On 27 March 1977, KLM B747-200 commenced and continued take off without clearance in poor visibility and collided with a Pan American AW Boeing 747-100 which was taxiing on the runway in accordance with its ATC clearance at Los Rodeos airport, Tenerife. All 248 people on board KLM flight died during the accident. Pan American flight carried 396 persons on board “ 61 of them survived the crash, receiving non-fatal injuries.