What was found
AFTER TAKE OFF, CREW REPORTED HEAVY SMOKE IN COCKPIT. AN EMERGENCY WAS DECLARED WITH ATC AND AIRCRAFT RETURNED TO POINT OF DEPARTURE. AIRCRAFT LANDED WITHOUT ANY FURTHER INCIDENT. MAINTENANCE PERSONNEL INSPECTED AND ADJUSTED CROSSBLEED VALVE AND RAN ENGINES, NO SMOKE NOTED. AN OPERATIONAL CHECK WAS SATISFACTORY AND THE AIRCRAFT WAS RELEASED FOR SERVICE.