Heathrow Director,Anthony GA's & others suggestions that a/c fly into the ash cloud over the UK and then inspect for any damage is not insane it is the only way to get empirical evidence of acceptable ash density levels,we need to be proactive if things do not improve,I for one would be perfectly prepared to do this research as would most other pilots (I've asked around).If we just sit on our arses wringing our hands,we can kiss goodbye to our industry.
Easily done. I would do it.
If you want to be reeeaaallly conservative, you fly a 4-engine airframe around on two engines to conduct the research, and leave two engines for standby just in case. Stabilisation alt of an empty heavy on 2 engines?? Must be quite high.
(Not that these ash concentrations are likely to be a problem - except perhaps that grey-brown band over the Thames in previous pic).