BAS currently runs a fleet of Sno-Cats – a tracked vehicle that has been used in Antarctica since the the Commonwealth Trans-Antarctic Expedition (1955-58) – and a fleet of snowmobiles that are extensively used at the BAS stations and at remote Antarctic field locations.
Sno-Cats are used for carrying personnel and towing sledges of up to eight tonnes. Powered by Detroit Diesel or Cummins 6BT and QSB engines of about 170 horsepower, these drive through Allison automatic transmissions to four tracks that are steered by turntables to which the axles are fitted.
BAS operates snowmobiles (also known as skidoos) which are simple to ride with just a thumb throttle and a brake. They have a fully automatic transmission and a track underneath with skis at the front to steer. These smaller vehicles are used for personal transport and for towing Nansen sledges.
Snowmobiles can attain speeds of up to 50mph on smooth snow powered by a Rotax 503 engine.