A motorboat, speedboat or powerboat is a boat that is exclusively powered by an engine.
Some motorboats are fitted with inboard engines, others have an outboard motor installed on the rear, containing the internal combustion engine, the gearbox and the propeller in one portable unit. An inboard-outboard contains a hybrid of an inboard and an outboard, where the internal combustion engine is installed inside the boat, and the gearbox and propeller are outside.
There are two configurations of an inboard, V-drive and direct drive. A direct drive has the powerplant mounted near the middle of the boat with the propeller shaft straight out the back, where a V-drive has the powerplant mounted in the back of the boat facing backwards having the shaft go towards the front of the boat then making a V towards the rear.
Overview
A motorboat has one or more engines that propel the vessel over the top of the water. Boat engines vary in shape, size, and type. Engines are installed either inboard or outboard. Inboard engines are part of the boat construction, while outboard engines are secured to the transom and hang off the back of the boat. Motorboat engines run on gasoline or diesel fuel. Engines come in various types. Engines vary in fuel types such as gasoline, diesel, gas turbine, rotary combustion or steam. Motorboats are commonly used for recreation, sport, or racing. Boat racing is a sport where drivers and engineers compete for fastest boat. The American Powerboat Association (APBA) splits the sport into categories. The categories include inboard, inboard endurance, professional outboard, stock outboard, unlimited outboard performance craft, drag, modified outboard, and offshore. Engines and hulls categorize racing. The two types of hull shape are runabout and hydroplane. Runabout is a v-shape and hydroplane is flat and stepped. The type of hull used depends on the type of water the boat is in and how the boat is being used. Hulls can be made of wood, fiberglass or metal but most hulls today are fiberglass.
High performance speedboats can reach speeds of over 50 knots. Their high speed and performance can be attributed to their hull technology and powerful engine. With a more powerful and heavier engine, an appropriate hull shape is needed. High performance boats include yachts, HSIC (high speed interceptor craft) and racing powerboats.
A V-type hull helps a boat cut through the water. A deep V-hull helps keep the boat's bow down at low speeds, improving visibility. V-hulls also improve a boat's speed and maneuvering capabilities. They stabilize a boat in rough conditions.
History
Invention
Although the screw propeller had been added to an engine (steam engine) as early as the 18th century in Birmingham, England, by James Watt, boats powered by a petrol engine only came about in the later part of the 19th century with the invention of the internal combustion engine.
The earliest boat to be powered by a petrol engine was tested on the Neckar River by Gottlieb Daimler and Wilhelm Maybach in 1886, when they tested their new "longcase clock" engine. It had been constructed in the former greenhouse (converted into a workshop) in Daimler's back yard. The first public display took place on the Waldsee in Cannstatt, today a suburb of Stuttgart, at the end of that year. The engine of this boat had a single cylinder of 1 horse power. Daimler's second launch in 1887 had a second cylinder positioned at an angle of 15 degrees to the first one, and was known as the "V-type".
The first successful motor boat was designed by the Priestman Brothers in Hull, England, under the direction of William Dent Priestman. The company began trials of their first motorboat in 1888. The engine was powered with kerosene and used an innovative high-tension (high voltage) ignition system. The company was the first to begin large scale production of the motor boat, and by 1890, Priestman's boats were successfully being used for towing goods along canals.
Another early pioneer was Mr. J. D. Roots, who in 1891 fitted a launch with an internal combustion engine and operated a ferry service between Richmond and Wandsworth along the River Thames during the seasons of 1891 and 1892.