PACIFIC OCEAN -The Military Sealift Command hospital ship USNS Mercy (T-AH 19) completed MERCEX (Mercy Exercise) 02-15, Jan. 12.

The quarterly exercise is designed to train and integrate approximately 250 Sailors into the full-time crew of approximately 65 Navy personnel and 20 merchant mariners.

Merchant Marine Captain Thomas Giudice, the ship’s master, said these exercises are critical to keeping Mercy ready to deploy on short notice.

“At any moment I could get a message tasking us to get underway for a mission,” said Giudice. “From the moment I get that message, I have five days to get the ship away from the pier and out to sea, fully operational. To make our training the most beneficial, it’s important we do this exercise underway.”

During the weeklong MERCEX, the crew tested shipboard equipment and practiced medical drills in order to make sure their Sailors and merchant mariners were ready to operate the ship and the military treatment facility (MTF) should the order come to deploy.

“This MERCEX provides us an opportunity to do our jobs within the stresses of an operational environment at sea,” said Capt. Melanie Merrick, commanding officer of the military treatment facility aboard Mercy. “We are constantly refining our mission critical training plan, and this exercise allows us to see what we do well when we come together and where we still need to focus more of our efforts to be fully proficient in all of our skill sets.”

Mercy is one of two hospital ships owned and operated by Military Sealift Command that stand ready to provide emergency, on-site care for U.S. combatant forces deployed in operational environments. The hospital ship’s secondary mission is to provide full hospital services to support disaster relief and humanitarian operations worldwide.

With 12 operating rooms and a 1,000-bed capacity for patient care, Mercy and its sister ship USNS Comfort (T-AH 20) are a unique blend of civilian mariners (CIVMARs) and active duty Navy personnel. The merchant mariners are responsible for navigating and maintaining the ship’s engineering plant, what on a traditional Navy ship would be deck, navigation and engineering department’s responsibility. For logistics and supply, the CIVMARs and Sailors divide the workload of making sure they have food, medical supplies, and the complete inventory of items and services a ship and MTF need to operate at sea.

Sailors run almost everything else - the medical treatment facility, flight operations, administration and personnel, communications and operations. However, until the ship is tasked with a mission or exercise, only a minimal contingent of Sailors and merchant mariners remain aboard to handle the ship’s daily requirements.

The ship essentially has three crews - a full-time crew of 20 merchant mariners and 65 Sailors to keep the ship maintained and ready to get underway. A critical core crew brings an additional five merchant mariners and 250 Sailors. The critical core crew's job is to ensure the ship is ready to conduct the full range of operations from an equipment and supply standpoint. The full crew is comprised of 65 merchant marines and approximately 1,100 Sailors, most of which are Navy medical personnel. This full complement allows the ship to deploy worldwide and bring the military treatment facility up to full operational status.

During this MERCEX, the ship integrated and trained its critical core crew, made up of Navy corpsmen, aviation boatswain’s mates, ship’s servicemen, logistic specialists, machinist’s mates and doctors and nurses with various medical specialties.

“If you compare this to a typical Navy ship, MERCEX is like getting 250 new check-ins in one day, and we have to make sure they have everything they need to be successful,” said Command Senior Chief Dedrick Walker, the command senior chief of the military treatment facility aboard Mercy. “They have to quickly integrate into the crew, learn the ship and the MTF. It’s challenging, but it’s a unique opportunity to execute an important mission.”

Many of Mercy’s critical crew come from Naval Medical Center San Diego, and for most of them this was their first time underway.

“MERCEX has been a great opportunity to get our critical crew on board to let them see how to operate at sea,” said Hospital Corpsman 2nd Class CharlesIan Idos. “It’s much different when you have to do your job when the ship is rocking back and forth. If you haven’t done it before, it takes some getting used to, especially in a medical environment.”

Upon completion of MERCEX, the ship will enter into a regularly scheduled maintenance period.