B757 FLT CREW IS DISTRACTED BY TCAS RA FROM ACFT ON PARALLEL RWY AND FAILS TO RECALL OR DETECT THAT THE GS IS UNRELIABLE WHEN CLEARED FOR THE ILS 17L AT MCO. FLT CREW'S LATE DESCENT CATCHES THE CONTROLLER'S ATTENTION AND A SAFE LANDING ENSUES.

Narrative

THIS NARRATIVE CONTAINS 2 EVENTS THAT ARE RELATED. FIRST IS A TCAS RA EVENT AND SECOND A FALSE GLIDEPATH INTERCEPT. DURING VECTORS FOR APCH TO RWY 17L AT MCO; ACFT WAS ON A R-HAND BASE. APCH TURNED ACFT FROM 090 DEG HDG TO 120 DEG HDG AND DSNDED ACFT FROM 6000 FT TO 5000 FT. APPROX 500 FT ABOVE LEVELOFF TCAS RA COMMANDED NO FURTHER DSCNT. LEVELED AND SLIGHTLY CLBED ACFT TO AVOID CONFLICT. CONFLICT ACFT WAS AT 5000 FT AND BTWN US AND THE ARPT. CURRENT CONDITIONS WERE IMC. ADVISED ATC OF TCAS CLB AND CONTINUED WITH VECTORS WHEN CLR OF CONFLICT. RECEIVED A FINAL VECTOR TO RWY 17L AND WERE CLRED FOR THE ILS RWY 17L APCH TO INTERCEPT AT 4000 FT. ACFT WAS BEING FLOWN WITH THE AUTOPLT ON AND INTERCEPTED LOC; STARTED TO DSND TO 4000 FT FOR GLIDEPATH INTERCEPT. NEXT THE ACFT LEVELED AND ACTUALLY CLBED TO INTERCEPT GLIDEPATH. ALL COCKPIT INST SIGNALS AND DISPLAYS NORMAL. CREW DISCUSSED SITUATION AND BEGAN XCHKING ALT FOR FIXES ON THE APCH IN THE FMS. AT THAT TIME TWR ADVISED ACFT WAS HIGH AND WESTERN ARPT RWYS CAME INTO VIEW ALSO INDICATING ACFT ABOVE A NORMAL GLIDEPATH. TWR CLRED ACFT TO 1500 FT. DURING THIS DSCNT VISUAL CONDITIONS WERE ENCOUNTERED AND PAPI LIGHTS USED TO ESTABLISH NORMAL GLIDEPATH. LNDG WAS UNEVENTFUL. AFTER ACFT WAS PARKED THE CREW DISCUSSED THE SITUATION AND BOTH AGREED THAT WE WERE DISTR DURING THE APCH BY THE TCAS RA THAT HAD OCCURRED RIGHT BEFORE APCH CLRNC. ALSO; DETERMINED THAT RWY 17L GLIDEPATH WAS RPTED UNRELIABLE ON ATIS; BUT ACFT WAS CLRED FOR THE RWY 17L ILS APCH WITH NO MENTION OF THIS SITUATION. IF THE APCH CLRNC HAD OCCURRED INDEPENDENT OF THE TCAS CONFLICT; I AM CONFIDENT THAT THE CREW WOULD HAVE PICKED UP ON THE IMPROPER CLRNC AND AVOIDED ANY POTENTIAL GLIDEPATH ERRORS. THE LESSON LEARNED IS TO LEAVE ANY PROBS THAT HAPPENED IN THE PAST BEHIND YOU AND FOCUS ON THE PRESENT.