Fast attack craft

Fast attack craft (FAC) are naval vessels that have been termed "eggshells with sledgehammers". They are not seaworthy for "blue ocean" operations, but can be a powerful part of a coastal defense force. The first versions appeared around the beginning of the twentieth century, and their "sledgehammers" were torpedoes that could cripple or sink a battleship — if the torpedo boat could survive to get into range.

The first attack craft were called "torpedo boats". To protect oceangoing battleships from coastal torpedo boats, blue-water created "torpedo boat destroyers", as vessels large enough to accompany a battle force crossing oceans, but nimble enough to fight torpedo boats.

World War II

At the beginning of the war, FAC were reasonably common in European waters, where they could operate near a coast. German Schnellboot torpedo boats were considerably larger than the vessels used in the Pacific, so they could operate in the rougher weather of the North Sea and English Channel. The British referred to the schnellboot as the "E-boat", which, depending on who was asked, referred either to an "enemy boat" or to an Eilboot (fast boat).

The Fairmile was optimized for defense against S-boots, so it did not need the speed of the oncoming attackers. It did, however, have much better radar. PT boats operated in the generally calmer waters of the Pacific so did not need to be as large for seakeeping

	German S-boot	British Fairmile D MTB	U.S. Higgins PT boat
length	35 m/115 feet	34 m/110 feet	24 m/78 feet
displacement	100 tons	106 tons	35 tons
speed	40 knots	29 knots	41 knots
armament	2 torpedo tubes, 2 20mm autocannon	4 torpedo tubes, 2 20mm, 1 6pdr gun, 2 .50 cal/12.7mm machine guns	4 torpedo tubes, 1 40mm, 2 20mm

German fast gunboats were a serious threat to transports and landing craft. By the end of the Second World War, however, surface-launched anti-ship torpedoes were obsolescent. Submarines still used torpedoes as their primary weapons, but their torpedoes were larger and more capable than those on FAC.

In the Pacific, the Japanese relied on destroyers and cruisers for torpedo attacks. The U.S. did employ "patrol torpedo" (PT) boats, usually but not always in coastal waters. When General Douglas MacArthur and his immediate entourage were evacuated from the Phillipines to Australia, they sailed in PT boats from Corregidor to Mindanao, where long-range aircraft would fly them to Australia. The journey of 560 nautical miles, taking 35 hours, was considered to be remarkable seamanship.

In a turnabout, destroyers and cruisers were the more effective anti-surface warfare torpedo launchers in WWII, especially Japanese vessels armed with the Type 93 "Long Lance" torpedo. The U.S., however, used both FAC and destroyer launched torpedoes at the Battle of Surigao Strait. The PT boat FACs were more of a nuisance to the Japanese, while the destroyers were deadly.

Early missile boats and equivalents

With the introduction of the Soviet Osa-class and Komar-class, FACs took a quantum jump in lethality, when they were equipped with anti-shipping missiles. While Egyptian Osas have been credited with the first sinking of a vessel by a ship-launched missile, the Israeli destroyer Eilat in 1967, the SS-N-2 STYX missiles may have come from Komars

Current types

Today's FAC range from light boats such as the Swedish Boghammars, armed with infantry weapons, up to heavily armed but still relatively small vessels such as the Israeli Sa'ar 5 corvettes. At the higher end of the spectrum, a ship is more a FAC due to doctrine than equipment; a Sa'ar 5 is only slightly smaller than a World War II Fletcher-class destroyer.