The spar torpedo was invented during the American Civil War by E. C. Singer, a private engineer who worked on secret projects for the benefit of the Confederate States of America (Singer was the nephew of Isaac Singer, inventor of the sewing machine). Singer's torpedo was detonated by means of a trigger mechanism adapted from a rifle lock.
The spring-loaded trigger was detonated by means of a long cord attached to the attacking vessel. The attacking vessel rammed its target, embedding the barbed torpedo in its hull, then backed off. When the attacker reached the limit of the trigger cord, the torpedo was detonated.
The Whitehead torpedo was the first self-propelled or "locomotive" torpedo ever developed. It was perfected in 1866 by Robert Whitehead from a design conceived by Giovanni Luppis of the Austro-Hungarian Navy.
It was driven by a three-cylinder compressed air engine invented designed and made by Peter Brotherhood. Many naval services procured the Whitehead torpedo during the 1870's. This early torpedo proved itself in combat during the Russo-Turkish War when, on January 16, 1878, the Turkish ship Intibah was sunk by Russian torpedo boats carrying Whiteheads.
The term "torpedo" comes from the Torpedo fish, which is a type of ray that delivers an electric shock to stun its prey.
Whitehead developed what he called the Minenschiff (mine ship): an 11-foot long (3.3 m), 14-inch diameter (35.5cm) torpedo propelled by compressed air and carrying an explosive warhead, with a speed of 7 knots (13km/h) and the ability to hit a target up to 700 yards (640 m) away.
In 1868, Whitehead introduced a solution to the stability problem for his torpedoin the form of a pendulum-and-hydrostat control mechanism, a self-regulating device that kept the torpedo at a constant preset depth. Still, there remained the problem of course correction: how to return the torpedo to its correct course after it had deviated due to wind or wave action. The solution was in the form of the gyroscope gear, which had been recently invented by Ludwig Obry, who was also a naval officer.
The Austrian Navy bought the manufacturing rights to the Whitehead torpedo in 1869, and by 1870 Whitehead's torpedoes were running at 17 knots (31.5km/h).
The United States Navy started using the Whitehead torpedo in 1892 after an American company, E. W. Bliss, secured manufacturing rights. As manufactured for the US Navy, the Whitehead torpedo was divided into four sections: the head, the air flask, the after-body and the tail. The head contained the explosive charge of guncotton; the air flask contained compressed air at 1,350 pounds per square inch, or 90 atmospheres; the after-body contained the engine and the controlling mechanism, and the propellers and rudder were in the tail. The air flask was constructed from heavy forged steel. The other parts of the shell were made of thin sheet steel. The interior parts were generally constructed out of bronze. The torpedo could be launched from above or below the waterline, using air pressure or a gunpowder discharge.
In 1871, the Royal Navy bought manufacturing rights, and started producing the torpedo at the Royal Laboratories at Woolwich, England. The Royal Navy fitted the Whitehead torpedo on its earliest submarines, from the HMS Holland 1 onwards. In 1904, British Admiral Henry John May commented, "but for Whitehead, the submarine would remain an interesting toy and little more".
By 1877, the Whitehead torpedo was attaining speeds of 18mph for ranges of 830 yards.
By the 1880's, the French, German, Italian, Russian navies followed suit and began acquiring the Whitehead torpedo and deploying torpedo boats to carry them into battle.
The last known operational use of a Whitehead torpedo was during the Battle of DrÝbak Sound in the early stages of World War II.