The Orlogsværftet J.1 Jäger was a secret Danish indigenous fighter project developed at the Royal Naval Dockyard (Orlogsværftet) in the late 1930s.
The project began when political circumstances threatened Denmark’s ability to import modern fighters, particularly from Italy.
In response, engineers at Orlogsværftet quietly initiated the design of a fully indigenous aircraft.
The J.1 was conceived as an all‑metal, monocoque, single‑seat fighter, reflecting contemporary European design trends.
Its exact specifications are unknown, as the project never advanced beyond preliminary design studies.
The initiative ultimately came too late.
Before a prototype could be constructed, Denmark was invaded by Germany on 9 April 1940.
All development ceased, and no complete documentation is known to have survived.
Today, the J.1 Jager remains a little-known footnote in Danish aviation history — a promising but unrealised attempt to create a domestic fighter aircraft on the eve of World War II.
