The propellers of WWII planes were significantly more advanced than those of previous generations. Variable-pitch propellers, developed in the late 1930s, increased the efficiency of the propeller blades at different speeds. The number of blades had also been increased since WWI, adding to a plane’s power.
Flyers Over Poland
During the invasion of Poland, the Germans had better fighter aircraft and more of them. The Polish air force still put up a valiant struggle. The pilots of their best fighter, the PZL P.11, destroyed 126 Luftwaffe aircraft.
Fighters Over Britain
The number of fighters in the Battle of Britain was surprisingly small, given the enormous significance of the battle. At the start, the RAF had 600 front-line fighters, the Germans 1,200. Both sides churned out replacements as quickly as they could, but it was difficult to keep up with the losses. Pilots were even more difficult to replace than planes.
Flying Around the Clock
In mid-September 1940, at the height of the Battle of Britain, the RAF’s fighters were in almost constant use. Each one was flown several times a day, every day, wearing out the machines and exhausting the pilots.
At the start of the war, no nation had radar fitted in their planes. Aiming by sight, it was hard to attack enemy aircraft at night.
The British were the first to deploy airborne radar on a night fighter successfully. In late July 1940, a Bristol Blenheim IF shot down a German Dornier Do 17 during a night attack, using radar for targeting. The Blenheim, unable to match the Germans in daylight, had found a new use.
The first high-performance purpose-built night fighter followed. It was the Bristol Beaufighter, equipped with a devastating array of four cannons and six machine-guns.
Self-sealing Fuel Tanks
The Germans fitted many of their planes with self-sealing fuel tanks. They were made with light-weight metal covered in layers of vulcanized and non-vulcanised rubber. If shrapnel or a bullet pierced the fuel tank, then the leaking fuel would make the non-vulcanised rubber expand, sealing the gap. Many aircraft and their pilots were saved from a fiery end by those tanks. Planes the Allies recorded as “probably destroyed” managing to limp back to their base.
Electric Reflector Sights
WWII saw the introduction of electric reflector sights, the predecessors of modern head-up displays. A circle of light on a small glass screen replaced simple ring-bead sights, allowing pilots to aim better while retaining situational awareness.
The Deadly Zero
The Mitsubishi Zero was the primary fighter used by the Japanese to protect their bombers in the Pacific. Its excellent maneuverability made it a challenging opponent.
That maneuverability was at a price. Everything that could be done to reduce its weight was. No armor protected the pilot, and some did not carry radios.
The War-Winning Carrier Fighter
The decisive fighter in the Pacific was the Grumman F6F Hellcat. Hurried into production to counter the Japanese, it first arrived in the war zone in August 1943. The tough fighter was capable at all altitudes and was a game-changer in the Pacific.
The F6F’s first major air battle took place on December 4, 1943. On that day, Hellcats destroyed 28 Zeros, losing only two planes. The tables had been turned on the Zero. Over 300 pilots became aces, destroying five or more enemy aircraft while flying the Hellcat.
The Ever-Changing Spitfire
Perhaps the most famous plane of the war, the Spitfire was the symbol of British superiority during the Battle of Britain. Although not able to climb as fast as some German planes, the Spitfire was the most maneuverable plane in the air. With its eight machine-guns, it also had the firepower to take down opponents.
The Spitfires that won the Battle of Britain were mainly Mk Is, with some Mk IIs. The plane continued to evolve throughout the war. By late 1944, Mk XIVs were in action, carrying out the heaviest fighter-bomber raid of the war.
Spitfires served all over the world, from Russia to Africa to the air defenses of Australia.
The higher speed of WWII fighters meant parachutes became increasingly insufficient in providing an escape from a damaged aircraft. The Germans responded by developing compressed air ejector seats first fitted to the Heinkel He219A-0.
The first pilot to have his life saved by an ejector seat was Flugkapitan Otto Schenk. During a test flight in January 1942, he lost control of his Heinkel jet but survived after ejecting.
Machine-guns Versus Cannons
Many planes, such as the first Spitfires, were equipped with multiple machine-guns. As the war progressed, improved aircraft armor and advances such as the self-sealing fuel tank meant heavier firepower was needed. Manufacturers moved toward fitting planes with cannons that fired exploding shells.
There was a balancing act in deciding which to use. The Messerschmitt Bf109’s cannon could fire five explosive shells a second. The Hurricane’s eight machine-guns could shoot 160 bullets in the same amount of time. It was a choice between quantity and quality. The British compromised, fitting later Hurricanes and Spitfires with mixed weapons.
By the end of the war, some planes had been equipped with air-to-air missiles. They were much less sophisticated than those that followed, lacking guidance systems to bring them in on their target. The warheads were typically impact-fused, meaning that a direct hit was needed.
Although crude, the missiles could be deadly. Late in the war, Luftwaffe fighters were often equipped with 24 missiles which were a deadly menace when fired as a salvo.
Towards the end of the war, both sides fielded early jet fighters. Their more powerful engines gave them better speed than their propeller-driven predecessors. The P-51 Mustang had a top speed of 437mph, while the Messerschmitt Me262 managed 540mph.
Nigel Cawthorne (2004), Turning the Tide: Decisive Battles of the Second World War
Francis Crosby (2010), The Complete Guide to Fighters & Bombers of the World