18 Photos That Show The Intensity Of Keeping Warships Supplied At Sea

“UNREP” (short for “underway replenishment”) is the term used to describe the transfer of fuel, food, ammunition, repair or replacement parts, people and mail from supply ships to combatants like frigates, destroyers, and aircraft carriers.

Simply put, UNREP keeps Navy ships at sea. It’s a dangerous and intense evolution.

UNREP begins by raising the Romeo flag. On the control ship, it means, “I am ready for your approach.” On the approaching ship, it means, “I am commencing.”

sea rep romeo flag

Photo: US Navy

One of the most challenging aspects of UNREP is matching the speed of the control ship and steering into position.

steering the ship during replenishment at sea

Photo: US Navy

Once the ships are on a parallel course, a shotline is sent for the phone and distance (P&D) line, which is marked by flags every 20 feet. Once the shotline is fired, sailors on the supply ship catch it like a wedding bouquet.

sea rep shot line with flags

Photo: US Navy

After the shotline is received, line handlers must haul in the messenger line, which is much heavier.

sea rep line pull teamwork

Photo: US Navy

After the wires and hoses are connected, the teams on deck and in the pump room are ready to begin the transfer of cargo and fuel.

sea refueling

Photo: US Navy

Sailors in the pump room monitor fuel levels…

sea rep fuel level monitoring

Photo: US Navy

… while pallets of food, mail, and supplies are transferred topside.

palet transfer sea rep

Photo: US Navy

At the same time sailors man the .50 cals, ever-vigilant for threats.

standing watch during sea rep

Photo: US Navy

Thousands of pounds of fuel and cargo are transferred between the ships while maintaining the same speed and distance apart.

side-by-side ships during sea rep

Photo: US Navy

The exchange can be dangerous for both sides…

sea rep big splash

Photo: US Navy

Sailors have to watch out for rogue waves.

sea rep hangar bay wave

Photo: US Navy

Helicopters can also be used for resupply …

preparing for vert rep

Photo: US Navy

They call this process “VERTREP,” short for “vertical replenishment.”

vert rep fork lift transport

Photo: US Navy

Resupplying the ship is an all-hands task. In this photo, sailors and Marines on an amphibious ship form a human chain to transfer packages.

supply chain sea rep

Photo: US Navy

Sometimes ships will tag-team a supply ship to save time. In this photo, two missile destroyers — an Arleigh Burke class and a Ticonderoga class — are attached to the USNS Lenthall (T-AO 189).

tag team sea rep

Photo: US Navy

Sometimes an UNREP could go well into evening…

night time sea rep

Photo: US Navy

… and package distribution could go on for hours after the ships have disconnected.

sea rep hangar bay boxes

Photo: US Navy

But, the long hours and hard work pay off when you receive a care package from home; it’s like Christmas.

sea rep santa clause

Photo: US Navy