An Azores Airlines de Havilland Dash 8-400 made an emergency landing in Funchal after a sudden loss in cabin pressure. The plane was due to land in Funchal, completing flight S4-160 from Ponta Delgada. There have been no reports of serious injury, but a pregnant woman was seen by medical staff upon arrival.

What happened?

The aircraft in question, registration CS-TRE, was carrying nine passengers from São Miguel Island in the Azores to Funchal on the island of Madeira. The aircraft was around 200 nautical miles northwest of the island when it experienced a sudden drop in cabin pressure. The crew reacted by performing an emergency descent to 10,000 feet from the cruising altitude of 25,000. The descent took just five minutes.

This is the standard response to a drop in cabin pressure. The plane continued at 10,000 feet and landed safely, almost on time, in Funchal just under one hour after it descended to 10,000 feet.  While there have been no reports of anyone being seriously injured by the sudden change in pressure, one of the nine passengers was pregnant and sought medical advice. It is thought this is just a precautionary measure.

Azores Airlines radarbox
The plane managed to fly for an hour at 10,000 feet before landing safely in Funchal. Photo: RadarBox.com

Whatever caused the loss in pressure was clearly not enough to ground the plane for any length of time. According to RadarBox.com, the de Havilland Dash 8 is only 11 years old and has now left Funchal and is airborne again. However, the plane is still traveling at 10,000 feet and is on a heading suggesting it may well be returning to the Azores Airlines base in Porta Delgada for repairs. The airline has not confirmed this and, at the time of publication, had not responded to a request for comment.

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Cabin depressurization

Sudden cabin depressurization is not a totally uncommon incident and usually does not result in fatalities or crashes. The loss of pressure can be caused by a range of factors including human error, such as failing to seal doors correctly, or material wear and tear. However, that doesn’t mean it can’t cause serious injury. The biggest health concern is a sudden loss of oxygen, resulting in dizziness, trouble breathing, and in extreme cases, loss of consciousness or even death.

Cabin oxygen masks
Time of useful consciousness significantly decreases with altitude. Photo: Getty Images

However, a more likely issue is pressure damage to the eardrums, leading to ear damage. Passengers may also experience nausea and dizziness, but this usually fades once at a lower altitude. Generally, air masks will be made available to ensure oxygen, and this should prevent any major injuries.

The incident from this morning appears to have caused no injuries at all. Reports are suggesting one pregnant lady was seen by medical staff, but it was not serious. Pregnant women are more likely to have problems with pressure in their ears, so the sudden change may affect them more severely.

Have you ever experienced sudden cabin depressurization? We’d love to hear about your experience if you have.