Planes have been built and repaired in Halli, Kuorevesi, which nowadays is a part of Jämsä, since the year 1940. The aviation industry has provided a living for people in the area through highs and lows. The industrial area of Halli was created by two factories, Veljekset Karhumäki Oy and Valtion Lentokonetehdas.

The airplane industry also brought the Air Force flight depot and test flight section to the region. From the start of the new millennium, the factory name has been Patria. The Air Force test flight centre and technical school operate in the garrison.


The aviation hobby of the brothers Karhumäki, Niilo, Valto and Uuno began in the 1920s in Keljo in Jyväskylä. Niilo and Valto Karhumäki began building their first plane Karhu 1 in 1924 with Eemil Kankaanpää and Toivo Hovinen. In the 1920s and -30s the brothers' business comprised of building planes, flying members of the public, flight training and aerial photography. The general partnership Veljekset Karhumäki was founded in 1933.

The next year, the brothers began doing maintenance and repair work for the Air Force. In spring 1938, Marshal Mannerheim made a surprise visit to the airplane workshop in Keljo. Later that same year, the engineers Koskiala and Kuusinen suggested that the company should expand and relocate from Keljo to a more suitable site.

The general partnership was changed to Veljekset Karhumäki Oy (Inc.) in 1939. The flying Karhumäki brothers held the majority of the company shares

Copy Milla Sinivuori-Hakanen
Pictures Aviation Museum of Hallinportti, Jyrki Laukkanen, Patria Aviation Oy and Veljekset Karhumäki Oy

Sources
Björklund Nils G.: Valmet. Asetehtaiden muuntuminen kansainväliseksi suuryhtiöksi
Karhumäki Niilo: Karhunahas
Kuoreveden kirja
Lentovarikon historia 1918 - 2000
Suomalaista lentokoneosaamista 80 vuotta
Tervonen Ismo: Veljekset Karhumäki Suomen ilmailun pioneereina 1924 - 1956