Underway Replenishment – How the Navy Fuels Its Fleet

navy refuellingA number of factors play a role in the effective accomplishment of missions – this is especially true for the Navy. With large fleets stationed in different parts of the world, there may be occasions when fuel supplies are difficult to come by.

To counter such problems, the Navy has Military Sealift Command ships which are fully equipped with provisions, fuel, ammunition and spare parts. These ships are sent out to support their comrades and fleet units.

Role of refuelling tankers

Refuelling tankers like those from Mini-Tankers play a crucial role in every mission. Two methods are commonly used – CONREP which indicates connected replenishment and VERTREP – vertical replenishment. They can be used at the same time or not.

In the instance of CONREP, two ships sail side by side and hoses are used to transfer fuel. VERTREP missions use helicopters to do the work. Depending on the circumstances, VERTREP can be done with close proximity or from a distance. This is decided by the amount of cargo to be unloaded.

There are many reasons for favouring refuelling and replenishment with the ships next to each other. First off, this makes it easy for the oiler/replenishment ship to service two ships at the same time. When ships are next to each other, the formation can maintain a steady speed. Thirdly, replenishing side by side helps to get fuel and other essentials to the ship in need all at once. In VERTREP, only fuel can be transferred efficiently. Newer and better replenishment techniques are being developed all the time and this is facilitated by new equipment and systems.

Replenishing cargo and fuel at sea requires planning and a set amount of time. The captains of both ships can initiate emergency breakaway processes if there is any problem – weather related or otherwise.