Type Two seat reconnaissance and light bomber
Engine BMW VI with a 2-bladed propeller
Dimensions Length 9,4  m , height 4,00 m ,  span upper 12,8 m, lower 11,4 m15,0 m , wing area 43,3 m2  ,
Weights Empty 1600 kg, loaded  2730 kg, max. take off weight    fuel 900 l
Performance Max.. speed 246 km/h , landing speed 90 km/h, cruising speed  195 km/h, range 200 ? km , endurance 6,0 h , service ceiling 6200 m  , climb to 1000 m 3,1 min., to 3000 m 11,4 min.
Armament
Type Werk.Nr Registration History
237 S-21, D-1205 Tested in Sweden 1925/1926. Back to Heinkel , minor modifications. To DVL later to Albatros GmbH. Stricken from register February 1932
The HD 33 was a two-seat biplane powered by an Armstrong Siddeley Puma inline engine. It first flew in 1928 but initial flight tests showed disappointing aircraft, so the plane was returned to its manufacturer and fitted with a BMW VI engine as well as a new radiator, thus being redesignated HD 33a. After flight tests in this new configuration, the aircraft was to be transferred to the flight test center in Lipitsk, but the German military abandoned the idea and the HD.33 remained a prototype only. Plans for a civilian version never materialized.