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Under Two Flags

Replenishment at sea during World War II was limited, for the most part, to refueling operations and whatever small amounts of cargo could be transferred by high line. The expenditure of aircraft ordnance did not become a problem until the last year of the war when air groups aboard the fast carriers began to expend more bombs than could be carried aboard ship for the sustained ground attacks now being conducted.1

The need for rearming at sea first surfaced in the closing months of 1944 as the staff of the Fifth Fleet began contemplating the invasion of Iwo Jima and Okinawa. Strategists planning this, the first assault on Japanese territory, realized that both islands were close enough to Japan to receive direct air support from the home islands. To counter this threat they directed the commander of the Fifth Fleet, Adm. Raymond Spruance, to undertake intensive air strikes against air bases in Japan proper during the assault to forestall the massive kamikaze counterattacks that were expected once the troops landed. Though Spruance planned to conduct the raids with the fast carriers of Task Force 58, he was well aware of the logistic problem involved in keeping twelve or more flattops on station almost 2,000 miles from Ulithi, the nearest advance base. The experience gained during the recently completed invasion of Leyte, had shown that carriers conducting powerful air attacks on ground targets were likely to deplete their stores of aviation ordnance after three or four days of concentrated action. Spruance understood that it would be highly advantageous to replenish the force at sea to avoid the ten- to twelve-day turnaround that would otherwise be required to steam back to Ulithi, replenish ammunition, and then return to station for further air strikes. Though refueling at sea was now a routine matter, no effort had been made to develop a means of transferring ammunition, provisions, or stores on a major scale, though the tankers had been accomplishing this feat on a limited tonnage basis for some time. A technique for transferring large amounts


of cargo at sea would allow the task force to replenish its depleted stocks of ammunition without having to return to base.

While plans for the invasion were being formulated in December 1944, Spruance directed his staff to come up with a means of replenishing a carrier's ammunition at sea so it could stay on station as long as needed.2 Within weeks, the logistic planning staff, under the direction of Capt. Burton Biggs, worked out a method of transferring cargo between AEs (cargo ships converted to carry ammunition) and the flattops under way, which made use of the standard winches, booms, and cargo nets normally carried by the AEs.

To transfer ammunition between ships using this method devised by Burton, a line from a winch on the supply ship was first led through a block on the supply ship's boom and then connected to a similar line from a winch on the carrier. Next, a hook was attached at the point where the lines were joined and fastened to a set of cargo slings attached to the load to be transferred while it was still on the supply ship's deck. The actual transfer was conducted in four steps: first, the supply ship would hoist the load above the deck; second, it would be pulled across the gap separating the ships; third, the load would be lowered to the carrier's hangar deck; and last, the empty cargo net was retrieved by the supply ship. The process was repeated as often as necessary to move the required tonnage. While this was taking place, the carrier had to hold station alongside the ammunition ship separated by about eighty feet while steaming at 8 to 10 knots. Manhandling ammunition, especially the 500- and 1,000-pound bombs, was a treacherous and somewhat dangerous activity on the decks of both ships. Bombs were simply rolled along the deck and then stopped by putting a wedge under them÷not an easy task when done on the heaving deck of a ship at sea. The system, known as the "Burton method," was first used operationally on 23 February 1945 to support the invasion of Iwo Jima. On that date the Shasta (AE-6), which had tested the procedure four days earlier with the Wrangell (AE-12), transferred ammunition to the Bennington (CV-20).3

When the Logistic Support Group (Task Group 50.8) departed Ulithi on 13 March, it was separated into four divisions, each comprised of four oilers and an ammunition ship, except for one unit of three oilers. On 16 March, the group rendezvoused with the fast carriers for the first time and spent the entire day replenishing fuel, ammunition, and stores (replacement aircraft and crews were supplied by the plane transport group). Reprovisioning was not provided until 26 March when the Mercury (AK-43) arrived from Ulithi. On that day, her first with the replenishment group, 54 tons of fresh and other provisions were transferred to Task Force 58. Though commended for her performance, the transfer of cargo was slowed because she lacked enough gear to rig more than one set of whips per side. Nevertheless, the


addition of the Mercury demonstrated that for the first time in modern naval warfare, a fleet could be completely resupplied at sea with food, fuel, ammunition, and supplies (see table 20).4

During the remaining months of the war, major elements of the Fifth Fleet were free to remain on station almost indefinitely, although individual task groups (typically three to four carriers) were rotated periodically to Ulithi, the nearest advance base, for routine upkeep and repair. The method of replenishing such a large collection of ships is so important that it bears amplification.

In the night preceding a fueling rendezvous, the group commander would determine the speed and course for safe fueling based upon a careful check of the wind, weather, sea state, and operational requirements. The speed of the oiler group was then set so that the fueling group would arrive at the rendezvous point just before dawn. The crews would rig the fueling gear ahead of time so that fueling could begin at first light. Just before daybreak, three or four oilers would form into a single line 1,500 to 2,000 yards apart steaming into the wind÷the preferred course for refueling÷at about 10 knots. A second line composed of ammunition and provision ships was formed 2,000 yards astern of the oilers. All combat ships made approaches on the issuing ships to maintain the integrity of the replenishment line. Fueling of carriers was limited to the oiler's port side since it was essential that both ships be in full view from their respective bridges (on the flattops located always on the starboard side). The same was true for replenishment from ammunition and stores ships; though it was normal to fuel a large ship and an escort at the same time, only one large ship could be rearmed at a time. While oilers and cargo ships in the replenishment line fueled, provisioned, and rearmed the fast-carrier task force, other oilers in the Logistic Support Group consolidated cargo so that those that were nearly empty could be drained allowing them to return to Ulithi where they would reload from commercial tankers sent from the United States. In addition to fuel oil

Underway Replenishment during the Invasion of Okinawa, Total Supplies Delivered

Fuel oil 10,133,000 bbls
Diesel 323,000 bbls
Avgas 25,573,000 gallons
Bombs and ammunition 16,373 tons
Replacement aircraft 998
Replacement aircrews 220
Refrigerated provisions 2,219 tons
Dry provisions 4,005 tons
Ship's stores 575 tons
Mail 15,398 bags
Passengers 1,240
Replacement personnel 1,032


and avgas, oilers dispensed drums of lube oil, belly tanks, and U.S. mail; passengers and even Japanese prisoners of war were also passed by high line.5

The system worked remarkably well. After striking at Japan for one or two days, the task force would sail all night to rendezvous with the replenishment group at first light. During some days as many as one hundred ships would be lined up along a 40-mile front as they steamed through the lines of supply ships, coming alongside oilers, breaking away, then coming alongside ammunition ships, breaking away, then coming alongside stores ships and breaking away. The task force would then spend the following night steaming to its next objective. Two days of air strikes required two nights and a day out of combat to replenish, but this was far superior to the ten or twelve days out of combat required if the task force had to return to the nearest base.

Though the effort to resupply the fleet at sea was considered a success, it was an all-day affair that could not be undertaken in the face of any serious threat of enemy action in the vicinity. Though the operation required no less than three separate maneuvers for fuel, food, and ammunition to be received, no consideration was given to improving this situation until after the war when the "lessons learned" worked their way through the naval bureaucracy. In May 1946, Fleet Admiral Nimitz, who had been appointed CNO after the war's end, began to tackle the problem by recommending construction of both a very high speed oiler and a very fast cargo ship. The former, listed as the Fast Oiler (Project 22), was intended to replenish fast task-force screens and was to be developed around the following design characteristics: sustained speed of 25 to 30 knots with full load, good subdivision with split engineering plant, strong AA battery, and capacity for 300 tons of fresh and frozen provisions and 20,000 rounds of 5-inch cargo ammunition.6

The cargo ship, identified as Project 23, would have similar characteristics, but would carry a balanced load of ammunition, stores, and provisions to replenish major combatants. Before pursuing work on either of these designs, Rear Adm. Edward L. Cockrane, chief of the Bureau of Ships, recommended that the ex-German tanker Dithmarschen (IX-301) be used "to crystallize naval opinion as to the speed and other characteristics required in future high-speed replenishment vessels for fast Task Forces."7 While neither project got off the drawing boards, Cockrane's suggestion was ultimately undertaken.

The Oiler-Supply Ship Dithmarschen

Dithmarschen, constructed at Danzig in 1938 by F. Schichau company, was built for the German navy as a specialized supply ship to support capital ships on the high seas. Although the ship looked like a typical tanker, she was the first multipurpose replenishment ship and had


Characteristics of Dithmarschen (as Built)

Length, overall 582'    
Beam 72'5"
Depth 40'5"
Draft 33'6"
Total displacement 20,850 tons
Registered tonnage 10,850 tons
Tank capacity, barrels 67,000 (42s)
Shaft horsepower, rated 22,000
Design speed 20.75 knots

SOURCE: Tanker und Versorger Der Deutschen Flotte, 1890-1980, 270.

cargo spaces for refrigerated food, dry provisions, ammunition, and general supplies in addition to 67,000 barrels of fuel oil (see table 21). The Dithmarschen was the first of five similar ships launched by Germany just prior to World War II. Though built to serve the German Navy, she carried a merchant crew and flew the German state flag rather than the Nazi naval ensign. The Dithmarschen and her sisters were the largest and fastest tankers then in service with any navy. There is no evidence that these ships were intended to provide underway replenishment, however, and all transfers of cargo and fuel were apparently done while both ships were tied up alongside.

When Germany surrendered to the Allies in May 1945, the ship was found in a small fjord in northern Norway. The Dithmarschen was ordered to Bremerhaven and turned over to British authorities. On 15 January 1946, the Inter-Allied Reparations Commission allocated Dithmarschen to the U.S. Navy as part of war reparations. Preparations were then made to bring her to Philadelphia with the crew from the Europa (AP-177), the former German liner then about to be decommissioned in Bremerhaven. U.S. naval authorities were interested in evaluating the ship's performance based on her speed, which was listed at 22 knots, and the advanced state of her engineering plant, which was rated at 1,200 pounds (psi).8 Like many other German vessels, the navy suspected her speed would be greater than that originally given out by the Kriegsmarine.9 At precisely noon on 2 May 1946, the Dithmarschen officially entered U.S. naval service bearing the designation IX-301 (IX being the prefix for unclassified vessels). The ship left Bremerhaven on 19 May, arriving at the Philadelphia Navy Yard eleven days later. The voyage was an unusual one for the crew, which had to endure a taste of old navy life when hammocks were slung from the overhead in the mess compartments to provide bunk space.10

Conversion to Replenishment Oiler

Nimitz was no stranger to the problems of replenishment at sea having participated in its development on two separate occasions. He certainly understood the importance of the one-stop replenishment concept and must have read the after action reports of Task Force 58 and


the Logistic Support Group following the operations around Okinawa. It is not surprising then, to discover that he immediately authorized the conversion of Dithmarschen for use as a prototype "oiler supply ship."11

In June, the Philadelphia yard, which was to carry out the job, issued a project order for $1 million to outfit the ship for duty with the Atlantic Fleet.12 Concern was growing within the Bureau of Ships, however, about the cost and difficulty of conversion. The absence of suitable crew space required major modifications to bring the ship's habitability up to U.S. Navy standards. The funding situation worsened when Congress cut the navy's 1947 operating budget from the $5.1 billion submitted by the secretary of the navy to $4.1 billion.13 By the end of August the project was in jeopardy of being canceled, as any funds expended on the Dithmarschen would be taken from the shrinking pool of resources needed to maintain the fleet. In an effort to save the project and save money, Rear Admiral Cockrane proposed the ship be used on an experimental basis only so the expenditure funds would be kept to a minimum.14 Word of the project's impending doom reached the ears of Capt. Edward E. Paré, who was commanding ServRon 2 in the Atlantic, the unit that the Dithmarschen would be assigned to after conversion. As mentioned in chapter 18, Captain Paré was the first officer in the U.S. Navy to command an oiling group at sea and had served as chief of staff and aide to the commander of ServRon 6 between December 1944 and January 1945÷the period when underway replenishment took off.15

Paré, who would later become an outspoken advocate of one-stop replenishment, had more than a passing interest in the Dithmarschen. In an effort to save the project, he forwarded the following comments to CNO Nimitz via his immediate superior, commander of Service Force Atlantic Fleet, and up through the chain of command via the commander of the Atlantic Fleet, Adm. Marc A. Mitscher:

It is generally agreed that the increasing range and effectiveness of aircraft will make it next to impossible to spend all day at 10-12 knots on a steady course replenishing the Fleet, while the large carriers shop around among a heterogeneous group of ships for their needs. It is vital that replenishment vessels be able to satisfy rapidly nearly all needs of combat ships at one stop. Therefore, any expenditure of funds to put such a ship in the Fleet for trial is justified.16

Admiral Mitscher, the most celebrated carrier admiral to emerge from World War II, approved Paré's statement forthwith, endorsing his conclusions that "[Dithmarschen's] temporary use on an experimental basis is considered important enough to justify the outlay of funds and manpower required."17


It looked as if the project would come to fruition on 1 October 1946 when the Dithmarschen was redesignated AO-110 and her name officially changed to the Conecuh.18 But this was not to be. Two days later Cockrane postponed the conversion indefinitely and ordered all repair work not essential to prevent serious deterioration of the effort already expended to cease, though the ship was not taken out of service until 24 October.19 The ship remained on the inactive list for the next six years, a casualty of the fearsome budget-cutting ax that struck the Navy Department in 1947.

The conversion process was not resurrected until the CNO's Conference on Mobile Logistic Support convened in April 1952. Committee No. 2, one of three set up to investigate current issues in fleet logistics, recommended that the CNO approve Conecuh's conversion to a "replenishment oiler" as previously planned, although it was clear the ship would neither "be capable of the high transfer rates desirable for underway replenishment" nor be able to carry aviation fuels.20 It took several months for this decision to work its way through the peacetime bureaucracy. Finally, on 4 September 1952, the Conecuh was redesignated AOR-110, thereby becoming the first replenishment oiler in the U.S. Navy. In addition to work remaining unfinished from the original schedule, the Philadelphia Navy Yard was directed to push to completion a number of items by 21 April, thus adding new urgency to the project that had lain dormant for so many years. These items included (1) additional berthing space for the forty-person cargo handling battalion; (2) cargo-handling gear and facilities for ammunition stowage;(3)replacement of defective insulation in seven refrigerated spaces;(4)installation of two more sound-powered telephone circuits; and(5)provision for adequate steam supply for operation of cargo pumps and cargo-handling machinery while replenishing.21

Though the yard agreed to do the work, the staff expressed anxiety over the lack of sufficient spares and the unavailability of parts for a fifteen-year-old ship built behind the Iron Curtain. Their concerns would prove to be well founded. Luckily, the man chosen to command the Conecuh, Cdr. Mason Freeman, proved to be well suited to the task.

Freeman's assignment was an unexpected opportunity that came about when he received a call from the chief of the Bureau of Personnel who told him about the navy's plans for the Dithmarschen. Although Freeman had already been detailed to a battleship as its executive officer, the chief of personnel thought that the experimental replenishment oiler would be a good command. Freeman jumped at the opportunity of commanding his own ship especially since oilers were usually assigned to captains.22


Launched as the German supply ship Dithmarschen, Conecuh (AO-110) was converted into the U.S. Navy's first replenishment oiler in 1953. The large boom facing the bow was part of two cargo-transfer stations for underway replenishment of solid cargo (U.S. Naval Institute)
Launched as the German supply ship Dithmarschen, Conecuh (AO-110) was converted into the U.S. Navy's first replenishment oiler in 1953. The large boom facing the bow was part of two cargo-transfer stations for underway replenishment of solid cargo (U.S. Naval Institute)

During the precommissioning period, Commander Freeman discussed the advisability of replacing the German-built gyro compass with a U.S. system. Although it was "one of the best in the world," there was some concern about the availability of parts for this critical apparatus since the manufacturer was now located behind the Iron Curtain. Inquiries revealed that parts were available on the world market, and it was decided to keep the original system to save money.23

Renovations took longer than expected, and the Conecuh was not commissioned until 16 February 1953. One reason for the delay was the need to modify the cargo hold to meet U.S. Navy standards for ammunition storage and handling. The only other change needed to make the ship suitable for underway replenishment was the installation of specialized rigging and the handling gear needed to transfer fuel and cargo between ships.24


Shipyard work, including three sea trials, was completed in June. The Conecuh then sailed to Norfolk for several months of refresher training in preparation for Operation Mariner scheduled for September and October.

After a shakedown cruise off the Virginia Capes, the Conecuh steamed to Geenock, Scotland, to join the Service Force of Second Fleet and participate in the Mariner exercises conducted in the North Atlantic. Despite bad weather, the ship conducted the first operation of one-stop replenishment in the U.S. Navy during this exercise. The Conecuh spent the next two months operating with a Hunter-Killer Group (HUK) in the Atlantic as the group's "sole source" of logistic support.25

After a brief stay at Norfolk, the Conecuh sailed for the Mediterranean for evaluation as a one-stop fleet supply ship with the Sixth Fleet.26 On the voyage across the Atlantic, a casualty occurred that could have prevented the ship from accomplishing her mission. As Rear Admiral Freeman explained:

I was in my bunk one evening when I noticed a breeze coming through the open port hole. I sensed something wrong and went to the bridge. I asked the helmsman, "Is anything wrong?" "No sir, we're not having any trouble following the compass," he replied. Turns out the ship was 90 degrees off course!

We let ComServLant and Buships know of our need and were advised that experts and parts would be available at Gibraltar. With that assurance I decided we could carefully disassemble the gyro and if no parts were broken could see the results of cleaning and reassembling. In twenty-four hours, the chief engineer (Ray Schneible, I hope) and I had an operating gyro system. [Freeman, who had studied German while attending the Naval Academy, read the manual while Schneible disassembled the unit.]27

The Sixth Fleet cruise provided a wealth of information on the capabilities of one-stop replenishment versus multiship replenishments. Precise records of all aspects of underway replenishment were collected throughout the evaluation period with Conecuh servicing ships of the Sixth Fleet on some eighty-seven occasions. Information was obtained for each replenishment on time needed to rig and disassemble the transfer gear; the time needed for transfer; and the amounts of fuel, stores, and ammunition delivered. Computations were then made showing the comparison with AE, AF, and AO replenishments÷ the results were all in favor of the AOR and made a convincing case for a new class of vessel based on the data obtained. Resupply was done both in port, at Naples, Italy, and at sea from ammunition ships, reefers, and oilers. While in the Mediterranean, Conecuh also participated in tests of the shuttle concept for keeping the AOR deployed in


In March 1954, Conecuh demonstrated the feasibility of providing underway replenishment while simultaneously transferring fuel via the span-wire method. Here she passes a pallet load of 5-inch ammunition. [Courtesy Rear Adm. Mason Freeman, USN (Ret.)]
In March 1954, Conecuh demonstrated the feasibility of providing underway replenishment while simultaneously transferring fuel via the span-wire method. Here she passes a pallet load of 5-inch ammunition. [Courtesy Rear Adm. Mason Freeman, USN (Ret.)]

a forward area as long as possible. Instead of returning to port for resupply, Conecuh was restocked at sea from single commodity support ships (AOs, AEs, etc.). These slower types would shuttle back and forth allowing the AOR to remain on station.28

The cruise was not without incident, however, as the ship experienced a continuous series of breakdowns exacerbated by the lack of spare parts, which had been of such concern to the shipyard. The Conecuh was kept at sea only by the efforts of her crew, which made repairs on a patchwork basis with the aid of a fleet repair ship.29 The problems included failure of gyro repeaters (replacement from behind the Iron Curtain had to be secured via diplomatic channels), continued deterioration of the original insulation installed in cold-storage spaces, ruptured boiler tubes, and loss of the ship's evaporator in midocean. Despite these shortcomings, the ship never missed a scheduled replenishment. Rear Admiral Southwick, Freeman's immediate superior, wrote: "It is actually amazing that the Conecuh (AOR-110), with her


Crewmen aboard the receiving ship had to manually stow each shell. Notice that both fuel lines are just being taken aboard. [Courtesy Rear Adm. Mason Freeman, USN (Ret.)]
Crewmen aboard the receiving ship had to manually stow each shell. Notice that both fuel lines are just being taken aboard. [Courtesy Rear Adm. Mason Freeman, USN (Ret.)]

equipment and configuration deficiencies, had been able to achieve the current (fleet) enthusiasm for the one-stop replenishment program."30 Modestly downplaying his own role, Commander Freeman (who retired with the rank of rear admiral) credits his chief engineer for keeping the ship running. According to Freeman, "He could fix anything."31 His own contributions to the success of the project did not go unnoticed, however. Writing to the chief of Naval Personnel, Rear Admiral Southwick stated: "Through his ability and determination, Commander Freeman has made and kept the ship operable in spite


Promoted during his tour of duty, Capt, (later rear admiral) Mason Freeman, commanded Conecuh during the critical period when the ship was used to evaluate the feasibility of the replenishment oiler. Though Freeman modestly credits his chief engineer for keeping the ship in service despite the numerous breakdowns experienced, it is clear that his leadership and enthusiasm contributed much to the success of this important exercise. [Courtesy Rear Adm. Mason Freeman, USN (Ret.)]
Promoted during his tour of duty, Capt, (later rear admiral) Mason Freeman, commanded Conecuh during the critical period when the ship was used to evaluate the feasibility of the replenishment oiler. Though Freeman modestly credits his chief engineer for keeping the ship in service despite the numerous breakdowns experienced, it is clear that his leadership and enthusiasm contributed much to the success of this important exercise. [Courtesy Rear Adm. Mason Freeman, USN (Ret.)]

of material difficulties of almost insurmountable nature and number."32 The leadership qualities so aptly demonstrated by Freeman while captain of the Conecuh undoubtedly contributed to his later promotion to flag rank.33

The continuing material difficulties undoubtedly contributed to the extensive overhaul that took place in the Norfolk Navy Yard from


30 June 1954 to 4 January 1955.34 Though the Conecuh rejoined the fleet after refit, she participated in only one more operation (off the Florida Keys in the late fall of 1955) before being decommissioned on 3 April 1956. In retrospect, it seems the navy wasted money on her refit, though it is likely that her importance as the only multiproduct replenishment ship in the navy enhanced her value in the eyes of the "Brass." Oilers of the new Neosho class were just entering service and the department should have realized the difficulties in trying to maintain a one-of-a-kind prewar vintage vessel of German ancestry, whose birthplace was now in Polish territory.


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Transcribed and formatted for HTML by Larry Jewell & Patrick Clancey, HyperWar Foundation