A fighter-bomber is a fighter aircraft that has been modified, or used primarily, as a light bomber or attack aircraft. It differs from bomber and attack aircraft primarily in its origins, as a fighter that has been adapted into other roles, whereas bombers and attack aircraft are developed specifically for bombing and attack roles.
Although still used, the term fighter-bomber has less significance since the introduction of rockets and guided missiles into aerial warfare. Modern aircraft with similar duties are now typically called strike fighters.
Development Prior to World War II, general limitations in available engine and aeronautical technology required that each proposed military aircraft have its design tailored to a specific prescribed role. Engine power grew dramatically during the early period of the war, roughly doubling between 1939 and 1943. The Bristol Blenheim, a typical light bomber of the opening stages of the war, was originally designed in 1934 as a fast civil transport to meet a challenge by Lord Rothermere, owner of the Daily Mail. It had two Bristol Mercury XV radial engines of each, a crew of three, and its payload was just of bombs.Warner, G. The Bristol Blenheim: A Complete History. London: Crécy Publishing, 2nd edition 2005. The Blenheim suffered disastrous losses over France in 1939 when it encountered Messerschmitt Bf 109s, and light bombers were quickly withdrawn.Warner, G. The Bristol Blenheim: A Complete History. London: Crécy Publishing, 2nd edition 2005. .
In contrast, the Vought F4U Corsair fighter—which entered service in December 1942—had in common with its eventual U.S. Navy stablemate, the Grumman F6F Hellcat and the massive, seven-ton USAAF Republic P-47 Thunderbolt—a single Pratt & Whitney R-2800 Double Wasp radial engine of in a much smaller, simpler and less expensive single-seat aircraft, and was the first aircraft design to ever fly with the Double Wasp engine in May 1940. With less airframe and crew to lift, the Corsair's ordnance load was either four High Velocity Aircraft Rockets or of bombs; a later version could carry eight rockets or of bombs. The massive, powerful 18-cylinder Double Wasp engine weighed almost a ton—half as much again as the V12 Rolls-Royce Merlin and twice as much as the 9-cylinder Bristol Mercury that powered some heavy fighters.
Increased engine power meant that many existing fighter designs could carry useful bomb loads, and adapt to the fighter-bomber role. Notable examples include the Focke-Wulf Fw 190, Hawker Typhoon and Republic P-47 Thunderbolt. Various bombing tactics and techniques could also be used: some designs were intended for high-level bombing, others for the low-level semi-horizontal bombing, or even for low-level steep dive bombing as exemplified by the Blackburn Skua and North American A-36 Apache.David, Donald ed, The complete encyclopaedia of world aircraft. Noble and Barnes, New York 1977 .
Larger twin-engined aircraft were also used in the fighter-bomber role, especially where longer ranges were needed for naval strikes. Examples include the Lockheed P-38 Lightning, the Bristol Beaufighter (developed from a torpedo bomber), and de Havilland Mosquito (developed from an unarmed fast bomber). The Beaufighter MkV had a Boulton-Paul turret with four 0.303 in (7.7 mm) machine guns mounted aft of the cockpit but only two were built.Buttler, Tony. British Secret Projects - Fighters and Bombers 1935-1950. Hinckley, UK: Midland Publishing, 2004. . Bristol's Blenheim was even pushed into service as a fighter during the Battle of Britain but it was not fast enough.Bowyer, Michael J. F. The Battle of Britain: The Fight for Survival in 1940. Manchester, UK: Crécy 2010. . Equipped with an early Airborne Interception (AI) radar set, however, it proved to be an effective night fighter.
First World War The first single-seat fighters to drop bombs were on the Western Front, when fighter patrols were issued with bombs and ordered to drop them at random if they met no German fighters. The Sopwith Camel, the most successful Allied aircraft of the First World War with 1,294 enemy aircraft downed, was losing its edge by 1918, especially over . During the final German offensive in March 1918, it dropped Cooper bombs on advancing columns: whilst puny by later standards, the four fragmentation bombs carried by a Camel could cause serious injuries to exposed troops. Pilot casualties were also high.Davis, Mick. Sopwith Aircraft; Crowood Press, Marlborough England, 1999 The Royal Aircraft Factory S.E.5. was used in the same role.
The Royal Flying Corps received the first purpose-built fighter-bomber just as the war was ending. It was not called a fighter bomber at the time, but a Trench Fighter as that was what it was designed to attack. The Sopwith Salamander was based on the Sopwith Snipe fighter but had armour plating in the nose to protect the pilot and fuel system from ground fire. Originally it was intended to have two machine guns jutting through the cockpit floor so as to spray trenches with bullets as it passed low overhead. But this did not work and it was fitted with four Cooper bombs, instead. It was ordered in very large numbers, but most were canceled after the Armistice.
In February and April 1918 the Royal Flying Corps conducted bombing tests at Orfordness, Suffolk dropping dummy bombs at various dive angles at a flag stuck into a shingle beach. Both WW1 fighter bombers were used with novice and experienced pilots. The best results were achieved with a vertical dive into the wind using the Aldis Sight to align the aircraft. But they were not considered good enough to justify the expected casualty rate.
Second World War
When war broke out in Europe, Western Allied Air Forces employed light twin-engined bombers in the tactical role for low-level attacks. These were found to be extremely vulnerable both to ground fire and to single-engine fighters. The German and Japanese Air Forces had chosen dive bombers which were similarly vulnerable. The Ilyushin Il-2 is a heavily armoured two-seat single-engine ground-attack aircraft. It first flew a month later although few had reached the Soviet Air Force in time for Operation Barbarossa. Naval forces chose both torpedo and dive bombers. None of these could be considered as fighter bombers as they could not combat fighters.
Germany
During the Battle of Britain, the Luftwaffe conducted fighter-bomber attacks on the United Kingdom from September to December 1940. A larger fighter-bomber campaign was conducted against the UK from March 1942 until June 1943. These operations were successful in tying down Allied resources at a relatively low cost to the Luftwaffe, but the British Government regarded the campaign as a nuisance given the small scale of the individual raids.
In August 1941, RAF pilots reported encountering a very fast radial engine fighter over France. First thought to be captured French Curtiss 75 Mohawks, they turned out to be Focke-Wulf Fw 190s, slightly faster and more heavily armed than the current Spitfire V. Kurt Tank had designed the aircraft when the Spitfire and Bf 109 were the fastest fighters flying; he called them racehorses, fast but fragile. As a former World War I cavalryman, Tank chose to design a warhorse. With a BMW 801 radial engine, wide-set undercarriage, and two 20mm cannons as well as machine guns it became a better fighter-bomber than either of the pure fighters.
By mid-1942, the first of these Jagdbomber (literally "fighter" or "hunter" bomber, known for short as "Jabos") was operating over Kent. On October 31, 60 Fw 190s bombed Canterbury with only one aircraft lost, killing 32 civilians and injuring 116, in the largest raid since the Blitz. Flying at sea level, under the radar, these raids were hard to intercept. The Jabos reached the Eastern Front in time to bomb Russian positions in Stalingrad.Bergstrom, Christer (2007). Stalingrad – The Air Battle: November 1942 – February 1943. London: Chevron/Ian Allan. By July 1943 Fw 190s were replacing the vulnerable Stukas over the Battle of Kursk: although winning the air war, they were unable to prevent subsequent Red Army advances.Bergström, Christer (2007). Kursk – The Air Battle: July 1943. London: Chevron/Ian Allan.
On New Year's Day 1945 in Operation Bodenplatte, over 1,000 aircraft (including more than 600 Fw 190s) launched a last-ditch attempt to destroy Allied planes on the ground in support of the Battle of the Bulge. Allied fighter aircraft and fighter-bomber losses were downplayed, at the time. Seventeen airfields were targeted, of which seven lost many aircraft. The surprise was complete as the few Ultra intercepts had not been understood. At the worst hit, the Canadian base at Eindhoven, 26 Typhoons and 6 Spitfires were destroyed and another 30 Typhoons damaged. In total, 305 aircraft, mostly fighters, and fighter-bombers were destroyed and another 190 damaged. The Luftwaffe lost 143 pilots killed, 71 captured and 20 wounded, making the worst one-day loss in its history; it never recovered.Manrho, John & Pütz, Ron. Bodenplatte: The Luftwaffe's Last Hope-The Attack on Allied Airfields, New Year's Day 1945. Ottringham, Yorkshire, United Kingdom. Hikoki Publications.
United Kingdom
The Bristol Blenheim and Douglas A-20 Havoc (which the RAF called Boston) were used as night fighters during the Blitz, as they could carry the heavy early airborne radars.Ray, John. The Night Blitz: 1940–1941. Cassell Military, London. 1996.
The Hawker Henley, a two-seat version of the Battle of Britain-winning Hawker Hurricane, was designed as a dive bomber. It might have proved to be a capable fighter-bomber but overheating of its Rolls-Royce Merlin engine in this installation led to its relegation to a target tug role, where it could match the speed of the German bombers whilst towing a drone.Mason, Francis K. Hawker Aircraft since 1920. Putnam. London 1991.
In 1934, the British Air Ministry called for a carrier aircraft that could combine the roles of the dive bomber and fighter, to save limited space on small carriers. The Blackburn Skua was not expected to encounter land-based fighters but was to intercept long-range bombers attacking the fleet and also to sink ships. As a two-seater, it could not fight the Messerschmitt Bf 109 on equal terms, but the second seat carried a radio operator with a homing device that could find the carrier even when it had moved, in foul North Sea weather. It achieved one of the first kills of the war, when three from HMS Ark Royal downed a German Dornier Do 18 flying boat over the North Sea.Beadle, Jeremy, and Harrison, Ian: Firsts, Lasts, and Onlys: Anova Books, 2008
On April 10, 1940, 16 Skuas operating from RNAS Hatston in Orkney under Commander William Lucy sank the German cruiser Königsberg which was tied to a mole in Bergen harbour. The Germans recorded five hits or near misses and as the ship started to sink, electric power failed, dooming the ship. The German cruiser Köln had departed during the night.Haar , Gerr H, The German attack on Norway April 1940. Seaforth, Barnsley. England 2009.
With the failing of the Hawker Henley and the gradual fading of the Hawker Hurricane's performance compared to the latest German fighters, it was modified to carry four 20mm cannon and two bombs; once bombs were jettisoned the aircraft could put up a reasonable fight. Inevitably the type became known in the RAF as the “Hurribomber”, reaching squadrons in June 1941.Dibbs, John and Tony Holmes. Hurricane: A Fighter Legend. Oxford, UK: Osprey, 1995.