The British Airports Authority says that despite the disruption from Iceland’s volcanic ash cloud which closed UK airspace for several days, cargo tonnage in April was up 6.2 per cent on last year reflecting what it said is the underlying strength of the air cargo business. Passenger traffic slumped by 22.7 per cent last month as a direct result of the ash cloud. Worst hit were Southampton and Edinburgh airports which saw passenger numbers tumble by 27 and 26 per cent respectively. Heathrow and Stansted were both down 21 per cent.