The Henschel Hs 129 also played a part in the Battle for the Kursk Salient. Built in fewer numbers than the Junkers Ju 87G this twin-engine close support aircraft’s role was not insignificant. Its rocky career began with totally inadequate engines. The Argus A-1 twelve cylinder inverted-vee, air-cooled engine developed only 465 horsepower for take-off. The fuselage was built around the armored cockpit made up of armor plate six to twelve millimeters thick and weighing in at nearly 500 kilograms. In the nose was a pair of 20 mm cannon and a pair of 7.9 mm machine guns. Underwing racks carried either two 50 kg bombs or twenty-four 2 kg anti-personnel bombs.
The prototype made its first flight in early 1939 and the machine was criticized for being seriously under powered and for providing limited visibility for the pilot. The priority for this machine remained low initially, so the redesign received more support only when the need for more close support aircraft became more apparent during the campaigns in Poland and France. The conquest of France made available the Gnome-Rhone 14 M radial engine. This engine developed 700 horsepower for take-off. Even these engines allowed only a 400 kilometer per hour maximum speed. A limited time was allowed for redesign, so, when the aircraft entered service in North Africa in March 1942 and the eastern front in May 1942, front line units learned that the engines were vulnerable to dust and could absorb only minimal combat damage. Additionally, the armament was totally inadequate for anti-armor work.
Field modifications provided for Hs 129Bs included an increase in armament to include a 30 mm cannon with 30 rounds in a detachable ventral pack. This weapon was proved to be unable to penetrate the 45 mm armor plate of the T-34 tank or the 75 mm plate of the KV-1 tank. This compelled the Luftwaffe to provide Hs 129 units with updates allowing installation of the 30 mm MK 103 cannon which possessed a higher muzzle velocity and a flatter shell trajectory than that provided by the MK 101. Some aircraft were also fitted with a 37 mm BK 3.7. Use of this larger weapon required the removal of the 7.9 mm machineguns. Both of these cannon were found to be effective against the softer sides and rear of the Russian tanks.
On 8 July, 1943, four squadrons of Hs 129s disrupted a Soviet surprise attack against II SS Panzer Corps near Belgorod. The anti-tank aircraft succeeded in scattering the Soviet tank brigade.
By the middle of 1944 the Luftwaffe realized the Hs 129’s performance was inadequate, as proved by excessive combat losses. Several experiments with higher power engines and different armaments proved unsuccessful. By the beginning of 1945 the Luftwaffe removed the aircraft from service.
Sources: Warplanes of the Third Reich, William Green, Doubleday and Company, Inc., Garden City, New York, 1972
The Henschel Hs 129, Profile Publication Number 69, J. R. Smith, Profile Publications Ltd., Leatherhead, Surrey, UK