Bomber destroyer

File:Lockheed P-38J Lightning - 1.jpg

Lockheed P-38 Lightning, a bomber destroyer.

A bomber destroyer is a former type of fighter aircraft dedicated to destroying enemy bomber aircraft. It is similar in purpose to the interceptor, but differs in its place in the anti-aircraft command structure, which is the source of the design differences. An interceptor is intended to respond instantly to a specific sudden threat at the limit of detectability and destroy it as quickly as possible, so it must be a fast-climbing plane (and therefore small, meaning lightweight) and need not patrol at altitude for a later target. A bomber destroyer could be slow-climbing, because the threat was habitual, or with an uncertain target, or so large as to make for a long air battle, or detected at a longer range, with plenty of time to reach bomber altitude. They could therefore be heavier, and the weight was taken up by extra fuel (which would enable longer time aloft) and heavier armament, which would necessitate twin engines. They also differ from night fighters, although often based on the same airframe, as they lack radar and are intended only for day use.

A number of nations developed such aircraft prior to World War II, all in order to provide an aircraft with enough weapon load, given the limited engine power of the era, to quickly destroy a bomber. Primary among these pre-war designs were several French and German multi-role aircraft. The United States created designs like the Bell FM-1 Airacuda and the fast-climbing Lockheed P-38 Lightning, both of which were designed explicitly to mount 37 mm cannon armament for this mission.

Developments in armament, notably the introduction of the 20 mm cannon, generally led to the disappearance of the bomber destroyer from most air forces. Even small fighters, like the Supermarine Spitfire, were able to carry enough firepower to effectively deal with German and Japanese bombers, generally two-engine planes.

The same was not true for the Luftwaffe, who were facing larger, four-engined long-range bombers that proved to be extremely difficult to shoot down. Starting in about 1943 the Luftwaffe started fielding an increasing number of bomber destroyers, mostly based on the Messerschmitt Bf 110 and Junkers Ju 88. While the German Zerstörer (destroyers) had been conceived as multi-role aircraft, the bomber destroyer role was given priority later and these planes proved to be very effective against US bomber raids in 1943 as they could employ heavy-calibre Bordkanone series cannon armament, such as the BK 5 gun, as well as rockets fired from long range. However, while they were effective weapons platforms against bombers, they lacked the performance to deal with single-engined fighters. When the P-51 Mustang began to escort the USAAF bomber raids in early 1944, the Bf 110 and other destroyers suffered heavy losses and soon had to be withdrawn from daylight combat.

Determined to stop the allied air offensive, German aircraft designers came up with various radical proposals for improved bomber destroyers, some of which involved converting bombers into flying anti-aircraft platforms.

Later German designs concentrated on dedicated high-speed fighter planes for this role, notably the Dornier Do 335 Pfeil. Its speed would allow it to remain out of danger from the Mustangs, while still carrying a massive gunload. The Messerschmitt Me 262 also saw widespread use in the destroyer role, where its huge load of four 30 mm cannons and the first truly effective air-to-air rockets proved to be highly capable. In the last months of the war many manufacturers proposed and experimented with a range of extraordinary small aircraft, propelled often by rockets and rudimentary jet engines in a desperate effort to knock more Allied bombers out of the sky. But in general, few new designs of any sort saw action due to the rapidly deteriorating war conditions.

The airborne adaptation of the Germans' Nebelwerfer ground barrage rocket, the Werfer-Granate 21, were used on some destroyer designs, and many fighters could mount the late-war R4M rocket, which proved highly effective against bombers.

After the war, fighter firepower increased steeply:

• Due to the introduction of improved high-speed revolver cannons, notably the British ADEN, French DEFA and American M39 - all of which were based on the German Mauser MG 213 developed at the end of World War II. These guns could fire 30 mm rounds at rates similar to two 20 mm cannons of the typical World War II aircraft, the larger rounds giving them considerably more explosive power. A single one of these cannon provided any aircraft with enough firepower to be a reasonable destroyer, even light interceptors.
• The resurrection of the American-invented gatling gun after World War II for aircraft armament by the US military, but driven with an electric motor instead of the hand-cranked original version of nearly a century earlier, as the M61 Vulcan 20mm cannon, for an even-faster rate of fire than any revolver cannon could hope to achieve.
• Unguided air-to-air missiles, pioneered by the Luftwaffe in World War II, were developed into highly effective weapons systems, often incorporating a radar and a targeting computer for maximum effectiveness. Canadian designs moved to all-rocket armament by the early 1950s, followed closely by US designs such as the F-89 Scorpion.

Though the threat of nuclear bombs carried by long-range bombers was met by fighter aircraft purpose-built for the destruction of these bombers, the destroyer classification disappeared almost instantly after World War II to be replaced by the interceptor classification.

When radar and night-fighting capabilities becoming standard for fighter designs and the guided missile was introduced, the distinction between the different fighter classifications gradually vanished. The intercontinental ballistic missile finally reduced the nuclear bomb-armed long-range bomber to a secondary role, and the interceptor classification dropped into insignificance as a result.

See also

• interceptor aircraft
• night fighter

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Bomber destroyer".