1935 dive bomber series by Henschel
The Henschel Hs 123 was a single-seat biplane dive bomber and close-support aircraft flown by the German aircraft manufacturer Henschel. It was the last biplane to be operated by the "Luftwaffe".
The Hs 123 started development in 1933 in response to a request for a single-seat biplane dive bomber. Henschel's design team opted to produce an aircraft with all-metal construction, relatively clean lines and a high level of manoeuvrability. Its principal competitor was the Fieseler Fi 98, which was eventually cancelled when the Hs 123 proved to be more promising. On 1 April 1935, the first prototype performed its maiden flight; a total of four prototypes were produced, the fourth of which featured strengthened centre-section struts after two of the earlier prototypes were lost due to structural failures during high speed dives. 
Upon its introduction to "Luftwaffe" in autumn 1936, the Hs 123 quickly displaced the Heinkel He 50 biplane, but was only viewed as being a "stop-gap" measure until the arrival of the Junkers Ju 87 "Stuka" later that same decade. In 1938, the type was dispatched to Spain to fight with the "Legion Condor" in the Spanish Civil War; the type reportedly performed well in this theatre, particularly in terms of the phycological impact of its attacked upon the enemy. The Spanish Nationalists was impressed with the type and opted to procure additional aircraft for their own use. The temporarily-organized 15th Squadron of the China Central Air Force Academy Group also flew combat missions with its Hs 123s around this time, attacking Imperial Japanese warships along the Yangtze River.
The "Luftwaffe" opted to dispatch the type during the early and middle portions of the Second World War, first deploying it during the Polish Campaign. In 1940, the type saw action in the "blitzkrieg" attacks through the Netherlands, Belgium and France and the early portion of the Balkans Campaign. Numerous Hs 123s saw combat during the start of Invasion of the Soviet Union in 1941. The Hs 123 proved to be relatively robust, durable and effective in combat, especially in severe conditions (such as those present in the Eastern Front); it was commonly modified in the field to carry additional machine guns, more armour, and various other changes. It continued to see front-line service until 1944, only to be withdrawn due to a lack of serviceable airframes and spare parts (production ended in the Autumn of 1938).
Design and development.
Henschel was a German locomotive manufacturer. Soon after Hitler's rise to power, Henschel decided to start designing aircraft, one of the first being the Hs 123. This aircraft was designed to satisfy the a requirement issued in 1933 by the "Reichsluftfahrtministerium" (RLM). This requirement sought a new dive bomber to equip the newly-established "Luftwaffe"; it was specified that this aircraft should have a biplane configuration and provide only a single seat for the pilot. Henschel and rival firm Fieseler, who responded with the Fi 98, competed for the same requirement.
In comparison to the Fi 98, the Hs 123 was noticeably more streamlined and possessed relatively clean lines. In terms of its general configuration, it was a sesquiplane, whereby the lower wings were significantly smaller than the top wings. The aircraft featured all-metal construction, both the fuselage and fixed tail surfaces had a light alloy covering while the majority of the wings were also metal skinned; in contrast, every control surface and the rear portion of both wings had a fabric covering. The design eliminated the use of bracing wires, instead relying on single faired interplane struts. The Hs 123 was also outfitted with cantilever main landing gear legs that were attached directly to the smaller stub-like lower wings.
On 1 April 1935, the first prototype, the Hs 123 V1, performed its maiden flight. During its first public demonstration flight, which was conducted on 8 May 1935, it was piloted by "Generalluftzeugmeister" Ernst Udet, a First World War ace. The first three Henschel prototypes, the first and third of which were powered by 485 kW (650 hp) BMW 132A-3 engines while the second by a 574 kW (770 hp) Wright Cyclone, were tested at Rechlin in August 1935. Only the first prototype had "smooth" cowlings; from that point on, all aircraft had a tightly fitted cowling that included 18 fairings covering the engine valves. The third prototype was the first to carry armaments.
The performance of the Hs 123 V1 prototype was such that it quickly eliminated any prospect for the more conventional Fi 98 being awarded the contract; further work was promptly cancelled after a sole prototype had been constructed. During flight testing, the Hs 123 proved to be capable of pulling out of "near-vertical" dives, however, two of the first three prototypes subsequently crashed due to structural failures in the wings that occurred when the aircraft was being flown in a high-speed dive. Accordingly, the fourth prototype incorporated improvements to rectify these problems, the principal change being the adoption of sturdier centre-section struts.
Following the completion of all remaining tests, the Hs 123 was ordered into production with a 656 kW (880 hp) BMW 132Dc engine. During the summer of 1936, the first production standard aircraft came off the assembly lines, which had been established at Henschel's Schönefeld and Johannisthal facilities. The Hs 123 was intended to replace the Heinkel He 50 biplane reconnaissance and dive bomber as well as to function as a "stop-gap" measure until the Junkers Ju 87 "Stuka" became available. As such, production was limited and no upgrades was seriously considered.
However, Henschel opted to work on an improved version, the "Hs 123B", during 1938. A proposal to fit the aircraft with a more powerful 716 kW (960 hp) "K"-variant of its BMW 132 engine did not proceed beyond the prototype stage, the Hs 123 V5. The "V6" prototype fitted with a similar powerplant and featuring a sliding cockpit hood was intended to serve as the "Hs 123C" prototype. In total, 265 aircraft are believed to have been produced. Production of the Hs 123A was terminated in Autumn 1938. A prototype Hs 123B and a prototype Hs 123C were produced just prior to production of the Hs 123A ended.
The majority of Hs 123s were delivered to the "Luftwaffe". However, several Hs 123s were exported to China while 14 were transferred to Spain's Nationalist Air Arm; both operators would use their aircraft in combat.
Operational history.
Initial operations.
During 1936, a small pre-production batch of "Hs 123A-0"s was completed and used for service evaluation by the Luftwaffe. This initial group was followed by the slightly modified "Hs 123A-1" series, the first production examples. The service aircraft flew with an armoured headrest and fairing in place (a canopy was tested in the Hs 123V6) as well as removable main wheel spats and a faired tailwheel. The main weapon load of four SC50 50 kg (110 lb) bombs could be carried in lower wing racks along with an additional SC250 250 kg (550 lb) bomb mounted on a "crutch" beneath the fuselage. The usual configuration was to install an auxiliary fuel "drop" tank at this station that was jettisoned in emergencies. Two 7.92 mm (.312 in) MG 17 machine guns were mounted in the nose synchronized to fire through the propeller arc.
The aircraft entered service at StG 162 in autumn 1936. Its career as a dive bomber was cut short when the unit received its first Ju 87A during the following year. The remaining Hs 123s were incorporated into the temporary "Fliegergeschwader" 100 at the time of the Munich Crisis. The "Geschwader" (wing) had been created as an emergency measure, equipped with obsolete aircraft and tasked with the ground attack role. With the signing of the Munich Agreement on 30 September 1938, the crisis was over and the "Geschwader" was disbanded, the "gruppen" being transferred to other established units. By 1939, despite its success in Spain, the "Luftwaffe" considered the Hs 123 to be obsolete and the "schlachtgeschwader" (close-support wings) had been disbanded with only one "gruppe", "II.(Schl)/LG2" still equipped with the Hs 123.
Spanish Civil War.
During the same time, at the request of "Oberst" (later "Generalfeldmarschall") Wolfram von Richthofen, chief of staff of the "Legion Condor", five aircraft had been deployed to Spain in early 1937 as a part of the "Legion Condor", intended to be used as tactical bombers.
In their intended role, the Hs 123s proved to be somewhat of a failure, hampered by their small bomb capacity and short range. Instead, the Hs 123s based in Seville were used for ground support, a role in which their range was not such a detriment, and where the ability to accurately place munitions was more important than carrying a large load. The combat evaluation of the Hs 123 demonstrated a remarkable resiliency in close-support missions, proving able to absorb a great deal of punishment including direct hits on the airframe and engine. The Nationalists in Spain were impressed with the Hs 123's performance in battle, purchasing the entire evaluation flight and ordering an additional 11 aircraft from Germany. The Spanish Hs 123s were known as "Angelito" (dear angel or little angel), and at least one Hs 123 was in service with the "Ejército del Aire" (Spanish Air Force) after 1945.
Second Sino-Japanese War.
Twelve Hs 123s that were originally ordered by Portugal were exported to China. They were extensively used as dive bombers by the temporarily-organized 15th Squadron of the China Central Air Force Academy Group, operating against Imperial Japanese warships along the Yangtze River, especially during 1938.
Second World War.
Service from Poland to Greece.
At the outbreak of hostilities, the surviving 39 Hs 123s assigned to II. (Schl)/LG 2, were committed to action during the Polish Campaign. This single unit proved to be particularly effective. Screaming over the heads of enemy troops, the Hs 123s delivered their bombs with devastating accuracy. A frightening aspect of an Hs 123 attack was the staccato noise of its engine that a pilot could manipulate by changing rpm to create "gunfire-like" bursts. The Hs 123 proved to be quite rugged and capable of absorbing a high amount of damage while continuing to fly. Operating from primitive bases close to the front lines, the type was considered by ground crews to be easy to maintain and reliable in field conditions.
The Polish campaign was a success for the Hs 123 in spite of it being considered obsolete by several figures within "Luftwaffe" high command. Within a year, the Hs 123 was again in action in the "blitzkrieg" attacks through the Netherlands, Belgium and France. During one noteworthy engagement on 22 May 1940, the two "gruppen" equipped with the type held off an attacking force of around 40 tanks against their own forward base in Cambrai.
General Heinz Guderian was continually impressed by the quick turnaround time offered by II.(Schl)/LG 2. Often positioned as the "Luftwaffe"'s most-forward based combat unit, the Hs 123 flew more missions per day than other units, and again proved their worth in the close-support role. With Ju 87s still being used as tactical bombers rather than true ground support aircraft and with no other aircraft capable of this mission in the "Luftwaffe" arsenal the Hs 123 was destined to continue in service for some time, although numbers were constantly being reduced by attrition. While the Hs 123 proved to be particularly effective against ground attacks, they were vulnerable to enemy fighter interception.
The Hs 123 was not employed in the subsequent Battle of Britain as the English Channel proved an insuperable obstacle for the short-ranged aircraft. The sole operator, II.(Schl)/LG 2 went back to Germany to re-equip with the Messerschmitt Bf 109E fighter bomber ("Jabo") variant. The Bf 109E fighter bomber was not capable of carrying any more bombs than the Hs 123, however, it did have a greater range and was far more capable of defending itself. It did have some downsides, including the notoriously tricky taxiing, ground handling, and takeoff/landing characteristics of the Bf 109, which were exacerbated with a bomb load.
At the beginning of the Balkans Campaign, the 32 examples of the Hs 123 that had been retired after the fall of France were taken back into service to equip "10.(Schl)/LG 2". The aircraft performed well enough to warrant its continued use by the "Luftwaffe".
Eastern Front service.
At the start of Operation Barbarossa, the single "Gruppe" of the "Luftwaffe" that was dedicated to ground support was II.(Schl)/LG 2, operating 22 Hs 123s (along with 38 Bf 109Es). In service use