Page 143 - PPL-engelsk 2025

Human Performance

As you can see, there is very little time to act in the event of decompression at

40,000 feet—only 15–20 seconds.

At 18,000 feet, where pressure is halved, you may have approximately 30

minutes. At 36,000 feet, you might have only 30 seconds!

Put on your own oxygen mask first, then assist your fellow passengers or

colleagues. Afterward, the aircraft must descend as quickly as possible to an

altitude where oxygen is not required, below 10,000 feet.

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2.3.5 Other causes of oxygen deficiency

Oxygen deficiency can result from factors other than those mentioned above.

2.3.5.1 G-Forces

Another factor, G-forces, can prevent blood from flowing to the brain, causing

oxygen deficiency. Below, you can see a person experiencing 7G. Click the

image to watch the video.

https://www.military.com/video/specialties-and-personnel/pilots/7g-centrifuge-training/4816082930001

Fra: https://www.military.com/video/specialties-and-personnel/pilots/7g-centrifuge-training/4816082930001

At 3G, full control is still maintained. At 4G, the first warning signs appear, such

as loss of color vision (“Grey-out”).

With increased G-forces, vision is lost entirely (“Black-out”).

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 143