In light of recent accidents that underscore the dangers of hypoxia, operators might want to hear the dangers for themselves. A 2008 recording of a pair of Learjet pilots who nearly lost control of their aircraft illustrates the threat that hypoxia poses. In the recording something is clearly wrong with the pilots, but they struggled to make their problem and their intentions known to a Cleveland Center controller, who figured the problem out on his own and instructed the pilots to descend.