German car firm's timetable upset designer of navigation system (8)
I believe the answer is:
mercator
'navigation system' is the definition.
The definition suggests a singular noun which matches the answer.
'german car firm's timetable upset designer of' is the wordplay.
I cannot quite see how this works, but
an anagram of 'car' is 'rca' which is present in the answer.
'of' could be 'o' and 'o' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for mercator that I've seen before include "Projector" , "Deviser of projection" , "Flemish mapmaker, giving name to a projection" , "It turns out Mo Carter was an old Flemish cartographer" , "Flemish geographer and cartographer" .)