The highest I have been outside an aeroplane was about 14,500, where I walked a few hundred yards uphill without feeling more than a little short of breath. The highest I've skied was from 12,700 ft at the Kleine Matterhorn in Zermatt. At that height I felt uncomfortable until I had got down to 11,500 ft which felt almost like normal.
I have read that a snooker ball would compare closely to the surface of a neutron star. That's something I would love to see - something a mile across spinning at a thousand times per second.
From a safe distance! As a confirmed coward, I'm quite happy to do it from 400 light years away
Many ordinary people hike to Everest Base Camp and stay there - at over 5300m. Everest at 8,849m has been climbed without oxygen, but that is rather more risky.
The highest ski resort I’ve stayed at was Cervinia, at 6400 ft. You certainly need to drink plenty at that height, and I felt a bit headachy at times. In Ethiopia at around 7000 ft+ I felt fine but drank prodigious amounts of water. We had 1.5 l bottles per person with lunch and usually needed more.
I remember cyclists who planned to attempt some world record (the "1 hour distance" IIRC) went to train for mônths for example in Mexico City (about 2200m asl) in order to increase the number of their red cells and have more endurance.
I used to think that until I went beyond the sight of land. I then realised that when I turned around, the horizon was still at the same level behind me. If the horizon is curved down all the way round, how come it never gets any lower?
If you were close enough to observe it, I think it would be the last thing you saw!
+1. In 1987 I went from sea-level to an ice station (DYE-3) at about 8000' ASL in an aircraft, so I didn't have time to acclimatise. The station is/was elevated above the ice surface, and you climb a long set of steps to get to the living quarters. On arrival I had to stop halfway to catch my breath; I couldn't go further until I'd rested. A few days later I could pretty much run up and down the same stairs.
The CAA rules on oxygen say "You and other members of the crew must use oxygen continuously whenever the cabin altitude exceeds 10,000 ft for more than 30 minutes or any time above 13,000 ft."
Presumably going to 13000ft did put yourself at some risk. So why did you go to that height? Why not stop at 10000 ft & not even have the issue? Is there a fuel advantage of flying in thinner air where (presumably) there is less lift for the plane's wings? Can you fly faster due to less drag?
A good question, but in my view, there was no added risk (flying, like sailing, is inherently risky). The true airspeed increases with altitude due to air density but more importantly (for light aircraft economics), the wind speed increases so on those occasions, it was seeking more beneficial tailwinds that was the reason. The engine out glide angle of the plane I fly is quite steep (1.25 miles per 1,000 feet of altitude) so 10,000 feet offers 12.5 mile range and 13k 17 nm range. The higher the better over water as it also gives you time to plan and make a mayday call.
I've been in an unpressurized aircraft at 13,000 feet - necessary to ensure ground clearance in parts of the Antarctic. And actually it was too high for me - I had to go onto oxygen as I started to feel unwell. Fortunately, I wasn't flying the plane; I'm not that kind of pilot!!
Ah, the old 'Step Climb versus Cruise Climb' perennial argument so beloved of old-school air navigators ( not many left, now! ) Much more interesting than the Which Guide to Best New Anchors, Twenty-Seventh Edition....
Best approximation we could do in modern Boeings was to get cleared a block altitude then set VS+100fpm
'Different ships, different longsplices.'Best approximation we could do in modern Boeings was to get cleared a block altitude then set VS+100fpm