Heinkel HD 37
Heinkel · German Reich · first flew 1931 · fighter
The Heinkel HD 37 was a German single-seat biplane fighter designed in the early 1930s that was exported to the Soviet Union, where it was produced under licence as the Polikarpov I-7. It was a capable aircraft for its era with a powerful liquid-cooled engine.
Recognition (WEFT)
| W — Wings | Mid-mounted, straight |
|---|---|
| E — Engines | 1 × piston, nose-mounted |
| F — Fuselage | 6.95 m fuselage |
| T — Tail | Conventional |
WEFT is AircraftIQ's four-point recognition method — how it works.
Spot it by:
- German export biplane fighter sold to Soviet Union
- Built under licence in USSR as I-7
- Single-seat parasol or biplane with BMW VI engine
Single-bay biplane with a smooth inline engine installation (BMW VI), fixed undercarriage with trouser fairings, and a single open cockpit. The liquid-cooled engine gives it a longer nose than radial-engine contemporaries.
Specifications
- The Heinkel HD 37 has a length of 6.95 m (23 ft).
- It has a wingspan of 10 m (33 ft).
- Its maximum speed is 290 km/h (180 mph).
- Typical crew: 1.
Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.
History
Heinkel produced the HD 37 as an export fighter at a time when Germany was rebuilding its aviation industry covertly. The Soviet Union purchased examples and a licence to build the type, which entered Soviet service as the I-7. This cooperation was part of the broader secret German-Soviet military technology exchange of the Weimar period. The I-7 served briefly with Soviet forces before being replaced by indigenous designs.
Variants
The HD 37 was exported to the Soviet Union as the primary customer. The Dux factory-built version in the USSR was essentially identical, designated I-7. The manufacturer listed includes the Dux Factory as a co-manufacturer for the Soviet-built examples.
Where you'll see it
Operated by the Soviet Air Force as the I-7 in small numbers during the early 1930s. Quickly superseded by more capable Soviet-designed fighters. German examples remained few.
Related aircraft
AircraftIQ — the aircraft field guide: 4,893 recognition guides, live overhead identification, works offline.