A B737 LANDED IN EMER CONDITIONS DUE TO NOSE GEAR UNSAFE LIGHT AND CREW UNABLE TO VERIFY NOSE GEAR POS WHEN MANUALLY EXTENDED.

Narrative

NOSE GEAR RED LIGHT CAME ON DURING FLT. TALKED TO MAINT AND PERFORMED ABNORMAL CHKLIST AFTER LOWERING GEAR HANDLE AND ONLY MAINT GEAR EXTENDED. TRIED TO LOWER NOSE GEAR MANUALLY; BUT RED LIGHT STAYED ON. VISUALLY CHKED NOSE GEAR AND ONLY SAW DAYLIGHT; BUT NO READ ALIGNMENT MARKINGS. VIEW PORT WAS HAZY DUE TO POSSIBLE OLD SODA SPILL IN COCKPIT. BRIEFED PAX AND FLT ATTENDANTS AND COMPANY BEFORE LNDG. FLAPS 40 DEGS LNDG. NOSE GEAR CAME DOWN SOMETIME DURING APCH SINCE ROLLOUT WAS NORMAL WHEN WE LOWERED THE NOSE TO THE RWY. STOPPED AND HAD MAINT PUT IN GEAR PINS AND INSPECT NOSEWHEEL; TAXIED BACK TO GATE WITHOUT ANY FURTHER PROBS. PROB WAS WITH NOSE GEAR INDICATOR CTL BOX. SINCE VIEW PORT FOR NOSE GEAR WAS HAZY IN THE COCKPIT; SUGGEST MAINT INSPECT AND CLEAN THE COCKPIT SIGHT GLASS ON A REGULAR BASIS AND HAVE FLC CHK COCKPIT VIEW PORT ALSO. CURRENT PROCS ONLY CHK THE VIEW GLASS IN THE NOSEWHEEL AREA DURING THE WALKAROUND; WHICH MAY APPEAR NORMAL. HOWEVER; SPILLS BY THE COCKPIT DOOR/GALLEY AREA COULD LEAK INTO THE VIEW PORT AND NOT BE SEEN DURING A WALKAROUND OUTSIDE.