As I said - I'm troubled by DB's assertion that it's OK to use a Rad Alt triggered warning that DH has been achieved when the terrain beneath may be anything other than on a level with runway threshold. I was troubled by his assertion that the terrain on short finals will be so close to runway threshold level that it makes no difference.
I can't see how this can be when we are talking about a tolerance of just 50 feet when commencing a GA.
There seems to be one school of thought that says "Rad Alts and their associated bugs and lights and whistles" are a reasonable substitute for the BarAlt. Please tell me it's not so.
G.
