The Junkers Ju 87 ‘Stuka’ is one of the most recognisable planes from World War 2, the gull wings and fixed landing gear make the plane a dead giveaway. But if not more recognisable is the scream that bellowed out from the plane as it plummeted towards the Earth.
Germany’s want for a dive bomber arose after the Luftwaffe’s reasearch and development director, and World War One fighter ace, Ernst Udet flew a Curtiss F11C Goshawk in the early 30’s. Design began on the Ju 87 in 1933, originally using a 700 horsepower, 22 litre, Rolls-Royce Kestrel V-12. The Ministry of Aviation did not want to rely on a British engine however, so a Jumo 210 D inverted V-12 was fitted.
The Stuka was packed with revolutionary designs. Being the only dive-bomber that could attack from 90 degrees, the Stuka was fitted with ‘dive-brakes’ that would raise the nose to bring the plane out of a dive in case the pilot suffered a g-force induced black-out. One year after its first take-off, the Stuka was sent to the front lines of the Spanish Civil War in 1936, and from here, the plane would proceed to the battlefields of Europe.
On the planes entrance to the European theatre, the Stuka was modified with the addition of two 70cm propellers at the top of the landing gear. As the plane engaged in a dive, the air flow would drive the two propellers, driving sirens and creating that very familiar noise in an attempt to damage the psyche of the enemies on the ground. The Germans called it ‘Schreklichkeit’ or ‘Frightfulness/Awfulness’, a principle that employed psychological warfare as a tool of war.
The sirens were named Jericho Trumpets, a biblical reference from the book of Joshua. After being freed from Egypt, the ex-slaves were instructed by God to take their promised land by conquest. Once a day, the Israelites marched round the city of Jericho blowing their trumpets and on the seventh day, the walls guarding it fell. Doing God’s work, the Israelites stormed the city killing every man, woman and child. Perhaps this gives us an insight into how the Germans assessed the war.
During the early days of World War 2, the sirens proved extremely effective. The noise of an incoming air attack would leave the fear stricken enemy soldiers scrambling for cover and not shooting at the incoming tanks and ground forces.
The sirens did come with disadvantages however, the drag they created cost the plane 15mph, making the dive bomber an easier target for the more advanced allied fighter planes. The Stuka became such easy prey for the enemy fighters in fact, the dive-bomber needed a fighter escort to its targets in the Atlantic convoys during the Battle of Britain.
As the plane became dated, so did the trumpets, now only alerting defenders of the planes arrival. Pilots can be seen ditching the sirens from as early as 1940, prompting a similar ‘Whistle’ technology to be fitted to the bombs instead.
Due to lack of replacement, the Stuka remained in service until the end of the war but its production ceased in August 1944. The sirens themselves have become synonymous with aerial combat in World War 2, partly in thanks to Hollywood using the noise to denote any aircraft in their films.