Michel Talon wrote:

Suppose that one switches to "geometric altitude". What about people
who used to document their flights with barogaphs? Here all clubs have
barographs and lend them to the pilots when necessary. Hence the cost is
nil, which is certainly cheaper than the cheapest GPS.

Have a parallel standard. Use whichever you want. You just have to use
the same one throughout the flight (to state the obvious, I guess).

I see no problem with badge flights since they're not compared to other
flights which might use the other standard.

Graeme.