Eidgenössische Konstruktionswerkstätte (K+W)
A Swiss army workshop founded to repair artillery in 1863 built the country’s first home-grown military aircraft in 1916, then licence-built Dewoitine fighters before handing aviation to Emmen.
Eidgenössische Konstruktionswerkstätte (K+W): the company and the aircraft that made its name
An artillery workshop in Thun
The federal works at Thun began life in 1863 as the Eidgenössische Reparaturwerkstätte, a repair shop set up on the initiative of General Hans Herzog, the army’s inspector of artillery. In 1874 it became the Eidgenössische Konstruktionswerkstätte, the federal construction workshop, known by the initials K+W. For half a century its business was guns, carriages and military equipment. Aircraft arrived only with the First World War, when neutral Switzerland found it could no longer simply buy what it needed abroad.
Haefeli’s aeroplanes
The man who turned K+W into an aircraft maker was the engineer August Haefeli. His first design, the Häfeli DH-1, was delivered in April 1916, and it was followed by a family of two-seat reconnaissance biplanes: the DH-2, the long-serving DH-3 and DH-5 in several versions, and the Militär-Apparat series MA-6, MA-7 and MA-8. From 1925 K+W built French Dewoitine fighters under licence, including the D.26 and D.27, and from 1933 it shared production of the Fokker C.V-E with the Dornier works at Altenrhein.
Into RUAG
Military aircraft work left Thun for the new federal aircraft factory at Emmen between 1940 and 1943, and K+W went back to being an arsenal. In the mid-1990s it was renamed Schweizerische Unternehmung für Waffensysteme, in September 1998 it became a joint-stock company, and by 1999 it had been absorbed into the new RUAG group, where the old Thun works formed the core of RUAG Defence.
Eidgenössische Konstruktionswerkstätte (K+W) in numbers
The company
- In short
- Founded 1863
- Federal repair workshop in Thun, founded at the urging of General Hans Herzog
- Renamed Konstruktionswerkstätte (K+W) in 1874
- Merged into RUAG, 1998–1999
Production
- Best known for
- Häfeli DH-3, DH-5
- Häfeli DH series, from 1916
- Licence Dewoitine D.26 and D.27 fighters
- Fokker C.V-E with Dornier Altenrhein, from 1933
Today
- Now
- Part of RUAG
- Aircraft production moved to Emmen, 1940–1943
- Thun works became the core of RUAG Defence
The numbers
- Dewoitine D.26 built
- 11
Every notable Eidgenössische Konstruktionswerkstätte (K+W) aircraft
Photos: Wikimedia Commons (Public domain)
| Aircraft | Role | First flight | Built | Status | Note |
|---|---|---|---|---|---|
| Häfeli DH-1 | Reconnaissance biplane | 1916 | Retired | First delivered April 1916 | |
| Häfeli DH-3 | Reconnaissance and training biplane | Retired | Built in several variants | ||
| Häfeli DH-5 | Reconnaissance biplane | Retired | Built in several variants | ||
| Militär-Apparat MA-7 | Military biplane | Retired | One of the MA-6 to MA-8 series | ||
| Dewoitine D.26 | Fighter trainer (licence) | 11 | Retired | French design built under licence | |
| Dewoitine D.27 | Fighter (licence) | Retired | French design built under licence | ||
| Fokker C.V-E | Reconnaissance biplane (licence) | Retired | Co-produced with Dornier-Werke Altenrhein |
Eidgenössische Konstruktionswerkstätte (K+W) aircraft in the world’s air forces
1 air forces in the Order of Battle fly or flew Eidgenössische Konstruktionswerkstätte (K+W) types. 0 of them still have one in service.
| Air force | In service | Formerly flown |
|---|---|---|
| Swiss Air Force | Morane-Saulnier MS.406 / EKW D-3800, D-3801, D-3802, D-3803, EKW C-3603 and C-3605, EKW C-35, Häfeli DH-3 and DH-5 |
Where Eidgenössische Konstruktionswerkstätte (K+W) built, who led it, what it achieved
Factories
- Federal works, Thun · Thun, canton of Bern — Aircraft built here until production moved to Emmen, 1940–1943
People
- Hans Herzog · general, inspector of artillery — Initiated the workshop in 1863
- August Haefeli · aircraft designer — Designed the DH series from 1916
Eidgenössische Konstruktionswerkstätte (K+W), year by year
Federal repair workshop founded in Thun
Renamed Eidgenössische Konstruktionswerkstätte
First Häfeli DH-1 delivered
Licence production of Dewoitine fighters begins
Fokker C.V-E production with Dornier Altenrhein
Aircraft production begins moving to Emmen (to 1943)
Converted into a joint-stock company
Absorbed into RUAG
Before and after Eidgenössische Konstruktionswerkstätte (K+W)
Everything people ask about Eidgenössische Konstruktionswerkstätte (K+W)
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Around Eidgenössische Konstruktionswerkstätte (K+W)
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Verified 2026-10-03.