Plan revealed railway track (7)
I believe the answer is:
outline
'plan' is the definition.
(outline is a kind of plan)
'revealed railway track' is the wordplay.
'revealed' becomes 'out' (I've seen this in other clues).
'railway track' becomes 'line' (I've seen this before).
'out'+'line'='OUTLINE'
(Other definitions for outline that I've seen before include "Profile" , "Possibly tracing" , "Sketchy plan" , "Framework" , "General plan; summary" .)