NOTAMs
Regarding airbubba’s NOTAM, with such a complicated NOTAM what is the chance of the wrong safe or not safe areas being given to the pilot? Consider the possible data chain between the volcano and the pilot. Presumably it is something like:-
• Ash eruption density and wind speeds measured by Met Offices
• Put data in a computer model
• Model generates a map of ash concentrations
• CAA(?) by hand (presumably) add a 60 mile margin for error, approximate this boundary into straight lines and hand transfer these lines to the extensive list of coordinates on the NOTAM
• Transmit NOTAM
• ATC/airlines, etc. transfer coordinates from NOTAM to a new map by hand.
• ATC/flight planners, etc. use the new map to tell pilots where they can /can’t go.
Update it all every 6 hours.
Note the ATSIN says that original Met Office maps carries no official status so pilots can not use them to judge safe areas.
Major areas where the process could fall down is:-
• Human error in transferring data at each step
• Forget to add the 60 miles
• Failure to use the latest data e.g. copying over old data
• Failure to adapt to the ever shifting CAA, etc. policy advice
• Met Office computer modelling error
• Met Office measurement error
• Corruption of NOTAM message in transmission (unlikely)
I’d say it’s quite a high risk that the area is wrong but am prepared to be told I have got the process wrong or that there is more automation (less human input) than I think.
Is the NOTAM sytem fit for purpose for communicating this information? Would not direct electronic transfer of the original Met Office map be safer?