JAN MAYEN HOMESITE, EDITED BY THE JAN MAYEN CREW

Air operations at Jan Mayensfield can be challenging due to difficult weather conditions like low visibility or Karman wind. Karman wind causes sudden dramatic changes in wind direction and force. Under certain atmospheric conditions lee-waves and eddies develope a Karman vortex street in the wake of Jan Mayen.


Karman created by Beerenberg 20/3/2001	Karman simulation	Karman wind created by Beerenberg. (2277m)

The Karman vortex street may extend several hundred kilometer downstream from the island. Wave lengths range from 1-15 km and the diameters of the eddies are of the order 25 km. The lee-waves and eddies are caused when airflow is diverted by Jan Mayen's isolated conical mountain Beerenberg, 2277 m above sea level. Eddies are normally generated in situations with a shallow inversion layer intersecting the mountain below 1800 m. The period of the vortex shedding depends on wind speed and stratification and ranges from 25-100 minutes. The eddy shedding has also been recorded on the island as periodic oscillations in air pressure and shift in the wind direction.

In 1991 a C-130 nearly crashed due to a sudden Karman shift just after takeoff.

Jan Mayensfield was established in 1961 due to the lack of a useable harbour in combination with bad weather conditions at Jan Mayen. Every second month the station gets supplies by plane. Crew-shifts are also done by plane. Today most of the air transport is done by The Royal Norwegian Air Force and their fleet of Locheed C-130 Hercules. During the first years aircrafts like Consolidated PBY Catalina , Douglas DC4 Skymaster, Grumman A16 Albatross and Douglas DC6B were used. Jan Mayensfield is important in medevac and rescue operations, both for the Jan Mayen station and for ships that need assistanse. When needed the airfield also serves as a base for research operations.


Aircrafts 1960-2006	View, Jan Mayensfield	Airfield buildings	Low-pass