NDB JAA theory question
I have a few times come across questions in the Radio Nav feedback papers questioning the various factors which will affect NDB/ADF signals. I can't remember precisely how the question was worded, but the supposed answers included snow as a factor which will reduce signal strength and range.
I am trying to find something concrete to back up this answer or deny it, but without any success. My understanding and reasoning is that the radio waves at LF/MF are far too long for rain, let alone snow to have any effect at all. For radio reflection to occur the wavelength should be no more than twice the size of the object reflecting it, as with weather radar where a wave length of 2.5 to 3 cm is required.
The only way that I can see that snow might have an effect is when there is a build up on the earial itself. Could that be why?
I would be delighted if any avionics types could shed some light, so I await with thanks.