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Anthony Woodward
Portland, Oregon, US
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If you see a soldier shooting into the air, run for shelter first and cringe later. Falling bullets cause injuries and deaths.
A bullet shot straight up into the sky will fly upwards until its initial kinetic energy is exhausted. It will then start falling and accelerate towards the ground under the influence of gravity until it reaches its terminal velocity, which is limited by air resistance.
According to the US Centers for Disease Control and Prevention, falling bullets can hit the ground at speeds greater than 61 metres per second (m/s). Bullets travelling between 46 and 61 m/s penetrate skin. Faster than this, and they can penetrate the skull.
Celebratory gunfire can cause injuries that require emergency room treatment and death. In Puerto Rico, 19 people were injured by celebratory gunfire on New Year’s Eve 2003, and one died. In the US too, New Year’s Eve sees guns fired into the air, and deaths have occurred in the likes of Maryland, Ohio and Texas.
Chris Daniel
Glan Conwy, Conwy, UK
Celebratory gunfire is common in many countries and sadly there are hundreds of documented cases of people being killed and injured by falling bullets.
In September this year, there was a report of 17 deaths and 41 injuries in Kabul, Afghanistan, following gunfire celebrations after the Taliban claimed to have captured the Panjshir valley.
An individual’s chance of being hit by a falling bullet is small, but if hit, the likelihood of being killed is up to five times greater, at 32 per cent, than it is from a direct gunshot. This is because injury typically occurs to the head and shoulders rather than to less critical body parts.
John Crofts
Nottingham, UK
If fired vertically into the air, a bullet can reach a height of up to around 2 miles. But because of the various forces acting on a projectile that is fired in this way, the shooter is extremely unlikely to be hit by one of his own bullets as it comes back down.
Hillary Shaw
Newport. Shropshire, UK
Even in large cities, people present a small target for a bullet falling vertically. Seen from above, the head and shoulders of a typical person who is standing has an area of around 0.1 square metres. To put this in perspective, Greater London is 1569 square kilometres and its near 10 million inhabitants present a total area of about 1 square kilometre from above. So you could fire a bullet in the air in London and (even if everybody was outdoors at the same time) it would have a 0.064 per cent chance of hitting somebody.
Mike Follows
Sutton Coldfield, West Midlands, UK
The speed of returning bullets depends partly on the angle they are fired at. Bullets fired straight upwards return with lower speeds because they tend to tumble, which increases the drag they experience. Those fired at a lower angle that follow a parabolic trajectory tend to be more aerodynamically stable. They can land several kilometres away, far enough that the sound of the weapon that fired them isn’t audible, so the cause of death isn’t immediately apparent.
A projectile fired upwards will still reach the ground with a good amount of kinetic energy. This may have been exploited by William the Conqueror in the Battle of Hastings in England in 1066.
The opposing army, led by King Harold, held a defensive position on higher ground and the arrows of William’s Norman archers ricocheted harmlessly off their shield wall. Some scholars believe that, towards the end of the battle, William ordered his archers to fire their arrows high over the shield wall so that they rained down on the English army from above. Although these arrows, falling under the force of gravity, wouldn’t have been travelling as fast as those fired directly, their energy may have been sufficient to kill soldiers who weren’t expecting arrows from above.
The Bayeaux Tapestry, which depicts this battle, may possibly show Harold being struck in the eye by an arrow at a steep angle.
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