A straight-14 engine or inline-14 engine is a fourteen-cylinder internal combustion engine

Internal combustion engine

The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

 with all fourteen cylinders

Cylinder (engine)

A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...

 mounted in a straight line along the crankcase

Crankcase

In an internal combustion engine of the reciprocating type, the crankcase is the housing for the crankshaft. The enclosure forms the largest cavity in the engine and is located below the cylinder, which in a multicylinder engine are usually integrated into one or several cylinder blocks...

. A straight-14 is a very long engine, and therefore only suitable for marine engineering

Marine propulsion

Marine propulsion is the mechanism or system used to generate thrust to move a ship or boat across water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting a motor or engine turning a propeller, or less frequently, in jet...

 installations in large ship

Ship

Since the end of the age of sail a ship has been any large buoyant marine vessel. Ships are generally distinguished from boats based on size and cargo or passenger capacity. Ships are used on lakes, seas, and rivers for a variety of activities, such as the transport of people or goods, fishing,...

s.

The only engine of this type known to have been built is a member of the Wärtsilä-Sulzer RTA96-C

Wärtsilä-Sulzer RTA96-C

The Wärtsilä RT-flex96C is a two-stroke turbocharged low-speed diesel engine designed by the Finnish manufacturer Wärtsilä. It is currently considered the largest reciprocating engine in the world, designed for large container ships, running on heavy fuel oil...

 family. It is a huge two-stroke diesel engine

Diesel engine

A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

 for use in container ship

Container ship

Container ships are cargo ships that carry all of their load in truck-size intermodal containers, in a technique called containerization. They form a common means of commercial intermodal freight transport.-History:...

s. The engine became well-known due to photos taken at the Aioi Works in Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

, which subsequently spread through blog

Blog

A blog is a type of website or part of a website supposed to be updated with new content from time to time. Blogs are usually maintained by an individual with regular entries of commentary, descriptions of events, or other material such as graphics or video. Entries are commonly displayed in...

s.

The 14-cylinder version of this modular engine displaces 1556000 cubic inches (25,518.4 l), with a 38 inches (97 cm) cylinder bore and 98 in (249 cm) piston stroke. The engine is 89 feet (27.1 m) long, 44 ft (13.4 m) high, and weighs 2300 tonnes (2,264 LT).

If built, the 14-cylinder variant of the MAN B&W K108ME-C

MAN B&W K108ME-C

The MAN B&W K108ME-C is a low speed two-stroke turbocharged diesel engine for marine engineering applications. It is designed by the Danish department of the German diesel engine supplier: MAN Diesel SE, the former MAN B&W Diesel group, and part of the larger MAN SE.If the largest version is ever...

would be even larger at nearly 33 metres (108 ft) long, and over 2800 tonnes (2,755.8 LT), and more powerful at 97300 kW.