Maybe the engines would be built with a fale safe so that they automatically level off at a certain alitutude. That'd be better than just saying "don't fly that high" cause that would just make you want to do it. Another thing they could do if you run out of gas, ejection seats. You don't die, you just lose your car. Fair enough for being stupid enough to run out of fuel in the first place.
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The lover of inquiry must follow his beloved wherever it may lead him.
-Socrates