by Horst Zoeller, 1996 - 2020, 67th Edition, 22 Nov 2020

Junkers H21

see also:  Junkers H21 Production List  

2 seater highlever monoplane Surveyer, F/F 12 Jun 1923, about 120 built
developed by Junkers Flugzeugwerke in Dessau, designed by Zindel, Bruno Starke (undercarriage), Haseloff (fueselage) and Freundel (tail unit)

Historical Background:

Following to the design of the Junkers J20, Zindel headed for the landbased reconaissance aircraft, which had to be developed for the Soviet Army. This design was developed under the designator J21 since February 1923. The design is based on the Junkers T19 high lever monoplane. The first prototype (c/n 354) was finished at Dessau in June 1923 and was first flown by Zimmermann during this month. Problems arised from the wing construction of the prototype, so the wing area was reduced by a quarter of its original size. Nevertheless, Junkers was unable to fullfill the contracted performance with his J21. In Dessau in accordance with the T19 designator the designator for that type was changed to Junkers T21, when the developement was finished.

Later Ju21 Design with modified tail (Fili)

The production plans were transfered to
Fili, where the serial production was initiated under the designator Junkers Ju21 during August 1923. Also the two Dessau built prototypes were transfered to Russia. A total of 120 Ju21s were produced at Fili during 1923/24. As the performance of that aircraft was not satisfying the Russians, Junkers modified a few aircraft with his Junkers L2 and Junkers L5 engines. But also these engines were unable to achieve the requested performance. A serial production was also intended for Dessau under the designator Junkers H21, but due to the bad performance, this plan was later abondend. Some sources mention a H21 prototype, which should have been built at Dessau (c/n 802), but this is not ensured. Only two J21s were definitely built in Dessau, while all other aircraft were built at Fili.

Technical Data


year engine length
in m
in m
wing area
im sqm
net weight
in kg
in kg
seats speed
in km/h
in km

J21 prototype
J21 serial line


BMW IIIa (136kW)






1 pilot+
1 observ.



J21 Designators:

  • J21, initial Junkers prototype
  • T21, Junkers Marketing Designator for German market 
  • H21, Junkers Production Designator in Germany for Russian J21s 
  • Ju21, Fili Production Designator for J21s 



  • None

introduced Jul 1996, transfered Jun 2017
contents last updated 12 Jan 2003