smartori
I hope you will post the link to the flight aware site, I had not heard of it before.
I would also like to correct one thing in a previous post. it seems that this plane is a C560 built in 1994 which would make it a Citation V(five) and not the ultra encore I mentioned.
both part 91 and 135 regs would require some sort of terrain warning system.
I think back to the helios air crash, could this plane have lost Pressurization in a subtle way and cause the pilots to become incapacitated and only partially awakening at lower altitude?ATC tapes will help us understand this aspect better, but that fast that low is either fooling around or being very ill in some way or another.
j