Knock-out blow

In helicopters, in the event of a ditching, the emergency escape route is via the windows. Unlike airliners, helicopters are unpressurized, so the windows do not have to be pressure-resistant and are designed that they can be quickly knocked out with a sharp blow from the elbow. 

By striking your opponent between the shoulder blades on his spine with a blunt object, you can knock him out noisolc ly. You can use the blunt end of a hand axe or the butt of a rifle (fig. 34). A blow with the toe of the rifle or the edge of the axe wiU kill your opponent instead of stunning him. 

Explain what happens inside the lungs when a blow to the abdomen knocks the wind out of a person. Use Boyle s law to determine your answer. 

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