My understanding is that a lot of the stuff done by the ejection seat and the parachute depend upon altitude. Somehow I also reckon a lot of thos assumptions are compeltely invalid in high ground. Is the onus on the pilot to take over manual control of all the ejection systems to avoid a nasty death? Can the ejection systems be “re-mapped” if operation over high ground is anticipated?
Your question made me curious so I did a bit of googling. I found that the ejection systems typically have different modes of operation, depending on if you are low to the ground or at high altitude, going fast or slow, etc. In the high altitude mode they will deploy a drogue chute which will keep the seat oriented and slow it somewhat until you descend to something like 15,000 feet, at which point the seat will separate from the pilot and the main chute will deploy.
If you are over a tall mountain, say 20,000 feet for example, I can see the problem you are describing. You’ll hit the ground 5,000 feet above where the automatic system would deploy the main chute, which I am assuming would be rather unpleasant.
I discovered a few things in my googling.
One is that ejection seats do apparently come with a manual override, so you’re not completely screwed if you’re up over the Himalayas.
Another thing is that ejections are rather violent, and even if you safely eject sometimes the high wind speed can rip your arms or legs off, or if you are lucky it will just break them in say half a dozen places. I’m thinking that might make it a bit difficult to operate the manual separation system.
Ejections also aren’t all that safe overall. Apparently you have about a 1 in 10 chance of dying just from the ejection. That’s better odds than riding a burning jet into the ground at 1200 mph, but still, you’d think they’d be better than that.
The last thing I learned, to my surprise, is that ejections are worse for women. On average, women weigh less than men, so they experience higher forces during ejection (force is mass times acceleration, so for the same force from the rocket motors, a lesser mass will accelerate more). Also due to their lower weight, they are more likely to oscillate when the ejection rockets fire, which makes them more prone to having their limbs broken.
Of course, assuming you survive the ejection and landing you’ll still find yourself alone in the middle of the Himalayas. Either way you’re pretty f**ed.