De Havilland Mosquito

The Wooden Wonder

The British de Havilland Mosquito is one of those World War II warplanes that don't have the star allure of the P-51 Mustang or the Supermarine Spitfire, but which were excellent and important assets, nevertheless. Originally designed as a fast bomber, it grew into and excelled at a wide range of roles from reconnaissance plane through night fighter to maritime strike. It's probably best known, however, not for its speed, maneuverability or proven track record, but the fact that it was made of wood.

The British Air Ministry put out a call for a new twin-engine medium bomber design in September 1936. Most of the entries followed the design sensibilities typical at the time: heavy, metal-skinned planes protected by numerous guns in turrets. The Avro Manchester and the Handley Page Halifax (which ended up being a four-engine heavy bomber) had their inception with this call. George Volkert, chief designer at Handley Page, took a different approach and proposed an unarmed bomber that was fast enough to simply avoid enemy interceptors. The idea gained some traction within the Royal Air Force (RAF) and the Air Ministry, but was eventually discarded at the time on the grounds that while Volkert's design was faster than German planes at the time, it might have ended up being slower than the next generation of German fighters.

Another fan of the fast bomber concept was Geoffrey de Havilland, founder of the de Havilland Aircraft Company, who already had experience building high-speed racers and airliners, such as the DH.91 Albatross which pioneered the use of composite wood. De Havilland argued that a plane largely built of wood would not only be light and therefore fast, but would also free up aluminum and steel for use elsewhere. Additionally, parts could be built by woodworkers, furniture companies and piano workshops, allowing them to participate in the war effort. The lack of turrets on the fast wooden plane also meant that the bomber only needed a crew of two: a pilot and a navigator, seated side by side.

Freeman was convinced, but the Air Ministry wasn't, and de Havilland was asked to build wings for other bombers instead. Undaunted, de Havilland had his company continue working on the DH.98, the design that became the Mosquito, as a private venture.

In December 1939, with the war already raging, the Air Officer Commander-in-Chief of RAF Bomber Command still insisted that a bomber without guns was unacceptable, but agreed that the design might be good as a photo-reconnaissance plane. With Air Marshal Freeman's support, a contract for 50 "bomber-reconnaissance" versions was finally placed in March 1940. Two months later, the Air Ministry put out a new call for designs, this time for a long-range fighter armed with four .303 caliber machine guns and four 20 mm cannons. The DH.98 was quite ready to accommodate the guns in the nose, as well as an aircraft interception radar which allowed it to serve both as a day and night fighter.

Later that month, Nazi Germany overran France, leading to the evacuation of British troops at Dunkirk (The "Miracle of Dunkirk) and the looming threat of a German invasion (The Sea Lion That Sank). Lord Beaverbrook, the Minister of Aircraft Production, decided to concentrate on the building of interceptors that would be needed for the defense of Britain, and shut down other projects, including the Mosquito. He told Freeman to stop work on the wooden plane, but he failed to produce an actual written order specifically stating the directive; Freeman decided to just ignore him and continue. Beaverbrook fixed his oversight and issued an actual proper order in June 1940, and work on the Mosquito stopped... for less than a month. De Havilland's general manager promised Beaverbrook to produce 50 Mosquitoes by the end of the next year. The minister relented and development continued, even though only 20 of the promised 50 planes were ready by the end of 1941, as a third of the factory time was lost due to German air raids during the Battle of Britain.

The Mosquito proved its speed in January 1941, when it reached a top speed of 392 mph (631 km/h), flying 32 mph (51 km/h) faster than the Spitfire Mk.II it was racing against. Later versions could reach a top speed of up to 415 mph (668 km/h), making it one of the fastest propeller-driven planes of the war. Mass production was authorized in June 1941 with an order of 19 photoreconnaissance, 176 fighter and 50 unarmed fast bomber variants. An April 1941 demonstration was attended by U.S. General Henry "Hap" Arnold, who became chief of the Army Air Forces later that year, and his aide Major Elwood "Pete" Quesada, who would take Eisenhower on a recon mission later in the war. (Read our article) They were both impressed by the plane, but the U.S. eventually decided not to adopt it (except for temporarily using a small number of recon and night fighter planes); there weren't enough carpenters to build the wooden planes in bulk, and the P-38 Lightning (Like Lightning from a Clear Sky) was doing a good job in a similar role.

The finished Mosquito used a variety of timber for its fuselage and wings, including Ecuadorian balsa, birch, spruce and plywood, earning the nickname “Wooden Wonder.” (Lord Beaverbrook’s own nickname for it was “Freeman’s Folly” in reference to Wilfrid Freeman’s staunch support of the project.) The plane was fast and maneuverable, but combat use revealed some weaknesses in the construction. Several crashes in the Far East were first attributed to the glue, which couldn't withstand tropical heat and monsoon conditions. A follow-up investigation revealed that the problem was not with glue, but with the planes being stored in the open during the monsoon: the excessive humidity made the wood first swell than shrink during drying, causing structural damage. A later inquiry square put the blame on faulty construction, after all, but the Air Ministry was happy to stick with the humidity theory, and some changes were implemented to protect the planes against the tropical rain.

On its introduction, the Mosquito was about as fast as its most dangerous opposition, the Bf 109F (The Bf 109) and the Fw190A (Focke-Wulf Fw 190). Despite the small speed difference, the Mosquito still had a major advantage unless these interceptors had already scrambled due to an early visual sighting. Late in the war, the jet-powered Me 262 (Ushering in the Jet Age) could catch the Mosquito, but was not available in sufficient numbers, and one particular version of the photo-recon Mosquito could actually climb to an altitude beyond even the Me 262's service ceiling.

A true multi-role warplane, the Mosquito came in numerous different versions, each with different "marks" due to constant improvements: photo-reconnaissance (PR), bomber (B), fighter (F), night fighter (NF), fighter-bomber (FB), torpedo bomber (TR) with fold-up wings to fit more on a carrier, and trainer (T), many built in Canada or Australia, each with varying modifications and weapon loadouts. Typical gun armament was four .303 caliber Browning machine guns (The .30 cal Browning) and four 20 mm Hispano autocannons. Bomb load could be up to 4,000 lb (1,800 kg), allowing the Mosquito to carry a single "Cookie" blockbuster bomb, or a number of smaller ones.

The FB Mk. XVIII fighter-bomber, nicknamed the Tsetse after the deadly African fly, carried a single 57 mm 6-pounder anti-tank gun equipped with an auto-loader and 25 rounds, and either two or four Brownings whose job was to help sight the gun on the target. The 18 representatives of this version served well against German U-boats and convoys, despite the fact that turning or banking during at attack dive could jam the gun.

Other modified Mosquitos carried that Highball, a smaller version of the famous Upkeep bomb used in Operation Chastise, the "Dambusters" raid (The Dambusters Raid).  Their mission was to sink the German battleship Tirpitz, the sister ship of the Bismarck (Hunting the Bismarck – part I), but the target was sunk by Lancaster bombers before the mission could be carried out.

Night fighter versions not only hunted German planes landing at airfields, but also protected British night bomber raids. In 1943, the Germans developed an effective tactic against bombers swarms with their own night fighters merging into the bomber streams under the cover of darkness. Mosquitos were equipped with special devices that could detect the emissions of the Germans' own airborne radar and their friend-or-foe signals, allowing them to hunt down these intruders. Meanwhile, the Germans became acquainted with Moskitoschreck, "Mosquito terror," the constant fear of an unexpected Mosquito attack during a nighttime landing. Many German planes and pilots were lost because they were so afraid of a Mosquito attack that they rushed their night landing attempt and crashed.

Other Mosquito varieties were used as diversion bombers and pathfinders for night raids. Diversion bombers attacked secondary targets to distract German interception efforts, and dropped Window, an early form of chaff, to create false radar images of incoming bomber groups. (Deception on D-Day) Meanwhile, pathfinders flew ahead of the real heavy bomber swarms and dropped flares to illuminate targets.

The Mosquito also had a track record of special operations. In September 1942, four Mosquitos attacked the Gestapo headquarters in Oslo, the capital of Nazi-occupied Norway, as a morale booster operation. The mission ended in failure. At least four bombs hit the target building, but one failed to detonate, and the other three punched their way through the back wall, detonating among residential buildings and killing or injuring 80 civilians, all at the loss of one bomber. Nevertheless, the British government used the mission to unveil the Mosquito, whose existence was previously kept a secret from the public.

On January 30, 1943, another special mission was planned, this time directly to Berlin. It was the 10th anniversary of the Nazi seizure of power (Becoming Führer), and a morning attack on the main Berlin broadcasting station managed to knock Luftwaffe chief Hermann Göring off the air for an hour; a second run in the afternoon disrupted another speech, this one by Propaganda Minister Joseph Goebbels. This second speech was not taken off the air, but Goebbels had to deliver it with the background noise of bomb blasts and flak fire. Göring, who previously boasted that no Allied bombs would ever hit Berlin, was livid and ranted at a group of German aircraft manufacturers: "In 1940 I could at least fly as far as Glasgow in most of my aircraft, but not now! It makes me furious when I see the Mosquito. I turn green and yellow with envy. The British, who can afford aluminium better than we can, knock together a beautiful wooden aircraft that every piano factory over there is building, and they give it a speed which they have now increased yet again. What do you make of that? There is nothing the British do not have. They have the geniuses and we have the nincompoops. After the war is over I'm going to buy a British radio set – then at least I'll own something that has always worked."

In February 1944, Mosquitos and Typhoons executed Operation Jericho, named after the Old Testament miracle of the walls of Jericho falling down. The flight attacked the prison at the French city of Amiens at low altitude to blow holes in the wall, kill the German guards and blow open the cell doors. 255 of the 832 prisoners managed to escape, though 182 were recaptured later and many others were murdered in reprisal killings. The mission is still surrounded by mystery today. It was long believed that the French Resistance asked for it to save their comrades who were about to be executed, but later research shows that the resistance did not actually know about the operation at the time.

In October 1944, Mosquitos attacked another Gestapo headquarters, this time in Aarhus, Denmark. This raid was more successful and killed 59 German police officers, office workers and Gestapo agents, albeit at the collateral cost of the lives of 10 Danish civilians and a Danish prisoner who was in the building and under interrogation.

A similar but more tragic attack was mounted against yet another Gestapo headquarters, this time in the Danish capital of Copenhagen, in March 1945. This mission was actually requested by the Danish resistance. The building was successfully destroyed, along with 55 German soldiers and 47 Danish Gestapo-employees. Seven of the attacking 50 bombers and fighters were lost. The civilian cost, however, was far higher. One of the Mosquitos in the first wave hit a lamppost and crashed into a Catholic school. The third wave, possibly confused by the smoke and the wreckage, bombed the same area, killing 86 children, 10 nuns, 8 teachers and 21 other civilians.

Several Mosquitos also flew in an even more special operation which required them to be completely unarmed. The British Overseas Airways Corporation (BOAC) set up a route between Scotland and neutral Sweden, which was selling industrial goods to both sides in World War II. Mosquitos were fast enough to get there and back without fear of German interception, but they had to be converted into civilian planes flown by civilian pilots to comply with neutrality laws. The purpose of these trips was ostensibly to buy strategically valuable goods such as precision ball bearings and machine-tool steel, but diplomatic bags and human passengers also found their way onboard.

Some 6,000 passengers were ferried by BOAC flights (including other plane types) between Stockholm and Britain, some of them spies or British representatives on a secret visit, many others escaping Norwegians. The most famous passenger inside a Mosquito bomb bay was Danish nuclear and quantum physicist Niels Bohr, who later joined the British atomic weapon project. As it happens, Bohr did not put on his oxygen mask and lost consciousness for most of the flight.

All in all, 7,781 Mosquitoes were built for the war; 30 of them still exist today, five of them airworthy. One can be seen at the Imperial War Museum Duxford on our Britain at War Tour.

Save 25% until December 2!