The Henschel Hs 126 was the Luftwaffe's main short range reconnaissance aircraft in the early years of the Second World War, taking part in the invasion of Poland, the campaign in the west in 1940 and the first year of the invasion of the Soviet Union.
The Hs 126 was an all-metal stressed-skin parasol wing monoplane, with a fixed undercarriage. The wing was supported by four main struts, two to each side, with extra bracing between the fuselage and the centre of the wing. The main wheels were mounted on single struts, with internal bracing (cantilevered), attached at ninety degrees to the fuselage. The level angular wing was slightly swept back, with straight edges, and a V-shaped notch at the centre of the trailing edge, above the pilot's cockpit. The cockpit was semi-enclosed, with the pilot under glass but the observer in an open position.
The Hs 122 appeared in 1935. It was similar in appearance to the Hs 126, but its performance was disappointing. Henschel were asked to redesign the aircraft to use the new BMW Bramo Fafnir 323 radial engine. A team led by Henschel's chief designer, Dipl Ing Freidrich Nicolaus, took the opportunity to redesign most elements of the aircraft, to produce the Hs 126.
The new aircraft was two feet longer than the Hs 122. The basic parasol wing layout was retained, but a new more angular wing was developed. A cantilever undercarriage was used, allowing each wheel to be supported by a single streamline strut in place of the two struts of the Hs 122. The front half of the cockpit, containing the pilot, was enclosed, while the observer/ gunner's section remained open. It was to be powered by the Bramo 323 Fafnir radial engine.
The first prototype, Hs 126V1, was produced by rebuild an Hs 122. It was powered by a Junkers Jumo 210 liquid-cooled inline engine, installed because of delays to the BMW engines. The second and third prototypes received 830hp Bramo-Fafnir 323A-1 nine-cylinder radial engines, as did the pre-production A-0 aircraft, although not the first production aircraft. It made its maiden flight late in 1936.
The second prototype, Hs 126V2, was given a supercharger and modified tail, while the V3 returned to the original tail, and had a modified undercarriage, in which the struts were at ninety degrees to the fuselage, instead of sloping backwards.
Ten pre-production A-0 aircraft were produced, powered by the BMW Fafnir engine. They were generally similar to the V3 prototype. The A-0s were used for service evaluation in the spring of 1938, and were well received by the Luftwaffes' reconnaissance groups.
The A-1 was the first production version of the Hs 126. A shortage of the Fafnir engines meant that it was powered by the BMW 132DC, which provided 890hp at take-off. The A-1 was armed with two 7.92mm machine guns - a fixed forwarding firing MG 17 and a flexibly mounted MG 15 in the rear cockpit. It had an internal bay that could carry a single Zeiss camera or ten 22lb/10kg bombs. A second hand-held camera was attacked to the port side of the cockpit. Additionally a single SC 50 bomb (110lb/ 50kg) could be carried a rack behind the port undercarriage leg.
The A-1 first appeared early in 1938, and entered service with Aufklärungsgruppe 35 in the autumn of 1938. The type made its combat debut in Spain, where it served with A/88.
By the middle of 1939 the BMW Fafnir engine was finally available in significant numbers, and production switched to the Hs 126B-1. This was powered by either the 850hp BMW 323A-1 or the 900hp A-2 or Q-2. Although these engines produced a similar level of maximum power to the BMW 132 series, they were more effective at altitude, and reduced the take-off run. The B-1 was also given a more effective radio, the FuG 17 VHF.
Around 600 Hs 126s of all types were produced, 100 before the war and 505 between 1 September 1939 and the end of production in January 1941.
The Hs 126 made its combat debut in Spain. In the autumn of 1938 six A-1s were delivered to Aufklärungsstaffel 88 (A/88) of the Condor Legion, replacing the Heinkel He 45. The new aircraft performed well in the reconnaissance and light bomber role. One was lost, and the remaining five were transferred to the Spanish Air Force at the end of the war. The Hs 126 was also operated by the Greeks, who purchased sixteen aircraft and used them to equip the 3rd Army Co-operation Squadron.
The Hs 126 entered Luftwaffe service with Aufklärungsgruppe 35 in the autumn of 1938, and by September 1939 had replaced the Heinkel He 45 and He 46 with most of the reconnaissance groups.
The Hs 126 was used by the short-range reconnaissance units of the Luftwaffe. These units were officially known as Aufklärungstaffeln (Heer) at squadron level, and Aufklärungsgruppe at group level. The normal next left of organisation, the Geschwader, wasn't used. As a result the system of abbreviations used for reconnaissance units differed from the standard. In the more familiar fighter or bomber squadrons the Geschwader was the final element of the abbreviation, with staffeln indicated by arabic numerals and groups by roman numerals (thus 1./JG 132 was the 1st staffel of Jagdgeschwader 132, while I./JG 132 was the first group. In the reconnaissance groups the first digit was always the staffel, the second the group, so 1.(H)/23 (or 1.(H)/Aufkl.Gr 23) was the first short range (army) staffel of aufklärungsgruppe 23. The number of staffeln in each group varied depending on need. At the start of the war each staffel was allocated to a particular army corps, and came under the direct command of the army.
At the outbreak of the Second World War the Hs 126 equipped the Heer squadrons of Aufkl.Gr 10, 11, 12, 13, 14, 21, 23, 31, 32 and 41, group 35 having been disbanded. Thirteen squadrons used the aircraft during the Polish campaign, where it was able to operate as a bomber and ground attack aircraft, as well as in its normal army co-operation, reconnaissance and artillery spotter roles.
Once the fighting was over in Poland the reconnaissance groups began to move west. The Hs 126 began to be seen over the Maginot Line, and it was present in large numbers during the Allies campaign in the west in May 1940. For the first time the Hs 126 came up against large numbers of modern fighters, and was found to be vulnerable - twenty were lost between 10-21 May. It was decided to put the Focke-Wulf Fw 189 into production, but that aircraft wouldn't appear in large numbers until 1942.
In the aftermath of the campaign in France one squadron, 2.(H)/14 took the Hs 126 to North Africa, where it remained in service until August 1942.
This left forty-seven squadrons equipped with the Hs 126 for the invasion of the Soviet Union. The aircraft was still vulnerable, and began to suffer heavy losses. In the spring of 1942 the Fw 189 began to replace it, and by the end of the year it had gone from the front line.
Most of the surviving Hs 126s were used as training aircraft. Some were used to equip II. and III./Luftlangdeschwader 1 (LLG 1), where they were used to tow the DFS 230 glider.
In the autumn of 1942 the Hs 126 made a return to the front line (as did a number of earlier biplane types), with the night harassment groups (Nachtschlachtgruppen). The Hs 126 was used by NSGr 7 in the Balkans, 3./NSGr 11 in Estonia and 2./NSGr 12 in Latvia. It remained in use in the Balkans until April 1945 and the German collapse.
Engine: BMW Bramo Fafnir 323 air cooled 9 cylinder radial engine
Crew: two - pilot and observer/ gunner
Wing span: 47ft 6 ¾ in
Length: 35ft 7in
Height: 12ft 3 1/2in
Fully loaded weight: 6,813lb
Max Speed: 217mph at 13,120ft
Climb to 13,120ft: 7.2 minutes
Service Ceiling: 27,000ft
Range: 445miles at 208mph
Endurance: 2 hours 15 minutes
Armament: Two 7.92mm MG 17 machine guns: one fixed forward firing, one flexibly mounted in rear cockpit
Bomb-load: Ten 22lb/10kg bombs in fuselage bay or one 110lb bomb under port wing strut