By Keith Laing - 07/08/13 04:21 PM EDT
“I can you tell you they were well below 137 [knots],” Hersman said. “It wasn’t just give or take a few knots. Once we identify exactly what their low speed was, we’re going to put that information out.”
A knot is a unit of speed that is used to measure how fast airplanes are traveling. It is equal to one nautical mile per hour, almost 1,000 feet further than one mile per hour.