While traveling in planes, passengers may feel some strange actions and sounds during take-off, flight, and landing. Somebody may think that these sounds of rumbling, banging, and thumping mean that something is not fine, but actually, this is normal in aircraft.
Knocking before takeoff
It’s a usual order to hear knocks while boarding a plane and waiting for the take-off on your seat. This is the sound of the cargo loaded onto the plane below the cabin.
Most airlines make ground electric connections through the airport’s electricity when the plane is still on the ground. When the plane takes off, the pilot transports the electricity from the ground to the one which is found onboard which causes a flicker in the cabin lights for a moment.
Thumps and whir after takeoff
When the plane starts leaving the ground the pilot pulls up the wheels and inserts them into the body of the plane and closes the flaps. These may cause a sound of thumps. The sound of whir is caused by the pilot opening the boards of the wings, which is necessary for the plane’s take-off. Also, both of these procedures are part of a process called “cleaning up the plane” to make it streamlined for flight.
All airlines use chimes in different ways, according to John Cox, a retired pilot, one chime means a precaution from the pilot to flight attendants of turbulence or the flight attendant asking the pilot if he wants a cup of coffee. Two chimes mean that the plane is approaching 10’000 feet. Three or more chimes mean a serious order as a very sick passenger or precaution of impending rough air.
When the plane starts to bevel the engine’s noise starts to reduce because of the gradual decrease of the engine’s acceleration. To land the plane safely flight spoilers are activated which includes long-boards that have to be lifted up to increase drag. All of these actions cause the feeling of vibration and rumble.