Appointed from Georgia, he was admitted to the United States Naval Academy in Annapolis, Maryland, on 21 May 1901,[1] and began his schooling there on 21 June 1901.

[2] The 1905 edition of the school yearbook, the Lucky Bag, described him as cheerful and polite, successful in all his endeavors except the academic study of mathematics, and an expert ice skater, and it listed his activities as including baseball, American football, gymnastics, riflery[3] — he was a skilled rifle marksman[4] — and various social positions.

[3] Among his classmates were several future World War II admirals including: Harold G. Bowen Sr., Arthur B. Cook, Wilhelm L. Friedell, William R. Furlong, Stanford C. Hooper, Royal E. Ingersoll, Byron McCandless, Herbert F. Leary, John H. Newton, Chester W. Nimitz, Harry E. Shoemaker, John M. Smeallie, and Walter B.

He was promoted to lieutenant (junior grade) on 31 January 1910[7] and by the beginning of 1911 was serving aboard the battleship USS Georgia,[7] which conducted peacetime training during his tour.

In 1915, he transferred to the battleship USS Virginia,[11] which operated along the East Coast of the United States until going into reserve for an overhaul early in 1916.

[13] Late in 1917, he left the navy yard to become the first commanding officer of the armed yacht USS Yacona (SP-617) when she was commissioned on 10 December 1917 for World War I convoy escort and antisubmarine duty in the Atlantic Ocean.

[14][15] By March 1918, Wilcox was flag secretary on the staff of commander, Battleship Force 2, United States Atlantic Fleet, and he received the Navy Cross for distinguished service during that duty.

[32] On 23 August 1938, Wilcox took command of the Special Service Squadron in the Panama Canal Zone[33] — flying his flag first aboard the gunboat USS Erie (PG-50) and from 14 January 1939 aboard the gunboat USS Charleston (PG-51)[34] — until relieved by Rear Admiral H. Kent Hewitt on 3 August 1940.

With Wilcox aboard Washington, the task force departed Casco Bay, Maine, on 26 March 1942, bound for Scapa Flow.

[42] On the morning of 27 March 1942, the second day of the voyage, Wilcox appeared unaccompanied and without a coat on Washington's deck while Task Force 39 was pushing through heavy seas off Sable Island in stormy North Atlantic winter weather.

About 80 minutes after Wilcox went overboard, the destroyer USS Livermore (DD-429) sighted his body floating face down in the rough seas, but the bad weather prevented its recovery, and it was never seen again.

[45][46] Immediately after Wilcox's death, Rear Admiral Robert C. Giffen aboard Wichita took command of Task Force 39.

Witnesses disagreed on Wilcox's mental state; there were claims that he seemed sad or nervous on the morning of 27 March and that he had exhibited unstable behavior in recent days, but these were balanced by other witnesses who said he seemed of sound mind and that, although he was known to exhibit eccentricities not common among officers of his grade, his behavior otherwise was not unusual on the morning of his death.

[45][47][4] Decades later, a new hypothesis surfaced based on the reports of Wilcox seeming pale and white while on deck on the morning of 27 March, speculating that he may have been seasick and had rushed to the ship's side to vomit, but had mistakenly selected an area where lifelines were not rigged, falling overboard as a result.