Narrative:

After practicing approachs at a nearby airport, I had my student request the VOR approach to our home airport. ATC issued a vector and instructed we remain VFR. Controller asked if we could maintain VFR at a lower altitude. We replied, 'negative.' controller issued IFR clearance to home airport. With the lower altitude, we entered IMC. Controller issued approach clearance and vector to final. It seemed unusually long time between last vector and receipt of course guidance. At the FAF we started timing and began descending to MDA, while tracking the primary NAVAID. Breaking out of IMC, I noticed our position was south of the final approach course (we checked the VOR's legal tolerance for IFR before the flight), though the obs and CDI gave on course indications. Tower then instructed, 'turn right heading 020 degrees, climb and maintain 3000', contact departure on (specified frequency). We complied, and the departure controller issued a heading and altitude to set us up for another approach. Again, usually long period of time between intercept vector and course guidance. Upon breaking out of the clouds, I again noticed us south of course though the obs and CDI indicated on course. Upon entering VMC, I cancelled IFR, adjusted for a straight in, and was cleared to land. Supplemental information from acn 145959: the VOR a (hwd) approach was issued by bay TRACON. In addition to approach clearance issued by bay TRACON, the controller offered, 'caution, wake turbulence, air carrier medium large transport,' (on the oak runway 29 ILS). This traffic is intended to parallel the hwd approachs. Although both VOR's ground checked that day within 1 degree, and the #1 navigation put us at least 2MI south of course, and in dangerous proximity to the oak 29 ILS. We were issued missed approach instructions upon switching to hwd tower. After a second approach and braking out of the clouds, it was confirmed we were indeed 1-2 mi south of the field. There is no excuse for me not to tune the #2 navigation to oak 114 degree right to double-check #1 navigation after receiving the heading to intercept. Both radios and vors are being sent in for a chkup.

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Original NASA ASRS Text

Title: GA SMA ON IFR TRAINING FLT UNABLE TO TRACK OAK VOR CORRECTLY WHEN ON VOR-A APCH TO HWD.

Narrative: AFTER PRACTICING APCHS AT A NEARBY ARPT, I HAD MY STUDENT REQUEST THE VOR APCH TO OUR HOME ARPT. ATC ISSUED A VECTOR AND INSTRUCTED WE REMAIN VFR. CTLR ASKED IF WE COULD MAINTAIN VFR AT A LOWER ALT. WE REPLIED, 'NEGATIVE.' CTLR ISSUED IFR CLRNC TO HOME ARPT. WITH THE LOWER ALT, WE ENTERED IMC. CTLR ISSUED APCH CLRNC AND VECTOR TO FINAL. IT SEEMED UNUSUALLY LONG TIME BTWN LAST VECTOR AND RECEIPT OF COURSE GUIDANCE. AT THE FAF WE STARTED TIMING AND BEGAN DSNDING TO MDA, WHILE TRACKING THE PRIMARY NAVAID. BREAKING OUT OF IMC, I NOTICED OUR POS WAS S OF THE FINAL APCH COURSE (WE CHKED THE VOR'S LEGAL TOLERANCE FOR IFR BEFORE THE FLT), THOUGH THE OBS AND CDI GAVE ON COURSE INDICATIONS. TWR THEN INSTRUCTED, 'TURN RIGHT HDG 020 DEGS, CLB AND MAINTAIN 3000', CONTACT DEP ON (SPECIFIED FREQ). WE COMPLIED, AND THE DEP CTLR ISSUED A HDG AND ALT TO SET US UP FOR ANOTHER APCH. AGAIN, USUALLY LONG PERIOD OF TIME BTWN INTERCEPT VECTOR AND COURSE GUIDANCE. UPON BREAKING OUT OF THE CLOUDS, I AGAIN NOTICED US S OF COURSE THOUGH THE OBS AND CDI INDICATED ON COURSE. UPON ENTERING VMC, I CANCELLED IFR, ADJUSTED FOR A STRAIGHT IN, AND WAS CLRED TO LAND. SUPPLEMENTAL INFO FROM ACN 145959: THE VOR A (HWD) APCH WAS ISSUED BY BAY TRACON. IN ADDITION TO APCH CLRNC ISSUED BY BAY TRACON, THE CTLR OFFERED, 'CAUTION, WAKE TURB, ACR MLG,' (ON THE OAK RWY 29 ILS). THIS TFC IS INTENDED TO PARALLEL THE HWD APCHS. ALTHOUGH BOTH VOR'S GND CHKED THAT DAY WITHIN 1 DEG, AND THE #1 NAV PUT US AT LEAST 2MI S OF COURSE, AND IN DANGEROUS PROX TO THE OAK 29 ILS. WE WERE ISSUED MISSED APCH INSTRUCTIONS UPON SWITCHING TO HWD TWR. AFTER A SECOND APCH AND BRAKING OUT OF THE CLOUDS, IT WAS CONFIRMED WE WERE INDEED 1-2 MI S OF THE FIELD. THERE IS NO EXCUSE FOR ME NOT TO TUNE THE #2 NAV TO OAK 114 DEG R TO DOUBLE-CHK #1 NAV AFTER RECEIVING THE HDG TO INTERCEPT. BOTH RADIOS AND VORS ARE BEING SENT IN FOR A CHKUP.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.