The balloonist Hawthorne C. Gray established human altitude records twice in 1927. His ascent in May 1927 went to 42,470 ft (12.94 km) which is an altitude the FAA requires the use of a pressure demand mask today, doesn't it? Because at that altitude a diluter demand mask at ambient pressure would be unable to spare you from hypoxia even if breathing 100% oxygen.

In November 1927 Gray broke his own record by reaching an altitude of more than 43,000 ft where you definitely have to be in higher-than-ambient pressure, don't you? He died in this flight, but his death occured when the balloon crashed because his oxygen supply ran out during descent though still too high, rendering him unconcious.

I'm unsure what kind of oxygen supply Gray used during his flights, but it seems to me he was the first human to use oxygen under positive pressure. All subsequent higher flights (such as those of the Piccards) were either in fully pressurized gondolas/cabins or in pressure suits.


1 Answer 1


Without knowing the method of his oxygen supply I don't think the claim can be made.

He may well have been hypoxic depending on the lenth of time with whatever suplemental Oxygen he was using at altitude.

On the second attempt he almost certainly was hypoxic although technically 'alive' when he crashed. The determination that he ran out of oxygen "on the way down" is spurious. Maybe he was hypoxic at the top and he didn't start down in a sufficient time frame for his supply because of that hypoxia.

One thing we know is that every person reacts differently to the state of hypoxia. It is also a sliding scale not an either or state.

It could be likened to getting drunk without drinking provided there were some means to teleport alcohol directly into someones stomach. They would be getting more drunk but with no external reference they would not be able to determine how much imparement they had suffered. The sad thing is, alcohol uptake does that itself for drunk drivers.

On the alive statement, Alive doesn't mean coherent or even conscious. It just means the heart is pumping. That can be determined purely by physiologcal means E.g. how injuries bleed.

  • $\begingroup$ It is confirmed that his oxygen supply ran out. It is said that his courage was greater than his oxygen supply. His last journal entry from likely just below 40,000 ft stated “Sky deep blue, sun very bright, sand all gone.” But you're right not everyone reacts the same to hypoxia and perhaps he had a long enough TUC to descend in time during his May flight. Still, this doesn't answer the question what kind of oxygen supply method he used. $\endgroup$
    – Giovanni
    Oct 22, 2022 at 16:36
  • $\begingroup$ My point that it is spurious to your question. The crux is knowing what supply method was used. Survival on the first attempt doesn't mean he was using a particular method that lets people survive now, only that he survived. The fact that he died during the second excursion would to me point to the fact that he was not using sealed oxygen delivery during the first session either, but if cannot be conclusivly proven either way. $\endgroup$ Oct 22, 2022 at 16:50

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .