A DC9 ON INITIAL CLB AT 1500 FT DIVERTED DUE TO STALL WARNING LIGHTS AND HORN ON THE CAPT'S #1 SIDE WITH NO STICK SHAKER; CAUSE UNKNOWN. FO'S #2 SIDE REMAINED NORMAL.
Synopsis
A DC9 ON INITIAL CLB AT 1500 FT DIVERTED DUE TO STALL WARNING LIGHTS AND HORN ON THE CAPT'S #1 SIDE WITH NO STICK SHAKER; CAUSE UNKNOWN. FO'S #2 SIDE REMAINED NORMAL.
Narrative
RETURNED TO CLT FOR MALFUNCTIONING STALL WARNING SYS. AFTER FLAP/SLAT RETRACTION; STALL WARNING LIGHT AND HORN (CAPT'S SIDE ONLY) CAME ON WITHOUT STICKSHAKERS. STALL INDICATION FAILURE AND WINDSHEAR INOP LIGHTS ALSO ILLUMINATED. FOLLOWED STALL INDICATION FAILURE PROC IN PLT HANDBOOK. WARNING LIGHTS (FLASHING STALL AND OVERHEAD WARNINGS) REMAINED ON WITH HORN FOR APPROX 10 MINS EVEN WITH CIRCUIT BREAKERS PULLED. ELECTED TO RETURN TO CLT. NO EMER DECLARED. FLT ATTENDANTS VERBALLY BRIEFED AND PAX ADVISED BY PA. CABIN NOT PREPARED FOR EMER LNDG SIT (NOT DEEMED NECESSARY). STALL LIGHT AND HORN EVENTUALLY WENT OUT (PROGRESSIVELY GREW WEAKER AND APPEARED TO HAVE FAILED DUE TO EXCESSIVE USE). HOWEVER; BOTH REILLUMINATED AND SOUNDED FOR APPROX 3-4 MINS DURING DSCNT TO CLT THEN CEASED PRIOR TO CONFIGN FOR LNDG AND REMAINED OUT FOR APCH; LNDG AND TAXI TO GATE. STALL COMPUTER CIRCUIT BREAKERS RESET PRIOR TO LNDG FOR STICKSHAKER CAPABILITY. AFTER LNDG; TWR ADVISED CREW THAT EMER WAS TERMINATED ALTHOUGH NONE DECLARED BY CREW. NO EMER VEHICLES NOTED ON AIRFIELD. GOOD CURRENT NOTED ON BOTH 'L AND R STALL' WHEN SELECTED ON PITOT STATIC ANTI-ICE METER. PROB POSSIBLY DUE TO ANGLE OF ATTACK VANE POS OR ELECTRICAL CIRCUITRY; BUT THESE ARE ONLY GUESSES. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT AFTER LNDG THE CREW WAS SENT TO A REPLACEMENT ACFT AND DEPARTED CLT BEFORE THE STALL WARNING WAS REPAIRED SO THE RPTR DOES NOT HAVE KNOWLEDGE OF WHAT MAINT ACTION WAS TAKEN. THE RPTR SAID THAT ALL OF THE STALL WARNING LIGHTS AND AURAL WARNING WAS ON THE CAPT'S #1 SIDE ONLY.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.