The FAA's B4UFly App shows that I live in a no-fly zone within a five-mile radius of BWI; about 4.5 miles. This measurement is incorrect. Using the FAA's own published coordinates for BWI from AirNav: KBWI - Baltimore/Washington International Thurgood Marshall Airport and my own precision measurements of the geographic coordinates of my house, compiled over a number of years with various GPS devices for purposes of astronomical observing, WolframAlpha.com and Google Earth Pro agree that I am 6.8 statute miles (5.9 nm) from BWI. Using my own conservative measurements of the distance from the nearest point on BWI's perimeter to my home, WolframAlpha.com and Google Earth Pro agree that I am 6.6 statute miles (5.7 nm) from BWI. I'm going with my measurements.