(1) What are the current (a) actual and (b) required levels of air traffic controllers (ATC) at the (i) OR Tambo, (ii) Durban, (iii) Cape Town, (iv) Port Elizabeth and (v) East London airports; (2) whether there are any delays in let-down flight procedures as a result of ATC shortages; if so, (a) what are the economic costs of such delays and (b) what steps has been taken to overcome this problem?