Here is why passengers on Indian flight were bleeding from nose and ears

A cockpit mix-up left more than 30 passengers on an Indian plane bleeding from their ears and noses Thursday after the crew forgot to flick a switch regulating cabin air pressure.

The Jet Airways flight carrying 166 passengers landed back in Mumbai and those affected were given medical attention while alternative flights were arranged, Jet Airways said.

The incident of ear and nose bleeding are associated with air pressure changes within the cabin.

Outside pressure drops dramatically as plane gains altitude and it becomes impossible to breathe outside the cabin at the cruising altitude of jets which generally varies from about 33,000 feet to 42,000 feet.

Air plane cabins are pressurized to maintain a constant cabin altitude of 8500 feet in order to enable the passengers to breathe when the outside air pressure is low.

A lack of oxygen can lead to hypoxia, a condition where the amount of oxygen reaching the body tissues gradually drops.

Oxygen masks installed in the ceiling are used in the case of an loss of cabin pressure.