The Fieseler Fi 156 Storch (Stork) is widely considered to have been the best army cooperation aircraft to see large-scale service during the Second World War, serving with the German Army on just about every front, and possessing a very impressive short take-off and landing capability.
The Storch was developed by a team led by Gerhard Fieseler, a First World War fighter ace and inter-war aerial acrobat, his chief designer Reinhold Mewes and his technical director Erich Bachem. It was originally designed as a private venture, to be produced in possible military and civil versions.
Five prototype Fi 156s were built. The second, V-2 (D-IGLI) was completed first, and sent to Rechlin for tests during 1936. After these successful tests Fieseler were ordered to built more prototypes, but at the same time a specification based on the Fi 156 was issued to the German aircraft industry.
Three companies produced aircraft in response to the new specification, but none were real competitors to the Storch. The Messerschmitt Bf 163 was similar to the Storch, but arrived too late to be considered (not making its maiden flight until early in 1938). The Focke-Wulf Fw 186 autogyro was too radical a design and was not considered to be robust enough for the battlefield. The Siebel Si 201 was an unusual aircraft with a pusher engine that was acceptable in the air, but failed to match the Storch's STOL capabilities.
The first two Fi 156 prototypes were followed by the V-3 and V-5, both with military equipment, and by the ski-equipped V-4 of mid 1937. By this date the 10 pre-production A-0 aircraft were also being completed, and the new aircraft was first seen in public at the Fourth International Flying Meet at Zurich on 1 August 1937, where its short take-off and landing capabilities (STOL) impressed the audience.
The V-2 demonstrated the impressive performance of the entire series. During tests with a loaded weight of 2,740lb it could fly under control at 32mph, while with an 8 mph headwind it could take off in 150ft and land in 54ft - only just more than its own width. A Storch would later be recorded as landing in 15ft with a stronger head wind and a ploughed field to help!
Sources disagree on the total number of Fi 156s accepted by the Luftwaffe, with figures ranging from just under 2,000 up to 2,871. Production began slowly, but 227 were accepted in 1939, 216 in 1940 and 430 in 1941.
By 1942 Fieseler's Kassel Works were heavily committed to the production of the Bf 109 and Fw 190. During 1942 the Kassel Works still completed 484 Fi 156s, but that year also saw the first aircraft come off a new production line at Puteaux in France, originally used to build the Morane Saulnier M.S.406. Morane Saulnier built 121 aircraft in 1942, and continued production of the type after the war with a variety of different engines (most successfully as the M.S.502 Criquet).
The last Fieseler built aircraft was completed in October 1943. Production then shifted to the firm of Leichtbau Budweis in Czechoslovakia, which built one aircraft in 1943 and 72 in 1944. Production then moved again, this time to Mraz in Chozen, where 64 aircraft were built during the war. Mraz also continued construction of the Storch after the end of the war, with the designation K-65 Cap.
The Fi 156 Storch was a surprisingly conventional aircraft. It was a three-seat high-winged monoplane, with two passengers sitting in tandem behind the pilot. The fuselage had a welded steel tube framework and a tight fabric covering. The strongly built cabin had a glazed area wider than the fuselage, giving an excellent view straight down.
The wings had a wooden frame with a fabric cover and were braced to the bottom of the fuselage by steel-tubes. They could be folded backwards. They had fixed aluminium slots along the entire leading edge. The trailing edge had wooden slotted flaps, with the outer sections used as ailerons. Both of these features were designed to increase the lift provided by the wings at low speeds, and helped give the aircraft its impressive low speed and STOL abilities. The fin was made of metal and fabric, while the rest of the tail had a wooden frame and plywood skin.
The Fi 156 was powered by the air cooled Argus As 10 inverted inline engine, a very reliable engine that was able to cope with the extreme cold found on the Eastern Front, and with the difficult conditions in North Africa.
The undercarriage played an important part in the success of the aircraft. The two main wheels were mounted on strong, very long, energy absorbing oleos which were attached to the wing roots, and were braced to the lower fuselage. This meant that the undercarriage was able to cope with the shock of the very steep landings performed by the aircraft. The only flaw with the undercarriage was that the small wheels were often damaged by ruts or large stones.
The standard fuel load on the Storch was 150 litres, carried in two 75 litre/ 16.28 imperial gallon fuel tanks, one in each wing. A 45 gallon/ 205 litre tank could be installed in place of the two passenger seats for longer journeys.
The Storch is often said to have had no Allied equivalent, but this is not the case. Its most direct British equivalent was the Westland Lysander, another high-wing monoplane, and designed to carry out many of the same roles. The Lysander could carry a small bomb load and came with fixed forward firing guns, but it was much heavier than the Storch, used an engine that was nearly four times as powerful as the Argus engines used by Fieseler, and needed more space to take-off or land.
The Allied aircraft with the best claim to be the equal of the Storch was probably the American Piper L-4 Grasshopper. This was yet another high-wing monoplane, and performed most of the same roles as the Storch, but was much lighter and smaller than the German aircraft, and was powered by a 65hp engine. It had a stall speed of 39mph, so couldn't fly quite as slow as the Storch, and nor could it quite match its STOL capabilities, but it came close. At least twice as many L-4s were produced as Storchs, with production reaching over 5,500 aircraft.
The Fi 156A-1 began to enter Luftwaffe service in 1937, and almost immediately a number were sent to Spain to serve with the Condor Legion. As production began to speed up one or two Fi 156C-1s were issued to every Gruppe in the Luftwaffe, and to most units in the Army and frontline elements of the SS. The Storch was also used as transport aircraft by senior members of the General Staff and by commanders in the field, most famously Kesselring and Rommel (and eventually by Montgomery on the Allied side!).
The Storch saw service on every front where the German Army fought, from the Arctic and Norway, through the Russian Front and down into the Western Desert, as well as in Western Europe, both in 1940 and in 1944-45. It was a very survivable aircraft - when flying at 34mph it was very difficult for modern fighter aircraft to actually catch it, and each Storch was said to have had a combat life ten times longer than the average Bf 109!
The Storch was used for a very wide range of functions, amongst them artillery spotting, reconnaissance, staff liaison, as an air ambulance, to rescue downed airmen from behind enemy lines (especially valuable in North Africa, where it was operated by two rescue squadrons or Wüstennotstaffeln, and in Russia), as a cable laying aircraft, and on a number of special missions.
The Storch was used for two of the most famous single flights of the Second World War. The first came on 12 September 1943 when a company of paratroopers rescued Mussolini from the Campo Imperatore Hotel on the pinnacle of Gran Sasso in the Abruzzi Mountains. The Storch made a daring landing on top of the mountain, before managing to take off despite being rather overloaded with passengers, amongst them Otto Skorzeny, whose role in the raid is somewhat controversial, and whose insistence on being flown off in the Storch nearly caused the failure of the entire mission.
The second came in the last days of the war, during the battle for Berlin. Goering attempted to seize power on the grounds that Hitler was now trapped in the city, but he had misjudged the situation and was removed from all of his posts. At Hitler's order the famous test pilot Hanna Reitsch flew Generaloberst Ritter von Greim into the besieged city, where he was given command of what was left of the Luftwaffe, before flying him back out again - an impressive but entirely pointless flight.
Captured Fi 156s were used in surprisingly large numbers by the RAF. At least 47 were used by front-line squadrons in the Mediterranean theatre, and more than sixty were taken onto RAF charge. Amongst them was VM472, which became the personal aircraft of Field Marshal Montgomery.
A small number of Fi 156As were built in the A-0 pre-production and A-1 production series. They were similar to the V-3 prototype.
The Fi 156B was to have used moveable slots on the front of the wings, and would have been faster than the standard Fi 156. One B-0 was probably built, but the type never entered production.
The Fi 156C was the main production version of the aircraft. It had a modified rear canopy capable of carrying a 7.92mm machine gun, which was installed on all but the C-1 version.
The Fi 156D was a dedicated ambulance aircraft with improved access for stretchers.
The Fi 156E used a modified undercarriage with tandem wheels and a short track. Only ten were built.
Fi 156F or P
The Fi 156F or P was a Police or anti-Partisan version of the aircraft, armed with small bombs and forward firing machine guns.
The Fi 156U was the designation given to an experimental version of the aircraft used to test out bomb racks.
After the war the Storch was produced in Czechoslovakia as the Mraz K.65 Cap, and by Morane Saulnier in France as the M.S. 500, M.S. 501 and M.S. 502, with the designation indicating the type of engine in use.
Engine: Argus As 10C-3 eight cylinder air-cooled
Wing span: 46ft 9in
Length: 32ft 6in
Empty Weight: 2,050lb
Loaded Weight: 2,920lb
Max Speed: 109mph at sea level
Cruising Speed: 81mph or 93mph at 3,280ft
Climb rate: 905ft/ minute
Service Ceiling: 15,090ft
Range: 248 miles at 93 mph at 3,280ft
Armament: One flexibly mounted 7.9mm MG 15 in rear of cabin