displacing 46,868 tons.
  • MV Cape Washington, RO/RO out of Baltimore, Maryland, displacing 53,500 tons.
  • MV Cape Wrath, RO/RO out of Baltimore, Maryland, displacing 53,500 tons.