It is said that in war, amateurs devise tactics while professionals plan logistics. America’s status as a virtual island nation makes this doubly true – to even get to theaters of interest, much less conduct useful operations, logistics support is vital. Such innovations as nuclear power do little to change this – fuel for the ship may be unnecessary, but the crew still has to eat, equipment still needs spare parts and embarked aircraft still burn petroleum.
This has undergone many iterations – in the days of sail, ships could travel for months in between stops ashore for food, fresh water and timber. The advent of coal rendered ships’ schedules more dependable but also their cruising ranges more finite, and necessitated the establishment of coaling stations at places far afield for any country that wanted a global presence. Thus, the need for a navy to defend far-flung territories required the procurement of more far-flung territories in order to fuel that very navy. Such is the circular logic of imperialism.
The Royal Navy saw an obvious problem with this. In a maritime conflict, a fleet at sea would rapidly deplete its fuel and need to replenish somewhere. Through a few simple calculations of time, distance, and fuel consumption, an enemy who knew the general location of a British fleet could guess when and where it would need to refuel, and plan its maneuvers accordingly. So as early as 1870, the Royal Navy was already experimenting with ways of transferring coal from colliers to warships underway. In theory, this meant ships could replenish at sea, anywhere.
But coal is bulky, and ships need vast quantities of it. So it didn’t work very well.
The United States Navy took notes and made its own attempts – but what really enabled underway replenishment to work was oil. It’s much easier to pump fluid through a hose than pass boxes back and forth. On April 6, 1917, an American destroyer flotilla headed to the U.K. was successfully refueled off the coast of Greenland by an oiler under the supervision of none other than LCDR Chester Nimitz, the XO and chief engineer. It wasn’t standardized, though, until immediately before World War II, when RADM Nimitz did some further testing from his perch in the Bureau of Navigation.
A lot of things can claim to have won the war in the Pacific – unrestricted submarine warfare, Navajo code talkers, lucky pilots, plucky Marines – but ultimately none of them were possible without logistical backing. A recent post was about how big the ocean is. With an expanse so vast, no campaign or meaningful operation of any kind, could have been sustained without underway replenishment.
Here’s how it’s done.
(A note on the photos: Several are my photos, but I also borrowed a few from Navy public affairs where I didn’t have a suitably demonstrative shot. You will see the point of view of both the receiving and providing ship.)
- Approach from behind and off to the side a bit.
- Gently pull forward so your receiving station is even with the oiler’s chosen fueling station.
- Send over a shotline – i.e. shoot a grenade across with a thin line trailing behind it (which you can actually see in the photo below). The tanker’s crew will literally chase it down and pick it up off the deck.
- The receiving ship will pull that line back, which the providing ship has tied to a cable and a “phone-and-distance” line. It has numbered flags on it so the conning officer has a visual cue for the distance between ships.
- Then it basically becomes a matter of sending progressively bigger lines and cables back and forth until finally you have a spanwire under tension between the two ships. When it’s tensioned, you can send the fuel hose (as seen below). Using another tensioned wire at a different station, you can also send palletized cargo to and fro.
- Pray that the ocean doesn’t look like this (the worst part was we couldn’t get food across… not that we’d have been able to eat much).
- Don’t forget your breakaway song!
Keep in mind the ships are sailing in close proximity on a straight course for two or three hours. If you want to compress three hours down to three minutes, here is a frenetically-paced video for you. It can be nerve-wracking, yet is done with astonishing regularity without incident (most of the time).
Anyone with pretensions of global reach needs to be able to do this. It is not optional.