A few years ago, I employed an old coach driver who wanted to do some HGV driving before he retired, we had problems with some trucks steaming up due to getting in with wet or dampish clothes after loading or unloading in the bad Wx, however his truck always seemed to be "mist free", so I asked him how he managed to keep his windows clear, apparantly it was an old coach drivers trick of using an absorbent cloth, dipped in liquid soap(Fairy Liquid I use) the secret is though this has to be done when the windows are bone dry, you simply wipe over the glass surface depositing a fine coating of liquid soap, eventually it drys off, but then when things get damp and moisture laden air is about the coating of soap resiststhe water and Hey Presto, not only can you see out from the Truck , but also the coach/bus and I would think Heli, try it , but remember to apply only to dry windows.
Peter R-B
Vfr
