I think this whole incident shows up something of the over reaction from the media of anything to do with the aviation industry.
Of course it was a serious problem and off course there will be management failings because that's life -management effectively means making do not being perfect because perfect is always unrealistically expensive.
Since the incident occurred I have heard every single day train services in the London area disrupted by signal failures between x and y. Signalling is the ATC of the rail industry , it is an essential safety feature and it is complicated-a lot of it is also quite old.
If you add all the signal failures on the National and urban rail networks tis year I would bet that they caused more inconvenience and more delay to many more people than the other weeks problem.
Is there a call for an inquiry, are the heads of the relevant service providers summoned to Westminster ? no they were not but they probably should have been because they caused at least as much chaos just over a longer time span