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  1. ITV Report

Shoreham Airshow Crash: How does G-force affect the body?

  • Reporter Juliette Fletcher spoke to former pilot Sue Adcock about the affect of G-force on the human body:

The Shoreham Airshow crash pilot Andrew Hill was adamant throughout the trial that he had no recollection of the crash.

His defence argued that he was suffering from “cognitive impairment” brought on by hypoxia - a lack of oxygen in the blood - that might have been due to the G-force he was experiencing.

  • What is G-force?
RAF aircrew undergoing new simulator training to learn to deal with G-force. Credit: Thales

G-force is a measure of how much force someone is experiencing, relative to the normal force of the Earth’s gravity.

For example, at 5G your body weighs five times heavier than it would do normally.

Looping and rolling manoeuvres like those performed by fast jet pilots drastically increase the G-force they experience.

They undergo intensive training to learn to deal with the effects of high G, using breathing techniques and specialist equipment to increase their tolerance.

  • How does it affect the body?
G trousers are worn over a flight suit to help pilots deal with high G manoeuvres.

G-force has a number of effects on the body, the most dangerous being that which it has on your blood.

The same forces that make you feel heavier pull your blood lower in your body, away from your brain.

The result is that, under high G-force, people often pass out.

Pilots use breathing techniques, engaging their leg muscles and their core, to try and keep blood more evenly spread throughout their body.

Fast jets also use something called a G-suit; a pair of pneumatic trousers, plumbed into the aircraft via an air hose.

This suit inflates automatically when the pilot undergoes high G manoeuvres, helping to squeeze blood back out of their legs and reduce the chance of them passing out.