A bit more depth on the Army Airborne School 34 foot tower.
A study conducted by the Army resulted that a human would jump at 33 feet or less and believe they will/may survive a jump/ fall, and they will jump.
At 35 feet or greater, a human will jump thinking that the jump is fantasy/surreal, and they will jump.
At 34 feet, the Army determined a human will not jump, as their brain tells them they won't survive the fall, and it is not surreal/ fantasy.
That is why the Army's airborne training tower is exactly 34 feet tall. A "leg" (human) will freeze at 34 feet, and that is where the Army training requirement is to overcome the freeze from the 34 foot height.