I saw some diagrams in the paper showing the vertical movements of between 45000' and 30000'. If the investigators are so sure of thevertical movement why can't they tell us where the pplane was at that moment.
They know exactly where it was when those movements were detected - above the Gulf of Thailand not long after the transponder went dead, ie at the very start of the disappearance. They know this from radar coverage. An hour or so later, the jet left the last radar area, west of Malaysia, and would only have been detectable via the equipment that had been turned off. The 'pings' are from that phase of the flight, and can only tell us the angle the plane made to the satellite that picked those signals up. Does that help?