What was found
DURING APPROACH AFTER GEAR EXTENSION, RIGHT MAIN GEAR UNSAFE INDICATION ILLUMINATED. DURING GO-AROUND, INDICATION CEASED. AFTER GEAR RETRACTION INDICATION REMAINED EXTINGUISHED. DURING SUBSEQUENT EXTENSION, ALL INDICATIONS NORMAL. AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE CLEANED RIGHT MAIN LANDING GEAR INDICATION SWITCH, OPERATIONAL CHECK WAS NORMAL.