More than 13 years ago, a Boeing aircraft crashed in a hilly terrain in Greece snuffing out 121 lives. A year later, investigators concluded that omissions in controlling cabin pressure was a key reason for the crash. Extreme case in 2005, a Helios Airline flight crashed into a mountain after the pilots lost consciousness from hypoxia.
One of the pilots said that generally, an aircraft is pressurized to 8,000 feet so that the pressure is adequate for the human body. Normally, a plane flies at an altitude of around 35,000 feet.
De-pressurization could even result in hypoxia for the people on board. Hypoxia or lack of adequate oxygen supply for the human tissues, can cause various problems, including deterioration in a cognitive abilities.
Loss of cabin pressure could result in hypoxia or the deprivation of oxygen. Oxygen deprivation is also the cause of headaches, nausea, and nosebleeds. A sudden drop in air pressure can be fatal for people with pre-existing conditions such as hypertension and cardiac anomalies . There is a cavity in our oral and nasal passages and sudden change in air pressure of the surroundings negatively impairs the internal air pressure maintained in these cavities, thus causing bleeding through nose, ears or mouth. At the same time, the sudden drop in the pressure and lack of oxygen supply to the brain can also cause strokes, paralysis or convulsions in some people.
Drop in air-pressure in the surrounding affects people differently. While it usually causes heaviness in the head, dizziness and drowsiness in some, it can also be fatal for people with high blood pressure and a history of heart attacks. The five passengers suffered “barotrauma” of ear, which is caused due to a change in air pressure.
Several passengers on a Jet Airways Mumbai-Jaipur flight suffered nose and ear bleeding on Thursday morning as the pilots forgot to switch on the system to maintain cabin pressure, the DGCA said. “The 9W 697 Mumbai-Jaipur flight was turned back to Mumbai after take off as, during the climb, crew forgot to select switch to maintain cabin pressure. This resulted in the oxygen masks dropping. Thirty out of 166 passengers experienced nose and ear bleeding, some also complained of headache,” deputy director general, Directorate General of Civil Aviation (DGCA), said. The crew has been taken off duty and Aircraft Accident Investigation Bureau (AAIB) has started an investigation, DGCA added. Ministry of Civil Aviation has requested DGCA to file its report immediately on the issue. The passengers are being treated at Mumbai airport. In a statement, Jet Airways said the B737 aircraft landed normally in Mumbai. “All guests were deplaned safely and taken to the terminal. First aid was administered to few guests who complained of ear pain, bleeding nose etc. The flight’s cockpit crew has been taken off scheduled duties pending investigation. The airline is making alternative flight arrangements for guests on this flight. Jet Airways regrets the inconvenience caused to its guests.” Several passengers posted images from inside the plane, that showed that oxygen masks had been deployed due to the low cabin pressure