Ask Mr. Answer Person: "What was that really big plane that flew over Freeport?"

Terry e-mails Mr. Answer Person: "Do you or any of your readers happen to know why a large jet, looked like a 737, flew very low over Decorah (Friday) afternoon between 1:00 and 1:30?  It came from the east going west and flew over Freeport and then over the very northern part of Decorah. We saw it through the big door at the recycling plant. It looked like it was only 1,000 feet off the ground.

Mr. Answer Person says, "The good news is that Mr. Answer Person knows you weren't seeing imaginary airplanes!  But as for what kind of plane it was and why it was flying low over Freeport, I'm stumped.  OK, readers--here's your chance: Does anyone know anything about this??