Business Secretary Vince Cable has blamed the technical failure behind last week's airspace chaos on a lack of IT investment.
Airspace above London was closed to all traffic for around an hour on Friday following a major system failure at Nats, the UK's main air traffic control centre in Swanwick.
And Cable told the BBC's Andrew Marr that Nats' IT systems were "ancient" and likely to crash because the organisation was "skimping on large-scale investment".
He added:"We have to maintain a high level of capital investment."
There are plans to boost the funding for the systems, with Nats pledging to up spending to575 million over the next five years.
However, Cable told the BBC's Andrew Marr that Nats had decided to forego capital investment over many years, leading to the troubles seen on Friday, when many of London's major airports came to a standstill.
The problems were initially thought to be down to a power outage, butNats' chief executive Richard Deakin has since revealed the outage was down to a faulty line of code in one of its systems.
"The challenge is that we have around 50 different systems at Swanwick and around four million lines of code," he told theBBC."This particular glitch was buried in one of those four million lines of code.We haven't seen that particular issue before."
ANats spokeswoman told IT Proat the time of the outage on Friday:"All we have at the moment is a statement saying it's a technical failure."
"We're certainly working to discover the root of it and we have rectified it now and there will be a full and robust investigation."
The Swanick air traffic control centrecontrols 200,000 square miles of airspace above England and Wales and has had experienced outages in the past, although it is not clear whether these were down to the same problems experienced on Friday.
The affected systems were back live by around 4pm on Friday and some flights were departing at Heathrow and Gatwick, others were set to remain grounded until at least 7pm due to the problem.
How Heathrow appeared on Google Maps on Friday evening
The BBC cited one source as describing the issue as a glitch with the computer system that calculates in which order incoming and outbound flights to and from London should land and take off.
An independent inquiry into the glitch is to be launched by the UK's Civil Aviation Authority, which will appoint a chair to lead an investigation into Nats' handling of the issue and how successful the organisation has been at improving IT following previous problems.
This article was originally published on 12/12/14 and has been updated (most recently on 15/12/14) to reflect new information available since publication.
