Terrifying new crime that's hit 1,100 flights which experts fear could lead to deadly plane crash

A dangerous crime is plaguing the flying industry, increasingly concerning pilots, airlines and experts.

Incidents of GPS spoofing have spiked from only dozens per day in February to over 1,100 in August - a 400 percent increase, according to an OPS Group report.

GPS spoofing occurs when a fake radio signal is used to interfere with and override a legitimate one. It is a cyberattack and is used as a warfare tactic.

Civilian flights were the primary targets of these kind of attacks, but now commercial pilots are seeing a rapid increase in these confusing GPS signals that 'could be extremely dangerous,' American Airlines Captain Dan Carey told The Wall Street Journal .

Ken Alexander, the Federal Aviation Administration's chief scientist for satellite navigation, said at a pilot union forum: 'If we lose an airplane because of workload issues because of these problems we're encountering, compounded with an emergency, that is going to be a horrendous event.'

Experts warn that flights are at risk for spoofing beyond war-torn areas such as Ukraine and the Middle East, but occurrences are still rising in those places as well.

Pilots have reported false warnings, reset clocks and wrongly-directed flight paths - these can last for a few minutes or for the entire flight.

It can take planes off their intended tracks and cause them to miss their designated landing spaces.

Executive Director of the European Aviation Safety Agency Florian Guillermet told The Wall Street Journal: 'The risk is growing in terms of the number of occurrences.'

The OPS group reported that the highest number of interferences has been up to 1,350 flights in one day.

In April, two Finnish flights were forced to turn around due to Russian GPS manipulation.

A similar incident happen in August when a United Airlines pilot started seeing coordinates that did not match up with their actual location while flying through Asia to Newark Liberty International Airport, according to The Wall Street Journal.

Even after the flight left the spoofed area - south of Ukraine - the discrepancy lingered for the rest of the flight. The GPS system shows the flight was over the Atlantic Ocean when it had already arrived in Newark.

Carey experienced the stress of being targeted by GPS spoofing first-hand. The pilot received a 'pull up!' signal during a March flight over Pakistan. This kind of alert tells pilots that they are about to collide with something.

He knew he was too high off the ground - 32,000 feet in the air - for this signal to be accurate.

American Airlines and United Airlines are among those who have been impacted by this issue.

They are figuring out a new procedure for pilots to reset circuit breakers in cockpits when they notice something is wrong.

But plane manufacturers like Boeing have been reluctant to implement this kind of procedure because it could lead to electrical issues on the flight.

Retired United Airlines captain Christopher Behnam told The Wall Street Journal that while flying over the Middle East, he often experienced this kind of interference and in low-visibility situations, it can be 'very, very, very alarming.'

'We are trained for these things, so you stay calm and you just follow the procedure,' he said.

Pilots have reportedly observed that the first sign of GPS spoofing is when a clock starts running backwards.

Ken Munro, founder of cybersecurity firm Pen Test Partners, said during a presentation at a DEF CON hacking convention: 'We think too much about GPS being a source of position, but it's actually a source of time.'

He later said that he's seen a major airline have a cockpit's clock get set ahead by several years during a spoofing incident.

A GPS spoofing workgroup made up of 450 participants is working to resolve this problem and get to the bottom of the issue.

United Airlines, American Airlines, Aer Lingus, Turkish Airlines and Alaska Airlines are some of the major airlines involved.