THE FORWARD CARGO DOOR OF A PA32 OPENS JUST AFTER LIFT- OFF. PLT; WITH SOME DIFFICULTY; FLIES ACFT AROUND FOR A PRECAUTIONARY LNDG TO SECURE THE DOOR. HIS SON HAD MOVED ACFT OUT OF HANGAR AND STOWED THE TOW BAR IN THAT BIN; FAILING TO LATCH IT PROPERLY.

Narrative

IMMEDIATELY AFTER LIFT-OFF; THE FORWARD CARGO HATCH (R SIDE OF COWLING AREA) FLEW OPEN -- THIS WAS AT ABOUT 250 FT MSL. I NOTIFIED TWR AND REQUESTED TO RETURN FOR LNDG TO SECURE THE HATCH. THE PIPER SARATOGA WAS ABOUT 200 LBS UNDER GROSS WT; CLBING WAS DIFFICULT AND DIRECTIONAL CTL NECESSITATED FULL R RUDDER. A NORMAL LNDG WAS MADE; I TURNED OFF AT THE FIRST INTXN; CLOSED THE HATCH AND TOOK OFF AGAIN UTILIZING THE REMAINING 3400 FT OF RWY. MY FAMILY WAS IN THE ACFT AND WE WERE HEADED TO KAUAI FOR THE WEEKEND. MY SON HAD PULLED THE ACFT OUT OF THE HANGAR AFTER MY PREFLT. HE STOWED THE TOW BAR IN THE FORWARD CARGO HATCH; I ASSUMED HE SECURED THE HATCH. WITH THE CONFUSION; LOADING EVERYONE; INCLUDING OUR DOG; I DIDN'T DOUBLE CHK. BIG MISTAKE. I USUALLY DO A SECOND WALKAROUND RIGHT BEFORE GETTING INTO THE ACFT TO MAKE SURE EVERYTHING IS BUTTONED UP BUT I DIDN'T THIS TIME AND LOOK WHAT HAPPENED. ALSO; ONCE I WAS AIRBORNE AND CONVINCED THAT THE ACFT WAS FLYING AND HAD A POSITIVE RATE OF CLB; I DECIDED TO GAR THE PATTERN AND LAND; RATHER THAN LAND STRAIGHT AHEAD WITH THE REMAINING RWY AVAILABLE. I PROBABLY HAD MORE THAN ENOUGH TO LAND. I AM GOING TO CHK THIS OUT FURTHER.