In addition to my old reliable B40, I have a newly old B50. As I'm cruising
along the B50's audio will switch to slow yodel and two blue LED's will
light up indicating the need to slow down "a lot". It's usually not clear
to me why I should slow down but I've learned to trust it. After I enter
the zoom I usually feel a kick in the pants as I enter a strong thermal. It
seems to know a thermal is coming well before I do.

Mike, HOW DOES IT DO THAT?

Bill Daniels