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Kas

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A recent news article covered a construction worker who fell 300 feet to his death. How fast was he falling? 

 
The Emrich table states that it would take about four seconds to fall 242 feet and five seconds to fall 366 feet. Given that the construction worker was probably not in a skydiver's position, he may have fallen a little faster, so four seconds is probably a pretty good guess for how long he fell. 
 
Another table in the Emrich book notes that a person would fall about 104 feet during that fourth second. 104 feet per second is about 70 miles an hour. Since the construction worker would have continued to accelerate during that last second, it is likely that he was falling at about 80 to 90 miles per hour when he hit the ground. 
 
The exact speed would depend on how much he weighed. Emrich's calculations are based on a 170 pound skydiver wearing a main parachute and a reserve. Terminal velocity for a 170-lb person is around 120 miles per hour and it would take about 12 seconds or 1,500 feet to reach it.

 

  • For a 170-pound person wearing two parachutes and using a stable spread position, Emrich calculates that the terminal velocity (i.e, the maximum speed) would be 176 feet per second, or about 120 miles per hour. (Note: In general, the more you weigh, the faster your terminal velocity will be, although your speed will be faster if you fall head down or feet first, because those positions provides the least resistance.)
     
  • Emrich notes that this 170-pound person would reach terminal velocity after about 12 seconds and would then fall nearly 10,000 feet in one minute.
     
  • According to Emrich's calculations, this 12-second fall would cover a little under 1,500 feet, which from a terminal velocity perspective means that it doesn't make much difference whether this 170-pound person fell from 2,000 or 20,000 feet. He or she would still be moving at about 120 miles per hour

 

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@Kas, you have to be really bored to start posing how fast people will die if they fall 300 feet......

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@Kas, you have to be really bored to start posing how fast people will die if they fall 300 feet......

Bored ? Far from it. For the tens of thousands of skydiving enthusiasts around the world, the speed of descent plus body position is of paramount interest. It is also of interest to many ordinary people. Not the fact that the guy fell to his death, but how long it takes to fall from a certain height.

 

The "jumpers" from the WTC on 9/11 fell further and there are those among us who are interested in time taken from exit to impact. Nothing morbid, just general curiosity.

 

If it is not your scene, then pass on, but don`t insinuate that I am bored to describe falling bodies. It is a technical subject, which obviously goes down like a lead balloon with non-technically minded people. Well, you can`t suit everybody.

 

I would add that any skydiver who is "bored" and not interested in the relationship between time and distance fallen, should have "Dig Here" printed on their helmet. 

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Morbid curiosity is not really a subject which we want to promote here on forum, especially on such sensitive subjects as 9/11.

 

I'll close this thread now.

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