Karl-Peter Griesemann, 72, is believed to have succumbed to hypoxia after pressurization failed in his Cessna Citation after taking off from Jerez in Spain with his wife Juliane, 68, their daughter Lisa, 26, and 27-year-old partner named Paul. Thousands watched the Austrian-registered “ghost plane” on flight tracking sites as it headed north-east across France and Germany on Sunday afternoon, as military interceptors and air traffic controllers failed to respond to the pilot, who was bound
