At the start of 1939, the United States Army Air Corps wanted more of its favourite aircraft, the B-17 Flying Fortress. Consolidated took one look at the B-17 and decided they could do better. They responded with a proposal for a new aircraft which could fly faster, further, higher, and carry more bombs.

The United States Army Air Corps could hardly refuse, and the prototype took flight in December 1939. Named for the role it was intended to play in the war to come, the aircraft would play a key role in America’s bombing effort around the world and become the most produced military aircraft of all time. The B-24 Liberator. In this video, Emily Charles walks us through the history and technical aspects of this iconic aircraft.

The B-24 Liberator


Emily Charles, Curator, American Air Museum:  "At the start of 1939, the United States Army Air Corps wanted more of its favourite aircraft, the B-17 Flying Fortress.

The development of heavy bombers in the 1930s had led American commanders to adopt a doctrine of high altitude precision bombing that was intended to maximize devastation.

They believed aerial bombardment was a war winning tool, and with conflict looming on the horizon, they needed more aircraft. So the US Army Air Corps approached Consolidated with a request
to build the B-17 under license.

Consolidated took one look at the aircraft and decided they could do better. They responded with a proposal for a new aircraft which would fly faster, higher, further and carry more bombs.

The US Army Air Corps could hardly refuse, and the prototype took flight in December 1939. Named for its intended role in the war to come, the aircraft would play a key part in America's bombing effort around the world, becoming the most produced military aircraft of all time, the B-24 Liberator. 

In the 1930s, Consolidated was known more for making flying boats than bombers, and their counter offer to the US Army Air Corps took full advantage of signature seaplane features. To land on water, a plane's critical flight components like the wings, tail and engines need to be kept high, while the fuselage needs to be deep and buoyant to help the aircraft float.

These concepts are all visible in the B-24. Consolidated repurposed the big boxy fuselage into a bomb bay, which could take a huge bomb load of up to 8,000 pounds.

The bomb bay doors also opened up by rolling inside the aircraft, which reduced drag in flight. The high shoulder mounted wings also increased the capacity of the bomb load and the speed of the aircraft. The design was the brainchild of Consolidated Engineer David Davis, who invented a laminar flow, a wing, where the air flows smoothly over the surface without generating turbulence. And this is before the science of laminar flow was fully understood.

The design of the Davis wing was long and narrow, which generated less drag and more speed and lift. It was also unusually thick, particularly on its leading edge being designed to support the liberator for engines and carry their fuel. Though a flying boat was the starting point for its design, the Liberator proved truly terrible at landing on water.

The aircraft was so prone to sinking that crew survival rates after ditching were worryingly low. British and American forces both attempted to solve this problem with some success by reinforcing the bomb bay but concluded only a complete redesign would make the B-24 less sinkable.

The first B-24s were not flown by the Americans, but by the British. Already at war with Germany and wanting to strengthen their bomber forces, Britain and France placed orders for the B-24 before the prototype was even completed. But France had surrendered by the time the production run was complete. So that order was transferred to the RAF, who received the first models in March 1941.

The B-24 was designed to be a heavy bomber, but its deep fuselage and long range lent itself to adaptation to other roles. The RAF used its first Liberators to transport pilots between the US and the UK, but adapted its next allocation for use by RAF Coastal Command.

As an island nation, Britain needed supplies from the US and its empire to support the war effort. But shipping was threatened by German U-boats which could operate beyond the range of aircraft in an area known as the mid-Atlantic Gap. The modified very long range Liberators were the first RAF aircraft with the range to protect convoys crossing the Atlantic. Fitted with U-boat detecting radar and the ability to launch surprise air attacks, the VLR Liberator could hunt for German submarines trying to starve the UK."

Collections footage: "Coastal aircrafts fly at relatively low altitude, usually between 1000 and 1500 feet. The bombing level is normally 50 feet. The depth charges are aimed so as to straddle the U-boat. Their lethal range is 19 feet and they are set to explode at a 25 foot depth."

Terence Malcolm Bulloch: "We didn't get many Liberators. In fact, we started with about four. The Americans were so niggly they wouldn't let us have any more. And eventually we got up to ten and the squadron became operational at the end of 41. And from then until early in 43, we were the only long range VLR, which are very long range, Liberator squadron in the Royal Air Force."

Emily Charles: "The arrival of these aircraft in increasing numbers helped the Allies to close the Mid Atlantic Gap and minimize the U-boat threat. By 1943, the Battle of the Atlantic was all but won. After the US joined
the Second World War in December of 1941, American Liberators began to see service around the world.

The 44th bomb group equipped with B-24 Liberators were the first to arrive in Britain in September 1942. They would form a key part of the allied strategic bombing campaign against Nazi Germany. Alongside the B-17 Flying Fortress, the B-24 Liberator was flown from British, North African and later Italian bases to bomb industrial, military and economic targets in German occupied Europe.

Statistically speaking, it was one of the most dangerous postings of the Second World War. The most famous B-24 raid of the Second World War took place on the 1st of August 1943, Operation
Tidal Wave. A force of 177 Liberators set out from bases in North Africa to bomb axis oil refineries in Romania. Nazi Germany was already short on fuel and the US Army Air Force's belief that by destroying Ploiești, they could severely weaken their enemies.

However, the operation proved to be a resounding failure and one of the bloodiest allied air raids of the whole war. 53 Liberators were lost and around 660 airmen were killed, captured or interned. And there was ultimately no impact on oil production. The B-24 served in huge numbers. By the summer of 1944, almost half of the U.S. Army Air Force's bomber strength in Europe was made up of B-24s, with many serving
under the 15th Air Force in Italy and the second Air Division of the eighth Air Force in Britain.

The Allies' ability to produce and maintain equipment in huge quantities was vitally important to their eventual victory. The B-24, built at five plants across the US serves as an excellent example of this. The largest factory; the mile long Ford production line at Willow Run in Detroit. In total, around 19,000 Liberators were built between 1940 and 1945, the most of any bomber ever.

Around a third of those, including the one behind me, were built at Willow Run. Given it's service history, the B-24 Liberator should have emerged as one of the most successful and famous bombers of its day. But ultimately, with its boxy appearance, it was never quite as popular as the more streamlined B-17.

While it could fly faster, further, and with a greater bomb load, the Liberator was more difficult to control and gained a reputation as a dangerous aircraft."

Terence Malcolm Bulloch: "Well, I'd never seen an airplane as big as that before. It had four very powerful engines. It was very impressive to look at with the twin tail. It was quite different from the flying Fortress. It was more difficult to fly and was heavier on the controls."

Emily Charles: "In 1943, the aircraft became known as the so-called 'problem plane' because of how frequently it was involved in accidents during training. We can attribute this problem more to inexperienced pilots and insufficient training rather than the Liberator itself, as the overall accident rate proved to be very similar to that of the B-17. B-24 accidents did, however, lead to more fatalities than B-17 ones, both in training and in battle.

There was a belief that the B-17 could withstand greater battle damage in combat than the B-24. While this claim is hard to prove, there is certainly more photographic evidence of B-17s that managed to limp home with extreme battle damage, as well as many dramatic images of stricken B-24s exploding in mid-air.

What perhaps is more likely is that the B-17 was more escape-able. Escape hatches on both aircrafts were in roughly the same place, but with the radio operator, engineer and two pilots crowded into the flight deck, these crewmen had to squeeze past each other to get in and out of the aircraft through the bomb bay, creating a bottleneck in the B-24, which just didn't exist in the B-17. Design also made a difference. The lower mounted wing on a B-17 helped the fuselage to absorb the shock of a crash landing while the shoulder mounted Davis wing on the B-24 placed a lot of weight on the fuselage, which in a heavy landing caused it to crumple.

There are instances when pilots managed to land their Liberator, only for them to be killed and crushed
by the top turret, landing upon them. Overall, for the bomber crews tasked with flying either aircraft in combat during the Second World War, there was not much notable difference in terms of safety or survivability. Like in a B-17, flying conditions inside a B-24 were cramped, cold and noisy while the aircraft itself offered little protection from enemy flak and fire.

The life expectancy of a bomber crewman was determined more by when their mission was taking place, especially the availability of long range fighter escorts and whether the Allies had achieved aerial superiority at the time more than the type of bomber that they were flying in. Ultimately neither the B-17 nor the B-24 proved up to the task of delivering victory through aerial bombardment alone and thousands of men lost their lives in the skies over Europe, executing the flawed doctrine of strategic bombardment.

When the Second World War ended, the B-24 was considered surplus to requirements by the U.S. Army Air Forces, outclassed by faster, heavier nuclear capable bombers like the B-29 Superfortress, B-24
Liberators were scrapped in large numbers.

This aircraft is one of only 13 surviving B-24 Airframes. It was used for scientific research until 1956, then spent 43 years on the edge of the parade ground at Lackland Air Force Base in Texas.

IWM disassembled this aircraft and shipped it to Duxford in 1999 where it was restored externally and it's been on display in the American Museum since 2001.

Most B-24 survivors, however, owe their existence to the Indian Air Force, which was the last military force
to fly the B-24 Liberator. At the end of the war, the US left around 70 B-24s to the RAF in India, who disabled them and dumped them at Kanpur Airfield. When war broke out between the newly independent nations of India and Pakistan in 1947, the Indian Air Force recovered and restored around 50 of these aircraft to flying condition. They kept them in operation through repair and salvage until 1968.

The B-24 has largely been forgotten compared to the fame of the B-17, but it can lay claim to most of the accolades the B-17 is now remembered for, including the famous Memphis Bell. It was actually a B-24
Liberator called Hot Stuff that was the first aircraft to complete 25 combat missions over Nazi occupied Europe, and it achieved this feat in February 1943, three and a half months before the Memphis Bell. Unfortunately, Hot Stuff crashed in Iceland on its return flight to the US, killing 14 of the 15 men on board. The US War Department decided Memphis Bell should therefore be celebrated as the first aircraft to survive 25 missions.

Despite its appearance and reputation, the B-24 was a cornerstone of Allied victory during the Second World War and its exploits and crews should not be forgotten.

Related content

B-17 video thumbnail
Second World War

B-17 Flying Fortress

The Boeing B-17 Flying Fortress dropped more bombs than any other US aircraft in the Second World War. A lot of these aircraft flew out of bases in England, as part of the USAAF’s daylight strategic bombing campaign. In this video, we take a close look at the B-17, take a look inside the fuselage and cockpit, and hear from two veteran B-17 crew.

Close up of P-47 Thunderbolt in flight.
© US Official Photograph (K4249)
Second World War

Why did US pilots love the Thunderbolt so much?

The P-47 Thunderbolt is one of the most recognisable US fighter planes from the Second World War. After the United States joined the war, pilots from the US Army Air Force were sent to Britain to aid in the war effort, along with their trusty Thunderbolts. In this video, our expert Graham Rodgers walks us through the history and technical aspects of this iconic aircraft.

Four Gloster Meteor aircraft in flight
Second World War

Gloster Meteor: The only Allied jet fighter of the Second World War

The Gloster Meteor was the RAF’s first jet fighter, bringing Britain into the Jet Age. At the same time, engineers of the German Luftwaffe had been working on developing their own operational jet fighter, and the Messerschmitt Me 262 entered service a few months before the Meteor. In this video, our expert Liam Shaw takes us around the details of the Gloster Meteor and its pioneering history.