By the end of the war military aircraft had advanced at an astonishing rate from basic fighters to complex warplanes designed to control the air space, defend formations of bombers, destroy land based targets and support the fleet. In every theatre of operations Europe, the Pacific and the Eastern Front engineers relentlessly improved engines, aerodynamics, weapons, armour and range as flights of increasingly technologically advanced aircraft found themselves in ever more dangerous encounters. The result was combat aircraft which not only reflected the technologies of their country of origin but became as much icons of nations as their pilots.

Cut through the noise of illustrious icons and war mythologies and you’ll find that the best aircraft weren’t always the fastest or the most heavily armed. Combat effectiveness was a delicate equation, with the best aircraft being fast and reliable, manoeuvrable and robust, possessing a good range, capable of large-scale production and, ideally, flown by well-trained pilots. This list takes a look at ten of the most important piston-engined aircraft of the war, spotlighting their engineering features, combat utility and their legacy.

1. Mitsubishi A6M Zero

The Japanese Zero aircraft was used during the diverse simultaneous military strikes on Pearl Harbour, Guam, Midway Island and Philippines in December 1942. Weighing only 2.7 tons, the fighter aircraft of 950 horsepower could reach 331 mph and climbs to 32,810ft service ceiling and many pilots were initially presented with the challenge of taking on the high inertia, great climbing advantage and high manouverability that the Zero offered the aviation forces of the Japanese. The aircraft was built by Mitsubishi Heavy Industries and designed by Jiro Horikoshi.

The Zero’s Early Combat Strengths:

• 950-horsepower engine
• 331 mph top speed
• 32,810-foot service ceiling
• Highly manoeuvrable design
• 10,939 aircraft produced

The balance of power shifted in 1942, when a crashed Zero was recovered from a Pacific island and sent to the US for analysis. The engineers quickly identified the aircraft was unarmoured and had non-pressurised carbs which tended to cause the engine to cut out on dives at steep angles. US pilots learned to use this against the Zeros, baiting them into a steep dive and then taking them on with the help of cheap ageing American equipment and tactics. Though it was still a dangerous aircraft in 1944, its speed had fallen behind that of the US Navy’s fighters, though an experienced pilot could still make the most of it.

2. Focke-Wulf Fw 190

The Focke-Wulf Fw 190 entered service in 1940 and became one of the most heavily produced German fighters that became a formidable challenge to the initial British Supermarine Spitfire aircraft. With turbo and supercharged BMW 801 radial engine that produced 1,776hp, and was able to reach a speed of 426mph, the Fw 190 was faster and nimbler and more difficult to confront in the early phases of aerial combat throughout Europe. The aircraft was designed by Kurt Tank and saw much combat service during World War 2.

Why The Fw 190 Was So Effective:

• 1,776-horsepower BMW 801
• 426 mph top speed
• Strong low-altitude performance
• Highly versatile combat aircraft
• More than 20,000 built

The Fw 190’s versatility proved to be useful beyond dogfighting, since it was also capable of ground attack and bombing roles. Its twin-row BMW 801 radial engine gave it the capacity for heavier load loads than the single engine Messerschmitt Bf 109, making it capable as a day fighter, fighter-bomber, ground-attack aircraft, and, to a more limited extent, as a night fighter. Efforts to improve high-altitude performance evolved into the Ta 152. These efforts came to late to turn the tide of the war, and fuel and materials shortages severely limited Luftwaffe operations.

3. Curtiss P-40

The P-40 was originally developed to a number of different design contracts placed by the United States Army in the 1930s, and in service with different names Warhawk, Tomahawk or Kittyhawk according to its operational type. Outwardly a product of the mid-1930s fighter airframe concept the P-40 had a reputation for toughness which exceeded that of any of its contemporaries. 13738 P-40s were manufactured; it was the third most-produced American fighter of World War II.

The P-40’s Greatest Strengths:

• Extremely rugged airframe
• 13,738 aircraft produced
• Served across multiple theatres
• Survived substantial enemy fire
• Strong combat durability

It was heavily used in the Burma, China, India areas as well as in North Africa and elsewhere. P-40 pilots flying in China with the American Volunteer Group were credited with nearly 300 kills with only 12 lost. It was a tough airplane and could take heavy punishment and still live through the fierce aerial battles of the early-war time period. Since its lack of a two-stage supercharger was at a disadvantage against aircraft such as the Bf 109 and the Fw 190 when flying at high altitude, it wasn’t quite as good in the bomber escort role when fighting at these altitudes, and the airplane still proved to be a decent air-superiority fighter, bomber escort, and fighter-bomber.

4. Republic P-47 Thunderbolt

The Republic P-47 Thunderbolt, the heaviest single-engined fighter ever used in WW II, was highly versatile in its various roles. Powered by an immense 2,000-horsepower Pratt & Whitney R-2800 Double Wasp radial engine and turbocharger, this plane could reach speeds of up to 426 mph at high altitudes. Eight.50-calibre machine guns packed a punch, and the plane’s built-in strength meant it could still fly even when damaged in combat.

The Thunderbolt’s Powerful Formula:

• 2,000-horsepower radial engine
• 426 mph high-altitude speed
• Eight .50-calibre machine guns
• 15,636 aircraft produced
• Exceptional structural durability

American factories constructed 15,636 P-47s, more than any other American wartime fighter. In addition to shooting down more than 7,000 enemy aircraft in the air, the Thunderbolt proved an extremely capable ground-attack aircraft and dive bomber. Its rugged construction saved the lives of many pilots, and the airplane destroyed thousands of railway cars, locomotives, armoured vehicles and trucks in Europe’s war zones. It was able to escort American bombers deep into Germany before turning back to the target to attack ground targets on the return trip. Its ability to operate at high altitudes, combined with its firepower and durability, made it one of America’s most important fighters of the war.

5. Grumman F6F Hellcat

The Grumman F6F Hellcat the ‘ace of the Pacific war’ This aircraft was introduced into service in late 1943 with design drawing experience from the Battle of Britain, and a major expansion followed. As a carrier-based fighter it was fitted with a 2,000-hp. Pratt & Whitney Double Wasp radial engine and up to six.50-calibre machine guns. American manufacturers created 12,275 of these aircraft, most of them (11,000) during two years alone.

The Hellcat’s Pacific Impact:

• Entered service in 1943
• 2,000-horsepower radial engine
• Six .50-calibre cannons
• 12,275 aircraft produced
• Outperformed the A6M Zero

The Hellcat revolutionised aerial combat in the Pacific by providing American pilots with a warplane capable of taking on the Japanese Zero fighters on more or less equal terms. It proved to be a tough aircraft with sound aerodynamic qualities and a sturdy carrier design and quickly became the US Navy’s primary warplane for the second half of the Pacific war. In the Battle of Leyte Gulf, Captain David McCampbell shot down 15 Japanese aircraft in one sortie, then returned to his carrier with empty fuel tanks and jammed guns. Despite entering the war late, the Hellcat was responsible for the destruction of 5,223 Japanese aircraft with the US Navy, US Marine Corps and Royal Navy Fleet Air Arm.

6. Ilyushin Il-2

The Soviet industrial solution was to develop one of the most devastating aerial platforms of the Second World War the Il-2. Stalin wanted his aircraft to be a “flying tank”, and the aircraft was designed for mass production and tough construction while also having a specific ground-attack role. It was powered by a 1,770-horsepower V12 engine and could attain a top speed of 258mph.

The Il-2’s Armoured Ground Role:

• 1,770-horsepower V12 engine
• 258 mph top speed
• Heavily armoured fuselage
• Rear gunner added protection
• 36,183 aircraft produced

Post World WarII History Despite its relatively slow speed in comparison to other fighters of its time, the Il-2 proved to be a pivotal element of the air war on the Eastern Front. The heavily armoured fuselage enabled fighters to stand up to frequent fuselage hits from anti-aircraft fire, making it well suited to the attack role in which it was expected to fulfil. Soviet factories turned out 36,183 of the aircraft which, according to the information provided, makes it the most widely produced military aircraft design in history, providing the backbone of the Red Air Force while inundating the enemy.

7. Messerschmitt Bf 109

The fighter plane was the mainstay of the WWII-era German Luftwaffe. Built first in 1935, it assisted the Wehrmacht in its 1939 invasion of Poland. The aircraft initially was powered by a 675-horsepower Junkers engine and could reach a top speed of 250 mph, but later versions were equipped with a much more powerful 1,850-horsepower inverted V12 Mercedes-Benz engine capable of speeds of 426 mph at high altitude.

The Bf 109’s Long Combat Career:

• First flew in 1935
• Early engine produced 675 horsepower
• Later engine reached 1,850 horsepower
• High-altitude speed reached 426 mph
• Around 34,000 aircraft produced

Thanks to the Bf 109’s high speed and high altitude performance, it proved a serious threat to the Allied forces, from the Battle of Britain to the final days of the Third Reich. An estimated 34,000 Bf 109s were made, which, as far as the given information states, makes the aircraft the most produced fighter ever. It was flown by some of the highest scoring aces ever, notably, Erich Hartmann, who was credited with 352 total victories over 1,404 missions without being shot down by the enemy. The Bf 109 was constantly in development and was able to go toe to toe with the latest Allied fighters until the end of the war, as well as being adapted to a variety of roles such as the bomber escort, fighter-bomber, reconnaissance and ground attack.

8. Hawker Hurricane

Hawker Hurricane The most important aircraft to defend Britain’s skies in the desperate summer of 1940. At the start of the Battle of Britain, 620 Hurricanes and Spitfires took on a German fleet of more than 3,500 fighters and bombers. The Hurricane was the first British fighter to top 300 mph with the legendary Rolls-Royce Merlin engine, and went on to achieve 327 mph in its Mk II variant.

The Hurricane’s Defensive Strengths:

• Rolls-Royce Merlin engine
• First British fighter beyond 300mph
• 327 mph Mk II speed
• Exceptional durability
• More than 14,000 built

Despite having engines that produced more horsepower and a greater speed, Hawker’s Hurricane was used to its full potential by the skilled British pilots in the strength and smooth operating high firing gun platform. The Hurricane shot down the majority of the aircraft during the Battle of Britain, and more than 14,000 were built, primarily as a defensive weapon during the difficult early months of the war. The Hurricane also became bomber interceptors, fighter-bombers, and support aircraft to ground troops, while specialized Sea Hurricanes were modified for ship use. Its practicality meant that it was an important aircraft during much of the conflict.

9. Supermarine Spitfire

The Spitfire one of the most widely recognised aircraft of all time was central to Britain’s defence efforts in the war thanks to its beautiful design, in particular the elliptical wings. The Spitfire first took flight in 1936 and used a sophisticated monocoque construction in which the skin itself contributed to the strength of the structure. Originally powered by Rolls-Royce Merlin engines and armed with 4 guns per wing, the Spitfire became a match for the Germans over the English Channel.

The Spitfire’s Evolutionary Performance:

• Distinctive elliptical wing design
• Rolls-Royce Merlin power
• More than 20,351 built
• Late Griffon engines reached 2,000hp
• 443 mph late-war speed

Throughout the war, engineering designs on the Spitfire were continuously being refined and improved, until the late-war versions were being fitted with 2,000-horsepower Rolls-Royce Griffon engines capable of 443-mph. The combination of manoeuverability and heavy cannon-firepower allowed the Spitfire to adapt to changing aerial threats throughout the war. It also became the most adaptable and versatile of wartime aircraft, serving as an interceptor, photo-reconnaissance plane, fighter-bomber and trainer. It was the only British fighter to be produced throughout the entire war, and after the Battle of Britain became the main aircraft of the RAF Fighter Command. Its adaptability even allowed it to become the first Allied propeller-driven fighter aircraft to shoot down a German jet-powered Me262.

10. North American P-51 Mustang

The North American P-51 Mustang has earned itself the reputation as the ultimate fighter aircraft design of the second World War. It was the fastest of its type to be built, though a dog sluggish initially with American produced engines, although the advent of its fuselage with the British Rolls-Royce Merlin power plant achieved phenomenal capability and mass licence production at the Packard Motor Car Company.

The Mustang’s Long-Range Advantage:

• Prototype built in 117 days
• Rolls-Royce Merlin transformed performance
• 437 mph operating speed
• 1,000-mile escort range
• 4,950 enemy aircraft claimed

Introduced in US service in 1943, the long-range P-51D could escort US bombers for up to 1,000 miles deep into enemy territory. Reaching 437 mph in level flight at 41,900 ft, the Mustang soon established air superiority over Europe, where Mustang pilots would log a total of 4,950 ground-attack kills, the most of any US fighter. Its ability to fly deep into enemy territory on high-octane piston power, combined with its capability to operate at very high altitudes with its Merlin engine, made the long-range fighter nearly unstoppable. The P-51 later served into the Korean War, known as the F-51, before jet fighters replaced it in US service and it was flown by civilian warbird enthusiasts and air racers.