Cray = Guess
A computer model has been devised that improves the ability to forecast whether contrails will be formed behind high altitude jet aircraft. Such a capability would be useful for, among other things, predicting whether strategic military aircraft would likely be visible by eye to enemy forces. Radar and IR stealth doesn't do much good for bombers if their presence is betrayed by contrails. The new model boasts accurately foretelling contrails (but not their duration) on 223 out of 243 aircraft in the study. That means 92% of the time one can expect contrails. Sounds great, but as "Science News" reader John Gilbert points out, "I propose the simplest model: Always predict a contrail. You'll be right 92% of the time."