PLT OF AN ATX PIPER PA28R FAILED TO MAINTAIN ASSIGNED VECTORING ALT DURING VECTORS FOR AN APCH DUE TO PARTIAL VMC AND IMC CONDITIONS.

Narrative

WHILE RETURNING FROM BLI; ATC ASKED IF I WANTED VISUAL APCH. I STATED THAT I COULDN'T HAVE VISUAL FROM THE AREA I WAS AT (IMC BELOW) SO RECEIVED RADAR VECTORS E OF THE FIELD FOR THE RWY 31 BACK COURSE APCH. WHEN I GOT ABEAM THE ARPT AREA I COULD SEE SEATAC ARPT AND WAS TRYING TO LOCATE BFI SO I COULD ADVISE ATC AND MAYBE GET A VISUAL OR CANCEL IFR. IT WAS GOOD VMC AND I WAS DIPPING THE WING TO ATTEMPT TO SEE ARPT. I LOOKED BACK AT INSTS AND SAW I'D DSNDED TO 3500 FT MSL. I THOUGHT TO MYSELF I NEED TO GET BACK UP OR CANCEL IFR AND GO VFR. AT THAT TIME ATC CALLED AND SAID THEY NOTICED I WAS DSNDING AND ASKED INTENTIONS. I SAID I CAN GO BACK UP OR CANCEL THAT I HAD ARPT. HE SAID RETURN TO 4000 FT MSL. THE APCH WAS MADE AND NO CONFLICTS WERE ENCOUNTERED. HUMAN CONSIDERATIONS: THERE WILL BE ANOTHER RPT FROM THIS SAME DAY. I TOLD MYSELF THINGS WERE NOT GOING WELL THE FIRST THING IN THE MORNING AND IT JUST COMPOUNDED. THE COMPANY BOSS TOLD ME THE NIGHT BEFORE TO SHOW UP EARLY TO FERRY ANOTHER PLT TO HIS DEST BECAUSE HIS ACFT WAS OTS. I WAS TO GO WITH HIM TO PORT ANGELES; WA; GET BACK TO BFI ASAP TO DO MY REGULAR RUN. I SHOWED UP AT XA00; OTHER PLT ARRIVED AT XB00. MY PLANE HAD BEEN TAKEN BY ANOTHER EMPLOYEE BECAUSE HIS PLANE HAD BEEN HIT BY A CARGO CART. MY HEADSET AND APCH CHARTS; ETC; WERE IN MY PLANE AND THEY HAD TAKEN THEM; SO I DECIDED TO MAKE COPIES OF THE BFI CHARTS SO I COULD RETURN WHEN I GOT TO CLM. I COULD BUY NEW CHARTS WHEN I RETURNED TO BFI TO GO OUT ON MY REGULAR RTE. I FELT FRUSTRATED THAT THE PLTS HAD TO MOVE MY BELONGINGS TO FLY MY PLANE WITH NO CONSIDERATION THAT I MIGHT NEED THOSE THINGS. THE PLT I WAS FERRYING WOULD RATHER STAND AROUND AND VISIT WITH OTHER PLTS BECAUSE IT MIGHT BE THE CONTACT HE NEEDS TO MOVE ON TO A BIGGER AND BETTER JOB. I WAS PUTTING PRESSURE ON MYSELF BECAUSE THE BOSS HAD STRESSED IT AND SO WAS THE FREIGHT COMPANY WE WERE FLYING FOR. I LET THE 'HURRY UP' AFFECT ME WHEN IN MY MIND I KNEW TO WATCH OUT FOR THOSE TYPES OF PRESSURES.