https://phys.org/news/2018-10-air-canada-year-worst-accident.html > "Only a few feet of separation prevented this from possibly becoming the worst aviation accident in history," said Bruce Landsberg, vice chairman of the National Transportation Safety Board while announcing the agency's report issued Friday. > "The incident airplane descended to an altitude of 100 ft (30 meters) above ground level and overflew the first airplane on the taxiway," the report said.