What was found
LOUD NOISE FROM NOSE WAS HEARD DURING GEAR RETRACTION. NOISE (THUMP) WAS FOLLOWED WITH RED GEAR UNLOCK LIGHT REMAINING ILLUMINATED. GEAR EXTENDED WITH 3 GREEN AND UNLOCK LIGHT EXTINGUISHED. JACKED ACFT AND INSPECTED NLG AND NLG WHEELWELL DUE TO RECENT NLG SERVICING, MX, AND REPEAT WRITE-UP. NO DAMAGE NOTED TO NLG STRUT OR IN NLG WHEEL WELL. CHECK AND RESERVICE NLG STRUT PRESSURES. LOWER CHAMBER PRESS 90 PSI; UPPER CHAMBER WAS 260 PSI. COMPLIED WITH COMPLETE NG STRUT SERVICING, HYD FLUID AND NITROGEN, IAW MM CH 32-20-00, TASK 32-20-00 600. DOWNJACKED ACFT STRUT EXTENSION WITHIN LIMITS IAW MM 32-00-00. SET UPPER CHAMBER PRESS TO 280 PSI. SET LOWER CHAMBER PRESS TO 40 PSI.