October 25, 2004 Migration Day 16 Headwinds Turn Them Back In LaSalle County, IL. OM The migration took off, but turned back when meeting with headwinds of 19 mph. In such strong headwinds, it would have taken two hours and 47 minutes to cover the distance from this stop to the next planned stop. They'll stay another night in LaSalle County, and hope for calmer air aloft tomorrow. Distance traveled so far remains at 192.1 statute miles. How do the pilots know it would take two hours and 47 minutes? They rely on their GPS receivers. In this audio clip, Joe tells how the GPS helps the pilots, who need to keep both hands on the control bar to steer. Here's more about GPS and how it helps the pilots leading the cranes: Where on Earth? A Look at GPS Map the Migration Make your own map using the latest migration data Try This! Journaling Question Would the GPS receiver show the plane's ground speed or air speed? Why? (Hint: See our lesson on GPS.) Journey North is pleased to feature this educational adventure made possible by the Whooping Crane Eastern Partnership (WCEP). Copyright 2003-2004 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form