Clash of The Carriers

Though methods had existed for passing coal from one ship to another, unreps became more common after World War I, when navies changed to fuel oil. There were two basic methods for transferring fuel while under way: rigging lines bow to stern or side by side, known as “riding abeam.” The latter became standard.

The oiler and its “customer” steamed alongside each other, usually at eight to twelve knots. One or both ships deployed bumpers or “fenders” of heavy manila hemp to protect the hulls in the event of collision.

With forward motion stabilized, “messenger” or “pilot” lines were propelled across the fifty feet or so separating the two ships. Sailors secured the ropes, which became the means of passing “distance lines” heavy enough to support the fuel hoses under pressure. Once the distance lines were in place, the oiler crew rigged out the booms holding the fuel lines, which were then hauled across the expanse separating the two ships. With the hoses secured in receptacles leading to the recipient’s fuel tanks, the oiler then began pumping thousands of gallons of Bunker C.

However, even in ideal conditions it was almost impossible for two ships to maintain an even strain on the lines. A twenty-five-thousand-ton oiler fueling a ten-thousand-ton cruiser imparted a good deal of inertia from normal movement through the water. In moderate wind or tossing seas, lines alternately went taut or slack, requiring power winches to adjust line tension. Sometimes gangs of sailors had to compensate by muscle power. It was especially difficult for the oiler crews, who often worked on exposed well decks with low freeboards. They grew accustomed to being drenched as Pacific swells whipped up saltwater crests that cascaded onto the deck and swirled calf-high around them.

Inevitably, there were errors. Suspension lines sometimes parted, which complicated the process, but four-inch fuel hoses also could snap under violent strain. In that case, there was nothing to do but shut off the pumps to prevent loss of additional bunker fuel into the sea. But by and large, the complex evolution was accomplished so often that it became routine.

Because oilers could not always operate with the combatant units, large men-of-war also had the ability to pump Bunker C. Battleships and fleet carriers frequently fed the precious fuel to cruisers and destroyers, using largely the same techniques as the dedicated tankers. The ability of battlewagons and flattops to top off the “smallboys” was doubly beneficial, as it permitted independent operations for two or three days at a time, until a tanker rendezvous could be arranged.

One of the major unrep innovations was attributed to Captain Duke Hedding, who became Mitscher’s operations officer. While serving as chief of staff to Rear Admiral Charles Pownall in 1943, Hedding thought he saw a better way to perform underway replenishment. During the Gilbert Islands operation in November, the decision already had been made to refuel the entire fleet at sea rather than rotate task groups back to the New Hebrides, a thousand miles and five days out of the way.

Previously, the operating technique required the oiler to approach the carrier. During the Tarawa landings, Hedding watched a tanker linked to a cruiser make an approach to a carrier. The procedure struck him as silly. The aviator remarked to his boss, “We all know how to fly formation. Let’s set the tanker up there and let everybody come up and make an approach on the tanker and just run the fuel lines across.” Pownall thought a moment, then replied, “Let’s try it.”

Duke Hedding’s idea worked. Dispensing with the prewar method of rigging breast or spring lines, oilers and recipients alike learned that they could conduct unreps without heading into the wind.

After the war, officers of the U.S. Strategic Bombing Survey (Pacific) questioned Japanese strategists about the reasons for America’s victory. Apart from the obvious industrial disparity, ranking high on the list was the ability to keep task forces at sea for weeks at a time. That meant oilers. If the American public had little idea of their contribution, the warlords in Tokyo fully knew their worth.

Among the hundreds of ships that departed the Marshalls on June 6 was a particular auxiliary vessel, a noncombatant. Though she carried four five-inch, .38-caliber guns plus eight antiaircraft mounts, her weapons were more a contingency than a practicality. She was a fleet oiler: bulky, wallowing, unglamorous. And absolutely essential.

She was USS Cimarron, first of eight T-3 oilers in her class. She was designed for one purpose: to transfer Bunker C-type fuel to other ships while at sea. Built for the Maritime Commission by Sun Shipbuilding in Chester, Pennsylvania, Cimarron was acquired by the Navy, designated AO-22, and commissioned at Philadelphia in March 1939, six months before the Europeans launched themselves into another Great War.

Cimarron was christened for a river that sprang from Oklahoma and drained into Kansas. Other than perhaps the Sabine, her sisters bore riverine names that most Americans had never heard, such as Salamonie (Indiana), Kaskaskia (Illinois), and Chemung (New York-Pennsylvania).

Almost three years after Cimarron’s commissioning, war had come to the other side of the planet, conferring unexpected importance upon the small family of naval oilers. Her nearest sister, Neosho (AO- 23), also with Kansas-Oklahoma roots, had survived Pearl Harbor, only to die in the Coral Sea five months later.

In March 1942, three months after the Pearl Harbor debacle, Cimarron transited the Panama Canal to join the Pacific Fleet. There she found a supporting role in the legendary operation called the First Special Aviation Project. Departing with Vice Admiral William F. Halsey’s task force, Cimarron and her sister Sabine (AO-25) pumped bunker fuel to USS Hornet (CV-8) under Captain Marc Mitscher and Halsey’s flagship Enterprise (CV-6). Aboard Cimarron, the three-hundred-man crew gawked at Hornet the first time they saw her: Sixteen Army B-25 Mitchell bombers were lashed down in place of the familiar slate-gray Navy aircraft. On April 18 Lieutenant Colonel Jimmy Doolittle’s Mitchells flew off Hornet’s rain-lashed deck six hundred miles from Japan, and Halsey’s task force hauled off. The oilers had played an obscurely vital role in America’s response to Pearl Harbor.

Less than sixty days later Cimarron refueled several ships before and after the crucial Battle of Midway. For much of 1942 into 1943 she was involved in the Guadalcanal campaign. She had even dodged enemy submarines. No other oiler had seen as much action.

By June 1944 Cimarron was an old Pacific hand. Though she remained unheralded, the headline-making Fifth Fleet would have gone nowhere without Commander A. H. Koostria’s oiler and her sisters.

That month Cimarron belonged to Unit Three of Task Group 50.17 under Captain Edward E. Paré, a Bay Stater who had graduated in the top 20 percent of the Annapolis class of 1920. With two other tankers—her old partner Sabine plus Kaskaskia—she was protected by the new Fletcher-class destroyer John D. Henley (DD-553) and two destroyer escorts, Riddle (DE-185) and Waterman (DE-740). Paré’s fueling group included six other such units plus four escort carriers, two with the standard complement of Wildcat fighters and Avenger bombers; two ferrying P-47 Thunderbolts for the Army.

Four hospital ships accompanied Task Group 50.17 to tend the inevitable casualties of an opposed landing on a hostile shore. In all, the task group boasted two dozen oilers and eighteen escorts: a sizable fleet in itself. It was an assembly worthy of an admiral, but Paré accepted the honorific of commodore: a captain in a rear admiral’s billet.

When Cimarron stood out of Majuro that Tuesday, Commander Koostria had conned her through the channel, feeling the pulsing power of 30,400 horsepower thrumming through the deck plates. Geared turbines driving twin screws could push the oiler through the water at eighteen knots, but she seldom needed to make that speed, especially with a full load. And today she rode low in the water. Her empty weight measured some 7,500 tons, but fully loaded, as now, with 146,000 barrels of fuel on board, she ran close to 25,000.

Oilers were a growth industry. Only four of Commodore Paré’s twenty-four AOs had turned a wake before Pearl Harbor; three others were less than six months in service. At war’s end the U.S. Navy owned three times as many as at the start, and that did not include gasoline tankers (AOGs). Nor did it include munitions ships or other auxiliaries necessary to sustain task forces at sea for months at a time.

Other unheralded but essential auxiliary ships belonged to Vice Admiral William L. Calhoun’s service force. His vessels included provision ships (AFs), better known as “reefers” for the dry goods they carried. The Pacific Fleet counted only nine that summer, owing to considerations on the other side of the globe. They were augmented by Merchant Marine hulls to meet the ceaseless needs of a fleet at sea as well as for corps-sized operations ashore, a thousand miles from the nearest base.

Stores munitions ships (AKSes) were called “floating general stores,” carrying everything from typing paper to steel plate. Even so, they could provide only about five thousand of the forty thousand inventory items required at a given time. Ammunition ships (AEs) provided reloads for everything from small-arms ammo to one-ton bombs and sixteen-inch main battery rounds.