What was found
BUF-DCA - FLT 1263 - DURING LANDING GEAR EXTENSION, ALL THREE GEAR UNSAFE LIGHTS REMAINED ILLUMINATED WITH NO GREEN LIGHTS. AFTER GEAR WAS RECYCLED, INDICATION WAS NORMAL. FLIGHT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE DUPLICATED PROBLEM WITH LANDING GEAR HANDLE SWITCH BEFORE RETRACTION CHECK. CLEANED SWITCH AT LANDING GEAR HANDLE AND PERFORMED GEAR RETRACTION CHECK SEVERAL TIMES. SYSTEM CHECKS NORMAL. (M)