Blog | The Majestic 'Merlin': How An Engine Helped Britain Win World War 2

"Never in the field of human conflict was so much been owed by so many to so few"
- Winston Churchill, in his tribute to pilots who fought the Battle of Britain

On June 23, 1940, Adolf Hitler and his Nazi entourage stood in front of the Eiffel Tower for a picture (below), marking one of the most defining moments of World War II. France fell to the Nazis and its government signed an armistice agreement following a surrender. The Blitzkrieg campaign by Nazi forces that had taken over Poland, Belgium and the Netherlands in just six months also managed to bring France to its knees.

The war was at a critical juncture. On France's west, across the English Channel, lay the United Kingdom under Prime Minister Winston Churchill, who refused Hitler's truce offer. "We stand as the last bastion against the menace of tyranny," said Churchill after the fall of its neighbour and strongest ally in Europe. Initially, the Germans made no plans to invade Britain; Hitler was counting on his country's military supremacy and strong industrial network to sustain the war. But the relative calm couldn't last long, and in July, he ordered the execution of 'Operation Sea Lion' for the invasion of Britain.

The Battle Of Britain

The Royal Navy was one of the most formidable forces in the world, a wing that helped Britain extend and sustain its global colonial presence. An invasion of the country would require a coordinated sea and air attack before a ground capture. And so, the Luftwaffe, that is, the German Air Force, began its bombing campaign. The objective was to render the Royal Air Force (RAF) defenceless and make a sea operation possible. The Battle for Britain had begun. 

The attack on British convoys and ports was only the beginning. The first major and concentrated offensive against the RAF, called the 'Adlerangriff', or the Eagle Attack, came in August, in which the German Stuka bombers and the mighty Messerschmitt Bf.109 unleashed their relentless bombing. What formed the aerial bulwark against them were the RAF's Supermarine Spitfires and Hawker Hurricanes in Britain, and the P-51 Mustangs, Fairey Battles, and Lancasters in other theatres. Termed as the "arsenal of democracy" for an air war, they all had one thing in common: a mass-produced, supremely efficient Rolls-Royce engine.

Introducing.... The 'Merlin'

Rolls-Royce, which was largely known for its car engines until then, decided in the 1930s to develop high-output engines. The Air Ministry in 1935 issued a notification for building a new fighter aircraft that would be fast, manoeuvrable, and had four machine guns. Britain's two main aerial fighters against the Luftwaffe, the Spitfire and the Hurricane, were both powered by the V12 Rolls-Royce piston engine, a.k.a. 'Merlin'. The engine was a V12 (12 pistons) liquid-cooled aero machine that had a capacity of 27 litres. Like all Rolls-Royce aero engines, the 'Merlin' was named after a bird of prey. But it also evoked the spirit of King Arthur's famous wizard. To the pilots who relied on it, the Merlin really did seem magical.

Initially, the 'Merlin' provided approximately 900 horsepower, but by the end of the war in 1945, it had been developed further and was powering the de Havilland Hornet, a twin-engine bomber in which each 'Merlin' produced over 2,000 horsepower with a supercharge. Being quite a reliable engine, it was mass-produced during the war after Rolls-Royce allowed America's Packard to manufacture it under a licence. As many as 55,000 Merlins were produced between 1942 and 1945. The collaboration proved to be crucial, especially when British cities became targets of night bombings and industrial production was hit badly. By the end of the war, around 1.5 lakh such engines had been produced to fight the Axis powers. The American P-51 too, later called the 'Mustang', was equipped with the Merlin. At the Imperial War Museum (IWM) in London, a volunteer in fact told me that the Merlin became so popular that many years after the war, a man in the UK put it in his car and called it 'The Beast'.

Killing Machines

However, IWM expert Graham Rodgers points to a drawback in the engine that in some cases became the Achilles Heel of the Spitfires and the Hurricanes. The aircraft couldn't perform a negative 'G-dive' against Germany's Messerschmitt 109 as its "carburettors would get flooded with oil and the engine would cough up during a dogfight", Rodgers explains in a video. 

Nonetheless, the Spitfires and the Hurricanes together held out and shot down 1,733 German planes against 913 of their losses - though the former with 32 squadrons was numerically superior to the Spitfire, which had only 19 squadrons in Britain. The 'Merlin' could power the Hurricanes to a speed of 480 km/hr, the first RAF fighter that could do so. Over half of the enemy planes were shot down by the Hurricane, not the Spitfire.

The Lost Indian Tale

The Hurricane was the only RAF aircraft that was deployed in every theatre of war. One of them was India, where it was tasked to conduct operations in Burma.

Out of the nine Indian Air Force squadrons that witnessed action during World War II, eight were equipped with Hurricanes. Spitfires made appearances too, but Hawkers were deployed in larger numbers in the eastern theatre.

The Forgotten Few: The Indian Air Force in World War II by K.S. Nair documents the less-recognised contributions of the IAF during the Second World War. Squadron Leader - then Pilot Officer - Mohinder Singh Pujji, one of the first Sikh pilots who served in the RAF and later the Indian Air Force, flew the Spitfires and Hurricanes in France, Burma and the Middle East.

He was even awarded the Distinguished Flying Cross (DFC) for his reconnaissance operation over the Japanese-occupied territory. 

Another officer, Flying Officer Jagadish Chandra Verma, shot down a Japanese 'Oscar' and gave the IAF its first kill in Burma. He was immediately honoured with the DFC for prevailing over a superior Oscar with his Hurricane. 

(Divyam Sharma is a Senior Sub Editor at NDTV)

Disclaimer: These are the personal opinions of the author.