At the altitudes these are flying at (10km+), the air is bone dry. Unless moisture is encountered on the ascent, there is no need for conformal coating. P.S.

At the altitudes these are flying at (10km+), the air is bone dry. Unless moisture is encountered on the ascent, there is no need for conformal coating. P.S. - I've done a fair number of these flights and can speak in more detail about this hobby on request. Great fun!