SMA PLT FAILS TO CLOSE HIS VFR ROUND ROBIN FLT PLAN WITH FSS.

Narrative

DID NOT CLOSE VFR FLT PLAN ON MAR/SUN/97. FLYING A T34 FLYING CLUB ACFT OUT OF EL TORO; CA. ON A LCL FLT (NZJ TO NZJ) I OPENED A LCL FLT PLAN WITH RIVERSIDE FSS AND FORGOT TO CLOSE PLAN. FACTORS WHICH AFFECTED MY THOUGHT PROCESS. 1) EL TORO TWR NORMALLY CLOSES FLT PLANS WHEN THE ACFT ARRIVES -- TWR WAS CLOSED. 2) WHEN TWR IS CLOSED; I NORMALLY CLOSE VIA RADIO WHILE AIRBORNE -- LOW VISIBILITY (APPROX 4 MI IN HAZE) DISTRACTED MY ATTN. 3) NORMALLY; NEXT SCHEDULED PLTS WAIT UNTIL ACFT IS TIED DOWN AND PAPERWORK COMPLETE IN OFFICE BEFORE PREFLTING. 'NEXT' PLTS ACCEPTED ACFT AT FUEL PUMPS. 4) DURING PAST 5 YRS; I HAVE ONLY DEPARTED EL TORO WHEN TWR WAS CLOSED; SO MY FLT PLAN CLOSURES ARE ASSOCIATED WITH CIVILIAN FIELDS. 5) FIRST TIME IN OVER 35 YRS OF FLYING I FORGOT TO CLOSE FLT PLAN! THE GOOD NEWS -- THE ACFT WAS AIRBORNE AGAIN BEFORE THE FAA WOULD HAVE BEGUN A SEARCH. THUS; THE NEW PLT WOULD BE CALLING IN TO RIVERSIDE TO OPEN HIS FLT PLAN; JUST BEFORE RIVERSIDE WOULD BE CALLING TO LOOK FOR AN OVERDUE ACFT.