Anyone who has travelled through an airport has personally experienced the strictness of airport security.
There are rigid rules about what you can and cannot take on a plane, both in the hold and the cabin.
Not only do you have to separate your liquids from your hand luggage, but you’re also banned from taking many items on board altogether.
Passengers are prohibited from carrying weapons, or anything that could be used as a weapon, on commercial flights.
Flight secrets: Commercial aircraft each carry a dangerous tool in the cockpit
Each airplane accommodating more than 19 passengers must be equipped with a crash axe
But there is at least one exception to this rule – and it’s found in the cockpit of the plane.
According to the Federal Aviation Authority (FAA), all commercial aircrafts must carry an axe in the cockpit.
FAA Section 91.513 states: “Each airplane accommodating more than 19 passengers must be equipped with a crash axe.”
The axe is installed as a fire fighting device, so crew can cut away cockpit or other panels in the event of an electrical fire.
Flight secrets: An axe is stored in the cockpit for crew to break down door panels in case of fire
There is no specific legislation in the the Civil Aviation Authority (CAA) – the FAA’s UK counterpart – about axes on planes.
But the CAA concedes “many” aircraft carry them for emergencies.
A spokesperson told Express.co.uk: “There is no specific regulation requiring an axe to be carried in cockpits.
“Many aircraft have a small axe fitted somewhere in the cockpit to allow the pilots to break the windscreen if necessary during an emergency evacuation.”
Flight secrets: The axe is stored in the cockpit for crew to use in emergencies
The captain of doomed Germanwings Flight 9525 reportedly tried to break down the cockpit door with an axe from the outside before the plane crashed into the French Alps.
Prosecution sources in France said Captain Patrick Sonderheimer used “an onboard axe” – part of the Airbus A320’s safety equipment – as it flew from Barcelona to Dusseldorf.
He had been locked out of the cockpit by his co-pilot Andreas Lubitz.
Prosecutors investigating the crash which left 150 people dead said Lubitz, who had been suffering from depression, had “deliberately” destroyed the plane.