The world's only operational global navigation satelllite system (GNSS) precision approach guided its first passenger-carrying aircraft to touchdown on 29 October at a remote airport in Norway.

A Bombardier Dash 8-100 of SAS subsidiary Wideroe carried out the inaugural approach to runway 04 at Brønnøysund, landing at 10:40 local time in fair weather.  

Known as SCAT-1 (special category one), the  system is a differential GNSS precision approach with ground-based augmentation.

Already approved by the Norwegian Civil Aviation Authority and certificated by the European Aviation Safety Agency, the system will, over the next few years, be installed at 24 of Norway's local airports where terrain or steep glideslopes make the use of instrument landing systems (ILS) impossible, says Steinar Hamar, the SCAT-1 progamme manager at Norwegian airports operator Avinor. Many of these are "stolports" with 800m runways.

Navigation manager at Wideroe Jens Gjerlev says that the impetus to improve approach safety became irresistible following the controlled flight into terrain accident to a Wideroe Dash 7 on approach to Brønnøysund in May 1988 that killed all 36 on board.

Work to develop a GNSS-based precision approach system began in 1997. Research, trials and winning institutional approval took far longer than anticipated, says Gjerlev.