An IT contractor was sentenced to 15 months in jail after it was revealed he sold stolen IT equipment from the National Air Traffic Services control centre in Swanwick.
Andrew Woffindin, who had high-level security clearance, sold computers that contained information that could pose a risk national security in the wrong hands.
He pleaded guilty in July to selling the stolen equipment and was this week was jailed for selling £58,000 worth of kit, including laptops and mobile phones.
According to the Mirror.co.uk judge Peter Henry branded Andrew Woffindin "a threat to national security" because he sold computers over the internet that contained secret data on military and commercial flights.
He was exposed when a missing laptop was spotted on an internet auction site
But Chris McIntosh, CEO at security supplier Stonewood Group, said it was highly unlikely that national security could have been compromised in this case because top secret information must be protected by CESG-approved encryption products.
"This means that if a laptop or USB is stolen, then the data on it cannot be accessed without the encryption key. The only way that national security would have been put at risk is if Woffindin also had access to and was selling the encryption keys."