Flying is one of the safest ways to travel and while you would have noticed a number of safety features on your flight, such as the emergency exits, there are a tonne of things you've probably never noticed.
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From the wing hooks to black triangles on the walls, these are some of the little-known plane features that are secretly keeping you safe...- The purpose of the hole is to allow pressure to equalise between the passenger cabin and the air gap between the panes. At high altitude the air is less pressurised and contains less oxygen; to make sure those on board don't lose consciousness, the cabin air on the inside of the plane is pressurised. This puts great pressure on the windows and the 'bleed hole' simply relieves some of this. The hole also prevents the windows from fogging up.
- Ever wondered why planes still have ashtrays in the toilets even though smoking on aircraft has been banned since the '90s? This is in case someone does light up while in the lavatory and has somewhere safe to stub out their cigarette rather than tossing the burning butt in the bin where it could catch fire. The Federal Aviation Administration (FAA) rules that toilet doors must be fitted with ashtrays as a legal requirement.
- All flight desks must carry an axe but have you ever wondered why? Retired airline captain Anas Maaz took to Quora and explained: "It is a fire-fighting device used to cut away cockpit panels and other aircraft areas if a fire develops inside them. The cutting allows the fire to be exposed, making it easier to aim the extinguishers to kill the fire off." Due to anti-terrorism regulations many airlines have replaced their axes with crowbars.
- The handles located at either side of the emergency exit are a safety measure for cabin crew to hang on and assist passengers in an emergency evacuation. If panicked passengers rush past while trying to escape, flight attendants could be shoved down the slide. The shoulder-length handles allow them to hang on while they man the doors.
- Those metal hooks you may have spotted sticking out of the plane wings are part of the evacuation system if aircraft is forced to land somewhere where you can't use the terminal boarding bridge. They are anchors for tying guide ropes which will help you safely off the slippery wing in an evacuation. If a life raft is deployed, the rope can be used to tether it and help passengers reach it.
The tiny black triangles on the walls of a plane indicate the position from which the wings can best be seen by staff from inside the aircraft. Writing on Quora, pilot Bruno Gilissen explains: "If there's any doubt about the position of the slats or flaps, the pilot can walk down the cabin, have a look through the window where the triangle is located, and see the numbers written on the slats/flaps."
Ever noticed a hum while waiting for the rest of the passengers to board a plane? The engines aren't powered up yet but the sound you hear is the auxiliary power unit, which provides electricity to the plane temporarily until it is ready for take-off. The small turbine powers a generator for electricity and a compressor for air pressure. The APU powers everything from the cabin lights to starting the main engine and is switched on before the first passenger boards so that everyone can sit in comfort before take-off.
- Plane windows are oval in shape because dangerous levels of stress would build up on the corners of square windows. A round window drastically reduces the chances of pressure building up and the likelihood of breaking. The narrowest part of the oval is designed to ensure the curve doesn't generate unsafe stresses in the surrounding material.
- As one Reddit user threeway explains, "you are able to unlock airplane lavatories from the outside. There is usually a lock mechanism concealed behind the no smoking badge on the door. Just lift the flap up and slide the bolt to unlock." This is used by flight attendants only if a child gets trapped or a passenger falls unconscious so don't be tempted to use this feature if you’re stuck waiting in line.
- Many airlines now equip their aircraft with defibrillators in case of a medical emergency. Qantas was the first carrier to introduce the defibrillators and all American airlines are required to carry them, while British Airways, Emirates, easyJet, Lufthansa and Virgin Atlantic also have them on board. After a British passenger suffered a cardiac arrest and died on a Ryanair flight in 2015, the low-cost airline announced that all of its aircraft would be equipped with the devices.