PA24 AND ANOTHER SIMILAR ACFT HAD NMAC MYR CLASS E AIRSPACE.

Narrative

PA24-200 CLRED TO DSND FROM 9000 FT TO 2000 FT BY MYR; SC; APCH CTL AT XA25 ON MAY/XA/01; ENRTE FROM CAE TO MYR. AT 40 DME (APPROX) FROM CRE VOR ON RADIAL FROM 270 DEGS; X WAS XING 8000 FT WHEN APCH SAID 'X; TFC ALERT! TFC ALERT! 11 O'CLOCK AND APCHING.' I WAS VMC AND LOOKING AT ALL TIMES. SCANNING COULDN'T SEE THE TFC FOR 5 OR 7 SECONDS. FINALLY TFC APPEARED FROM BLIND SPOT OF L ENG; 500 FT AHEAD XING N TO S. X STOPPED DSCNT AND TURNING N (L); EVASIVE MANEUVER; MAINTAINING SEPARATION; TOLD MYR 'MAINTAINING SEPARATION; ALREADY 500 FT ABOVE TFC.' THIS ALERT WAS GIVEN IN UNCONGESTED AIRSPACE WITH ONLY A FEW TARGETS ON THE SECTOR. X WAS IN IFR FLT PLAN CLRED TO DSND FROM 9000 FT TO 2000 FT. IF PLTS DO NOT MAKE EVASIVE ACTION; IT WOULD CULMINATE IN A COLLISION MID AIR AT 7500 FT. OTHER ACFT SIMILAR TYPE HAD FULL VIEW; APPROX MID HIGH SIDE; R-HAND WINDSHIELD. NEVER TOOK MANEUVER OF EVASION. IFR TFC ON DSCNT SHOULD NOT BE GIVEN A 10-SECOND NOTICE TO IMPACT -- SHOULD BE ADVISED IF IN RADAR ENVIRONMENT WITH AT LEAST A MINIMUM OF 5 MI. POSSIBLE CAUSE: MISATTENDED RADAR CTL SCOPE AT MYR APCH CTL.