AEST , did they do that? Is the density variable across the sky ? Why is the G- CALM report being hidden and kept out of the public domain , one of the only ( to my knowledge ) official test flights with measuring equipment on board.
1. Yes they did
2. Of course it's variable
3. The measuring equipment on G-CALM may provide indication on concentration at some specific areas, unfortunately that's largely irrelevant
The unknown factor is What concentrations of ash starts degrading them engines?
The testflights of the airlines seem more attuned to that than the so-called scientific flight!