Ophir to the Rescue!

July 15, 2007
For those still puzzling about what actually causes contrails and why they are in the sky for such a long time, the Smithsonian's Air & Space Magazine (July/August 2007) provides an explanation.  As a part of this article, author Mariana Gosnell describes how contrails can give away stealth bomber positions.  Writing about the B-2, she quotes an Air Force meteorologist who said "They spent all this money to develop a billion-dollar bomber that's invisible to radar, but you can see its contrail with your naked eye."

Though several solutions were tried, Gosnell writes that "in the end, Ophir, an optical sensor manufacturer in Littleton, Colorado, saved the day.  Its Pilot Alert System uses lidar (light detection and ranging) to differentiate contrails from clouds and tell the pilot to change his altitude when his aircraft is "conning."