Complex sentence: The town has a small airport, used only by light aircraft, but until the 1970s when they stopped operating piston engined airliners such as the Douglas DC-3, it was a refueling stop for South African Airways between Cape Town and destinations to the north.
Split into simpler sentences: The town has a small airport, used only by light aircraft. Until the 1970s when they stopped operating piston engined airliners such as the Douglas DC-3, it was a refueling stop for South African Airways between Cape Town and destinations to the north.