The first USA torpedo, it was smaller and cheaper than the British Whitehead and required no air flask, a difficult thing for the USA to manufacture at the time. As it was flywheel powered, this torpedo did not leave a wake and could steer a straighter course than the Whitehead as its flywheel acted as a gyroscope. The flywheel was spun up by a small steam turbine mounted on the torpedo tube and drove two shafted propellers. The propellars were variable pitch and were designed to maintain a constant forward speed as the flywheel slowed. Thirty torpedoes were ordered in 1889 with twenty more being ordered in 1894. Placed in service in 1895 and removed in 1903. Difficulties and delays in production led the Navy to investigate the Whitehead torpedoes.

The US Navy negotiated for the Whitehead torpedo patent rights with a license to build torpedoes in the USA being granted in 1891. The Navy awarded a contract to the E.W. Bliss company on 19 May 1891 for 100 torpedoes to an improved Whitehead design. Compared to the Howell, they were much better depth-keepers but less accurate.

Somewhat confusingly, the Whitehead Mark 1 and Mark 2 torpedoes were built both in a 3.55 m (140 inch) version and in a 5.0 m (197 inch) version. The shorter ones were known as the "3.55 m x 45 cm Whitehead" torpedoes while the longer ones were known as the "5.0 m x 45 cm Whitehead" torpedoes. The Whitehead Mark 3 was built only in a 3.55 m (140 inch) version. The longer torpedoes and the Mark 3 were redesigned with letter codes in 1913, as described below.

Manufactured by Bliss, these were a longer version of the basic design. Also known as the "5.0 m x 45 cm Whitehead" when first manufactured, it was designated as the "Type B" in 1913. After tests with the Whitehead Mark 3 torpedo (described below), the last forty of these "Long" Mark 1 torpedoes were given a gyro which had been patented by Ludwig Obry in 1896. This improved the horizontal deviation by 300 percent compared to the earlier Mark 1 torpedoes to +/- 8 yards (7 m) at 800 yards (730 m). However, this gyro proved very hard to maintain.

Minor improvement of the Whitehead Mark 1.

Developed from the 197 inch (5 m) Whitehead Mark 1, but used 20 percent more air pressure to obtain a significantly greater range. Designated Type C in 1913.

This was the first US torpedo to be equipped with a gyro which greatly improved accuracy, otherwise it was a minor improvement of the Whitehead Mark 2.

The A through D class submarines originally fired this torpedo, but the C and D classes were modified around 1912 to use any of the longer, more powerful 204 inch (5.2 m) torpedoes.

F.M. Leavitt was a Bliss engineer. This design was a substantially improved torpedo, the first to use air heating which gave it much greater range than the compressed cold-air powered Whitehead. This new torpedo had a two stage, single wheel turbine set perpendicular to the propeller shaft to in an attempt to avoid torque problems, but the design still produced an unbalanced torque and unwanted gyroscopic effects. These tended to make the torpedo roll. Used a single 4-blade propeller.

The original Bliss-Leavitt Mark 1 was an experimental torpedo with two built in 1903 but not issued to the fleet. 200 more were ordered on 4 November 1905. Fifty additional torpedoes of the Mod 1 improved design were ordered on the same date. By 1912 all Mark 1 and Mark 1 Mod 1 torpedoes had been converted to the Bliss-Leavitt Mark 1 Mod 2 standard (no details available) and then redesignated as Torpedo Mark 1 in 1913.

Introduced two countra-rotating turbine wheels which drove contra-rotating propellers to overcome the unbalanced torque of the Mark 1. This propulsion system eliminated the rolling problem at a slight cost in range and speed. This propulsion arrangement was used on all subsequent USA torpedoes until after World War II. Designated as Torpedo Mark 2 in 1913.

Basically a Bliss-Leavitt Mark 2 with increased range. 208 ordered in 1909 and 1910. Designated as Torpedo Mark 3 in 1913.

First USA torpedo designed specifically for submarines. Twenty-one inch (53.3 cm) torpedoes were too heavy and too bulky for the submarines of the time. For that reason, this torpedo was designed as a scaled down version of the Bliss-Leavitt Mark 3. Designated as Torpedo Mark 4 in 1913. Used by C and D class submarines.

First torpedo in US service that was built by a foreign company. Manufactured by the Whitehead facility in Weymouth, UK. Later, this design was manufactured under license by the US and became the first torpedo built at the Newport Facility. First major improvement to the original Whitehead engine in that a heater was used for the air feed, which increased the range by a factor of five.

This was the first US torpedo that could be set for any one of three speeds. However, the speed had to be set before the torpedo was loaded into the tube, which limited its tactical flexibility.

This was the last piston engine used in USN torpedoes until the Mark 46. Replaced by the Bliss-Leavitt Mark 7.

The Bliss-Leavitt Mark 6 introduced a new turbine configuration in which the wheels were horizontal. This configuration has been the most common choice for USN torpedo turbine systems ever since. 100 were ordered in 1909.

First wet-heater (water spray into combustion chamber) torpedo in the US Navy. 240 ordered in 1912. Still being used by old submarines during World War II. Some Mark 7 torpedoes were modified for use by aircraft (see below).

Smaller version of the Mark 7 developed to fit the shorter torpedo tubes on old submarines. Never deployed for that purpose, but used during early aircraft tests. After a series of drops with dummy torpedoes, a live Type D was successfully launched from an R-6L Navy floatplane on 14 July 1919. 43 more Type D torpedoes were launched from planes during the next 12 months.

The first experimental USN aircraft drops with Mark 7 torpedoes were made in May 1920 at the Naval Air Station, Anacostia, Maryland, using two Mark 7 Mod 5 torpedoes. Air speed for these drops is believed to have been 50 to 55 knots at altitudes of 18 and 30 feet (5 and 9 m). It was found that the torpedo dropped from 30 feet (9 m) was badly damaged while the one dropped from 18 feet (5 m) was not. Torpedoes were then modified by strengthening them for shock, installation of exploder safety pin and attachment of a nose drogue.

The first mass torpedo practice against a live target was conducted off the Virginia capes on 22 September 1922 by 18 PT aircraft of Torpedo and Bombing Plane Squadron One. The squadron attacked the designated target, Arkansas (BB-33), which was one of a formation of three battleships which were maneuvering while running at full speed. The attack lasted over a 25 minute period during which time the aircraft approached the ships from both sides and released 17 Mark 7 Mod 1 "A" torpedoes at distances of 500 to 1,000 yards (450 to 900 m). Eight hits were made on the designated target. Subsequent analysis emphasized the artificialities which prevented the practice from demonstrating combat capability of either the surface or air units, but the outstanding fact demonstrated was that torpedoes could be successfully launched from aircraft and be made to run straight.

During trials in 1924, Mark 7 torpedoes were successfully launched from DT-2 torpedo planes at an air speed of 95 knots and from an altitude of 32 feet (10 m).

Aircraft torpedoes of this type were eventually replaced by the Mark 13.

First 21" x 21' (53.3 cm x 6.5 m) USN torpedo. Later versions starting in 1923 - Mod 5, 6 and 8 - had much larger warheads. These torpedoes were still being used on older destroyers and PT boats during World War II. It is possible that a higher speed setting was available for the torpedoes issued to PT boats.

This torpedo was supplied to Britain for use on Lend-Lease Destroyers in 1940. Torpedoes issued to Britain are listed as having a warhead of 380 lbs. (172 kg) TNT and a range of 14,000 yards (12,800 m) at 27 knots.

The Mark 8 Mod 3C differed from Mod 3A and 3B by having air-sustained gyros and a different igniter.

The Mark 8 Mod 3E was an export torpedo supplied at least to Brazil after 1936. It was nearly identical to the Mark 8 Mod 3A.