At the time of his graduation from the Naval Academy, midshipmen had to serve two years service at sea before being commissioned, so he reported for duty with the crew of the new
battleship . This was one of the battleships of the
Great White Fleet sent by
President Theodore Roosevelt on an epic voyage around the world in 1907. In 1909, Carpender was transferred to the . He was commissioned as an
ensign in the
United States Navy on 6 June 1910. Leaving the
Marietta in March 1911, Carpender was involved with the fitting out of the new battleship . Landing mid-morning on 21 April, the sailors remained under fire on the beachhead until early the next morning when they began their advance through Veracruz. After a series of street fights, they captured the town shortly before noon on 22 April. For his part in the engagement, Carpender was awarded the
Navy Distinguished Service Medal.
Between the wars Carpender returned to the United States in April 1919, and became a Member of the Naval Examining Board, and Judge Advocate General of the General Court Martial at the
Naval Training Station Great Lakes. In August 1921 he assumed command of the . He reported to the
Naval Submarine Base New London for training in June 1922, after which he was posted to the
United States Asiatic Fleet as commander of Submarine Division 14. In August 1923 Carpender returned to Washington, D.C., where he served ashore for the next two years in the
Bureau of Navigation, before becoming executive officer of the in December 1925. He was assigned to the Receiving Ship, New York, from October 1926 until March 1927, when he assumed command of the destroyer . On 11 September 1942, Carpender succeeded Leary as commander of both the Southwest Pacific Force and the Allied Naval Forces, Southwest Pacific Area. In the former role, he reported to the Commander in Chief,
United States Fleet,
Admiral Ernest J. King; in the latter he was answerable directly to the Commander in Chief, Southwest Pacific Area,
General Douglas MacArthur. The new post came with a promotion to the rank of vice admiral, but Carpender was not the most senior naval officer in the theater, as the
Royal Australian Navy′s
Admiral Sir
Guy Royle and the
Royal Netherlands Navy′s Vice Admiral
Conrad Helfrich were both senior to him. The Southwest Pacific Force was small; when Carpender assumed command, it consisted of just five cruisers, eight destroyers and 20 submarines. In October, Carpender rebuffed a request for the Allied Naval Forces to transport troops to
Cape Nelson. Carpender refused as there was no adequate
hydrographic survey of that part of the Papuan coast, making it dangerous to sail at night, and movements in the area by day were subject to attack from Japanese aircraft. A survey was conducted in October and
lighters and
luggers began making their way up the coast to Cape Nelson, escorted on occasion by Royal Australian Navy
corvettes. In November 1942, Carpender turned down a similar request from the Commander of Allied Land Forces,
General Sir
Thomas Blamey, for the Allied Naval Forces to escort some small transports to
Oro Bay, as the
Imperial Japanese Navy was doing during the
Battle of Buna–Gona. However, Carpender subsequently relented somewhat and, starting in December, small ships escorted by corvettes carried out
Operation Lilliput to deliver vital supplies to Oro Bay. During the
Pacific Military Conference in March 1943, MacArthur's chief of staff,
Major General Richard K. Sutherland, spoke to Admiral King and expressed his dissatisfaction with Carpender. On 15 March 1943, the Southwest Pacific Force, known colloquially as "MacArthur’s Navy", became the
Seventh Fleet. It remained very small. The Seventh Fleet acquired an amphibious force under the command of Rear Admiral
Daniel E. Barbey. This eventually became the
VII Amphibious Force, but for some time most of its strength was only on paper, or
en route to Australia from the United States. Observing the capabilities of
PT boats during his evacuation from the Philippines, MacArthur encouraged their use, although initial results were disappointing. Carpender made effective use of them during the
Battle of the Bismarck Sea on 25 March 1943. Carpender oversaw the Seventh Fleet's operations during the early stages of
Operation Cartwheel, MacArthur's advance towards the main Japanese base at
Rabaul. A crisis arose during the
Battle of Finschhafen, when Carpender became reluctant to reinforce the Australian position. As the situation at Finschhafen became increasingly precarious,
Lieutenant General Sir
Edmund Herring grew frustrated with Carpender's attitude, and appealed to Blamey, who in turn took up the matter with MacArthur. On 29 September 1943, Carpender agreed to use
high-speed transports to send an additional battalion to Finschhafen, and the crisis passed. Carpender told Lieutenant General
Frank Berryman that he "resented the implication that
Uncle Sam's Navy was letting [the Australians] down at Finschhafen." Carpender was replaced by Admiral
Thomas C. Kinkaid on 26 November 1943. For his services in the Southwest Pacific, he was awarded the
Army Distinguished Service Medal by MacArthur, and the
Legion of Merit by the Navy. He was also appointed an honorary
Commander of the Order of the British Empire on the recommendation of the Australian government, and a Grand Officer of the
Order of Orange-Nassau by the Netherlands. He returned to the United States, where he commanded the
Ninth Naval District from 3 January 1944 until 31 August 1945, for which he was awarded a second Legion of Merit. He retired from the Navy on 1 November 1946, In 1948, he was elected Superintendent of the private,
college-prep school
Admiral Farragut Academy in
Pine Beach, New Jersey (today located in
St. Petersburg, Florida), succeeding Brig. Gen. C. S. Bradford. ==Personal life==