USS Aramis (SP-418/PY-7) was a yacht acquired by the United States Navy during World War I which served as a patrol boat off New York City, was then fitted with an experimental "underwater detection system" and depth charges as an anti-submarine vessel, and was briefly the flagship of a battleship squadron.

Underway from the ordnance pier at Sandy Hook at 11:50 on 20 November, bound for the Scotland and Ambrose Lightships, Aramis received orders by semaphore from the tug Cayuga to report forthwith to the New York Navy Yard.

Arriving at 17:15 for further orders, Aramis shifted to the Jersey Central Railroad Pier the next morning where she was briefly visited by Secretary of War Newton D. Baker.

There, off Fort Trumbull, a launch from the cruiser Chicago, the flagship for the Submarine Force, Atlantic Fleet, came alongside on the morning of 18 January bearing Lt. Comdr.

As she continued onward she passed through "considerable wreckage" on the "steamer track" 10 miles east of Middle Ground Light, flotsam that included hatches and parts of heavy decking.

On the 28th, she shifted to the Ammunition Depot at Fort Lafayette, and there took on board four Mark I depth charges, the most primitive type, which required no fixed launcher — only a strong sailor to heave it over the side.

Now equipped with listening gear and an anti-submarine warfare (ASW) capability, albeit primitive, Aramis returned to the business of patrolling the waters of the 3rd Naval District assigned her.

Her regimen remained the same into August, and she spent the first few days of that month engaged in "listening" on station near Ambrose Lightship, alternating with Tarantula (SP-124) and Sabalo (SP-225), and the submarine chasers SC-52, SC-53, and SC-56.

At 18:45, Aramis came upon the captain and crew (30 men in all) of the Norwegian steamer Sommerstad, three days out of Halifax, Nova Scotia, which had been torpedoed and sunk by the German submarine U-117 that morning.

After casting Somerstad's motor sailer—in a leaky condition—adrift, Aramis reached the Barge Office at the Battery, New York City, at 11:05 on the 13th, where the Norwegians were sent ashore to be aided by their consul.

While returning to her section base at 15:55 the next day, Aramis' forward lookout spotted what looked like a floating spar about 300 yards off the starboard bow.

After her attempts to reach that vessel by radio failed, Aramis fired a blank charge to attract Hauoli's attention, and the patrol boat came alongside at 18:00.

No logs exist for Aramis' activities over the next four months, but extant message traffic reveals that she was detached from the 3rd Naval District on 18 September for use as a division commander's flagship and was directed to proceed to Base Two (Yorktown, Virginia) and report to the Commander-in-Chief, Atlantic Fleet.

The message traffic indicates that she proved to be unsuitable for her new task; and, on 3 December, Owera was ordered to proceed to relieve Aramis as flagship for the Commander of Battleship Division 3.

Limping into Lewes, Delaware, on the afternoon of 20 December, Aramis finally reached New London by the end of the year, since when her log resumed on 1 January 1919, she was at that port, moored at Dock "D", Submarine Base.

At 11:00, Aramis sighted a British freighter on a converging course and swung to the right side of the shipping channel in order to give the merchantman the advantage of deeper water.

Tilt, in making his protest over the handling of the British merchantman, reported what followed: "The steamer ... in going under our stern came so close that had the Aramis not thrown the wheel hard over left a collision would have occurred."

She cruised to New London and back in late July before receiving orders, dated 9 August 1919, sending her to the Potomac River as the prospective relief for Sylph.

Early the following year, it had been thought that Aramis would ultimately relieve Sylph, but the cost of necessary work to the former apparently caused a rethinking of the idea, and it was accordingly dropped between March and June, 1921.

Towed by the fleet tug Iuka, Aramis reached the reserve basin at the Philadelphia Navy Yard on 9 October 1923 and remained inactive until redesignated as a "District Craft, Unclassified," in late 1924.

For the next nine years, the yacht remained in operation, kept in repair by the crew of Nokomis as that ship conducted important surveys based at Cárdenas on the northeastern coast of Cuba.