Since the falling experiments without oxygen had already given such good results, falling experiments were begun only at 20 km. [65,600 ft.] altitude, and, because of the limitations described above, could be carried out only to 21 km. [68,900 ft.]. In these the results obtained by Lutz and Wendt were fully corroborated in this respect, that jumps from above 21 km. [68,900 ft.] can probably be made without danger, and that ebullition of the blood does not yet take place up to 21 km. [68,900 ft.] altitude. On the other hand in a falling experiment with human beings, neither a post-hypoxemic pseudo-death nor a post-hypoxemic twilight sleep were ever observed (Lutz). In conclusion, we must make it particularly clear that, in view of the extreme experimental conditions in this whole experimental series, no fatality and no lasting injury due to oxygen lack occurred. V. Conclusions from the Results For practical rescues by parachute jump from the highest and higher altitudes the experiments yielded the following: The parachute jump without oxygen with immediate opening of the parachute is possible up to a jumping altitude of 13 km. [42,700 ft.]; the jump with oxygen equipment can be made at jumping altitudes up to 18 km. [59,100 ft.]. Advice must be given against jumping and immediate opening of the parachute since there is considerable danger of freezing and there is no need to pull the rip cord at high altitudes. However the experimental data give some indication of the chances of the parachute jumper whose parachute has become unfolded from whatever cause. The jump with a free fall and opening of the parachute at low altitudes can be made without oxygen equipment up to altitudes of 20 km. [65,600 ft.], with oxygen up to 21 km. [68,900 ft.], and probably considerably higher. In all the experiments at great height, even in experiments with oxygen breathing, unconsciousness occurred extraordinarily rapidly and was naturally preceded by loss of control before that. In one unfavorable case of a subject in the standing position during a descending experiment with oxygen, jumping from an altitude of 18 km. [59,100 ft.], unconsciousness occurred after 7 seconds. One may not count on a longer time than 10 seconds before loss of control occurs at high altitudes even with the body at rest. So within that time the airplane must be abandoned or at least one must activate the ejection seat. The technical solution of this problem must be found through a different approach. It is certain only that it will be impossible to climb out under one’s own power, that one must avoid absolutely all bodily exertion, and that the time must be kept as short as possible. Rescue is still possible from very great heights; the critical part is the abandoning of the aircraft.