London Air Traffic: Computer Breakdown (Hansard, 21 October 1986)

§ Lord Mackie of Benshie
My Lords, I beg leave to ask the Question standing in my name on the Order Paper.
The Question was as follows:
To ask Her Majesty's Government what were the results of the breakdown of the computers governing the air traffic control system at London airports on Monday, 6th October, why the breakdown occurred, and what steps they are taking to ensure that it does not happen again.

§ The Parliamentary Under-Secretary of State, Department of Transport (Lord Brabazon of Tara)
My Lords, on Monday, 6th October the National Air Traffic Service's London air traffic control centre had to transfer to manual operations when its computer could not handle excess data that morning. Restrictions on traffic had to be imposed for some three hours, resulting in considerable delays at Heathrow and Gatwick. The National Air Traffic Service has now modified the computer programme.

§ Lord Mackie of Benshie
My Lords, I thank the noble Lord the Minister for his reply. However, I wonder whether the noble Lord is showing sufficient concern over this matter. It is very disturbing indeed that, with one breakdown or one overloading of a computer programme, we had a stoppage of flights, certainly from Scotland. The noble Lord did not answer my Question as to how many flights were cancelled or delayed. This has immense implications. Surely there must be a backup system. Furthermore, it has implications for our defence. If one computer breakdown can result in this sort of delay, surely the Government must take that very seriously and look into all forms of backup and indeed a reorganisation of the whole affair.

§ Lord Brabazon of Tara
My Lords, perhaps I may assure the noble Lord and the House that we take this matter very seriously. I am sorry if the noble Lord's flight from Scotland was delayed. Obviously, in a situation such as that, it is easier to delay short-haul flights than to delay long-distance flights. However, we should be encouraged by the fact that the manual operations were able to take over. They operate at roughly only half the capacity of the computerised operations. Certainly in the defence situation, if the system had to go over to manual, that is what would happen.

§ Lord Carmichael of Kelvingrove
My Lords, does the noble Lord remember that during the passage of the Airports Bill considerable concern was expressed about the role of air traffic controllers, and particularly the hours that they work? After the events of the 6th of this month at the London airports, it strikes one that the stress, strain and tension on air traffic controllers is perhaps even greater than we had thought when we discussed the matter during the Airports Bill.
Will the noble Lord look carefully at the whole question of the hours and the manual manning by air traffic controllers, and perhaps even consider giving a higher staff complement than is normal because of the incredible importance of this matter? Had anything happened in the London area that day or had there been an accident because of the fatigue of the air traffic controllers, the result could have been quite horrendous. With the department, will the noble Lord look at the role of the manual operations of air traffic controllers?

§ Lord Brabazon of Tara
My Lords, obviously I shall draw the remarks of the noble Lord, Lord Carmichael, to the attention of my right honourable friend. However, I can assure the noble Lord that at no time whatever was aircraft safety endangered. It was a controlled handover to manual from computer operation and, though I accept that the results were inconvenient to a great many people, in that respect it was extremely successful in that the manual operation was able to take over from the computers, though admittedly not at the same capacity. Great credit is due to the air traffic controllers.

§ Lord Mackie of Benshie
My Lords, would the situation have been quite so easy if the breakdown had occurred when the heavy overnight traffic was coming in an hour earlier?

§ Lord Brabazon of Tara
My Lords, I am afraid that I cannot answer that question specifically, but I am assured that, even if there was a complete breakdown rather than a controlled shutdown, as this was, at no time would aircraft safety be endangered.