C182 PILOT REPORTS MAKING GEAR UP LANDING AFTER LANDING GEAR WARNING HORN FAILS TO SOUND WHEN THROTTLE IS RETARDED DURING THE APPROACH.

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I RECENTLY MADE A PART 91 VFR PLEASURE FLT; IN MY PERSONAL ACFT; TO AN UNCTLED ARPT. AS I APCHED THE FIELD; AWOS WAS RPTING WINDS AT 18 KTS GUSTING TO 31 KTS; AND I HAD BEEN EXPERIENCING ENOUGH TURB THAT THE RIDE WAS NOT PLEASANT. ON 1 OCCASION DURING THE FLT; ABOUT 10 MINS FROM LNDG; THE AUTOPLT AUTOMATICALLY DISENGAGED VIA THE G-SWITCH ACCELERATION SENSOR. ALTHOUGH I DID NOT LOSE CTL OF THE ACFT DURING THIS EVENT; MAINTAINING ACFT CTL WAS A PRIMARY FOCUS DURING MY APCH TO LNDG. THIS ACFT IS EQUIPPED WITH A LNDG GEAR WARNING SYS TO HELP PREVENT AN INADVERTENT GEAR-UP LNDG. RETARDING THE THROTTLE FROM CRUISE SETTING NORMALLY PRODUCES A LOUD; INTERMITTENT TONE THROUGH THE ACFT SPEAKERS. 1 WK PRIOR TO THE INCIDENT FLT; I MADE A LCL FLT TO PRACTICE FLT PROCS AND VERIFY ACFT SYS OPS. DURING THIS PRACTICE FLT; THE LNDG GEAR WARNING SYS PERFORMED AS INTENDED DURING EACH OF SEVERAL LNDGS; SOUNDING LOUDLY AS THE THROTTLE WAS RETARDED. ON APCH DURING THE INCIDENT FLT; AS I RETARDED THE THROTTLE; THE GEAR WARNING SYS DID NOT SOUND AND I DID NOT NOTICE THE FAILURE OF THIS IMPORTANT WARNING SYS. INSTEAD; I CONTINUED SLOWING THE PLANE; ADDING FLAPS; AND MINDING ACFT CTL RIGHT DOWN TO A GEAR-UP LNDG. MY ATTN TO ACFT CTL APPARENTLY ALLOWED FOR A (RELATIVELY) SOFT IMPACT; AND THE DAMAGE TO THE ACFT WAS CONFINED TO THE PROP AND ACFT SKIN. IN A TYPICAL APCH; AS I LOWER THE GEAR; I CHK FOR A GREEN INDICATOR LIGHT AND VISUALLY VERIFY GEAR DOWN ONLY AFTER THE WARNING HORN IS SILENT AND THE MECHANICAL SOUND AND MOTION OF THE GEAR EXTENSION MECHANISM STOPS. (I WOULDN'T TRUST AN ATTEMPTED VERIFICATION BEFORE THEN.) IN THIS CASE; THE FIRST DID NOT OCCUR; AND NEITHER DID THE SECOND. AFTER CLRING THE PLANE FROM THE RWY; AN A&P LOWERED THE GEAR (IT FUNCTIONED NORMALLY); BUT DISCOVERED A BROKEN SOLDER CONNECTION ON THE LNDG GEAR WARNING SYS (IT DID NOT FUNCTION). WOULD I HAVE LOWERED THE GEAR IF THE GEAR WARNING SYS HAD BEEN SCREAMING IN MY EARS AS USUAL? I'D LIKE TO THINK I WOULD; BUT THE INCIDENT CERTAINLY WOULD NOT HAVE HAPPENED IF I HAD INDEPENDENTLY VERIFIED GEAR EXTENSION AS I APCHED LNDG. A NUMBER OF IF-ONLY SCENARIOS COULD HAVE SAVED ME FROM THIS INCIDENT: IN AN IFR APCH; I LOWER THE GEAR AT A PREDETERMINED POINT IN THE APCH. SAME WITH A STANDARD PATTERN APCH; BUT THIS WAS A STRAIGHT-IN APCH. I'LL REVISE OR RESTRICT MY STRAIGHT-IN APCHS. EVEN WITH THE RETRACTABLE GEAR; THIS IS A RELATIVELY SIMPLE AIRPLANE TO LAND. DOES IT JUSTIFY READING THROUGH A WRITTEN PRE-LNDG CHKLIST? MY ANSWER TODAY WOULD BE YES; BUT AT LEAST 1 AUTH HAS SAID THAT USING A WRITTEN OR MNEMONIC CHKLIST SHOULD BE TAUGHT BUT ANY TYPE OF CHKLIST CAN BE INTERRUPTED BY DISTRS. HOWEVER; EVEN THAT IS TAUGHT AND PRACTICED BY INSTRUCTORS. WILL I EVER MAKE ANOTHER LNDG WITHOUT THINKING ABOUT THIS ONE? NO; BUT THAT'S ONE VERY EXPENSIVE LESSON. FOR ME; IT WILL BE MORE WRITTEN CHKLISTS; A MORE RELIABLE MNEMONIC PROC FOR GEAR DOWN VERIFICATION; MORE PRACTICE WITH DISTRS; AND MORE VIGILANCE.