and, due to limited arcs of fire from the casemate guns, four to six guns firing fore or aft. Her secondary armament consisted of two /50 caliber anti-aircraft guns in single mounts. Detroit was initially built with the capacity to carry 224 mines, but these were removed early in her career to make way for more crew accommodations. She also carried two triple and two twin, above-water, torpedo tube mounts for torpedoes. The triple mounts were fitted on either side of the upper deck, aft of the aircraft catapults, and the twin mounts were one deck lower on either side, covered by hatches in the side of the hull. The ship lacked a full-length waterline armor belt. The sides of her boiler and engine rooms and steering gear were protected by of armor. The transverse bulkheads at the end of her machinery rooms were thick forward and three inches thick aft. The deck over the machinery spaces and steering gear had a thickness of 1.5 inches. The gun turrets were not armored and only provided protection against muzzle blast and the conning tower had 1.5 inches of armor. Detroit carried two floatplanes aboard that were stored on the two catapults. Initially these were probably Vought VE-9s until the early 1930s when the ship may have operated OJ-2 until 1935 and Curtiss SOC Seagulls until 1940 when Vought OS2U Kingfishers were used on ships without hangars. Armament changes During her career Detroit went through several armament changes, some of these changes were to save weight, but others were to increase her AA armament. The lower torpedo tube mounts proved to be very wet and were removed, and the openings plated over, before the start of World War II. Another change made before the war was to increase the 3-inch guns to eight, all mounted in the ship's waist. After 1940, the lower aft 6-inch guns were removed and the casemates plated over for the same reason as the lower torpedo mounts, and in 1944, the upper fore 6-in guns were removed. The ship's anti-aircraft armament were augmented by five twin Bofors guns along with 12 Oerlikon cannons by the end of the war. Inter-war period After a shakedown cruise to the Mediterranean, Detroit joined the Scouting Fleet for exercises and maneuvers along the east coast and in the Mediterranean. From September–October 1924, she was on lifeguard station for the USAAS's round-the-world