Narrative:

I was assigned to the sic position on this passenger flight to acy, nj. The flight was routine until we began the approach procedure for the VOR runway 4 at acy. The captain and I had briefed the approach procedure to include the required altitudes and the missed approach as per our SOP's. The pilot and copilot VOR receivers were tuned and idented to the frequency of 108.6, acy with the HSI course set to 048 degrees inbound. About 14 mi from the airport, the approach controller said that he noticed our equipment status was /G and did we want to be cleared for the GPS approach to runway 4 instead of the VOR approach for runway 4? I told him to stand by and began to find the GPS 4 procedure to see if there might be some advantage to using that approach. The advantage was 40 ft in altitude and closer alignment to the runway threshold. Given the ceiling and visibility at acy, changing the approach did not seem to be necessary. I replied to the controller that we would stay with the VOR approach to runway 4. The controller said, 'cleared for the VOR 4 approach.' I acknowledged the clearance and shortly thereafter, I made the callout that the VOR needle was alive. At 10 DME, the VOR needles were showing 1/4 DOT to the right, so I told the controller that we were established on the approach and were descending to 1700 ft. The controller replied that he showed us 2 mi southwest of the inbound course. At this point, I began to question the accuracy of our equipment. I asked the captain if we should load the GPS approach in the FMS and ask for that procedure. The captain said that might be a better approach, so I began looking for the GPS procedure for runway 4. The controller said he still showed us to be left of course and told me to contact the tower. Upon finding the GPS approach, I told the captain that I did not have the time to load and brief the GPS approach and we were better served at this point to stay with the VOR approach and he agreed. After we decided against changing the approach procedure, I began the before landing checklist. The approach flap setting was called for and I began calling out our altitude in our descent to the airport. During these distrs, I left the approach procedure to notify the cabin and did not reference the DME. When the gear came down, I thought we were 1 mi outside of the FAF as per SOP's and training. So when I finished with the distraction of looking for the GPS approach and the checklist, I was not surprised to see that we were descending through 1450 ft. We had ground contact at 880 ft and I reported to the tower that we had ground contact. The tower reported back that we were still 1 mi outside of meady, which is the FAF, and our altitude should be 1700 ft MSL. I am a strong user of proper procedures and checklists and I am astounded that I am a party to this error. During this case, CFIT was very likely, but fortunately did not occur. At 99.9% of airports in the world, this would have been an accident investigation and the question would be -- how did this happen? Any time an approach is filled with distrs, communication between the crew must increase. The error chain started with the concern about the difference in our position between the controller and our VOR equipment. This captain and I had not been crewed together for over a yr. We had an absence of SOP's including the failure to communicate every altitude change during an approach and why that change was being made. The distrs generated by not trusting our equipment initiated these events. We operate several aircraft with totally different equipment and configns.

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Original NASA ASRS Text

Title: H25A CREW DSNDED BELOW THE MDA DURING DSCNT FROM 1700 FT TO 1450 FT BEFORE THE FAF, ON THE VOR RWY 4 APCH AT ACY.

Narrative: I WAS ASSIGNED TO THE SIC POS ON THIS PAX FLT TO ACY, NJ. THE FLT WAS ROUTINE UNTIL WE BEGAN THE APCH PROC FOR THE VOR RWY 4 AT ACY. THE CAPT AND I HAD BRIEFED THE APCH PROC TO INCLUDE THE REQUIRED ALTS AND THE MISSED APCH AS PER OUR SOP'S. THE PLT AND COPLT VOR RECEIVERS WERE TUNED AND IDENTED TO THE FREQ OF 108.6, ACY WITH THE HSI COURSE SET TO 048 DEGS INBOUND. ABOUT 14 MI FROM THE ARPT, THE APCH CTLR SAID THAT HE NOTICED OUR EQUIP STATUS WAS /G AND DID WE WANT TO BE CLRED FOR THE GPS APCH TO RWY 4 INSTEAD OF THE VOR APCH FOR RWY 4? I TOLD HIM TO STAND BY AND BEGAN TO FIND THE GPS 4 PROC TO SEE IF THERE MIGHT BE SOME ADVANTAGE TO USING THAT APCH. THE ADVANTAGE WAS 40 FT IN ALT AND CLOSER ALIGNMENT TO THE RWY THRESHOLD. GIVEN THE CEILING AND VISIBILITY AT ACY, CHANGING THE APCH DID NOT SEEM TO BE NECESSARY. I REPLIED TO THE CTLR THAT WE WOULD STAY WITH THE VOR APCH TO RWY 4. THE CTLR SAID, 'CLRED FOR THE VOR 4 APCH.' I ACKNOWLEDGED THE CLRNC AND SHORTLY THEREAFTER, I MADE THE CALLOUT THAT THE VOR NEEDLE WAS ALIVE. AT 10 DME, THE VOR NEEDLES WERE SHOWING 1/4 DOT TO THE R, SO I TOLD THE CTLR THAT WE WERE ESTABLISHED ON THE APCH AND WERE DSNDING TO 1700 FT. THE CTLR REPLIED THAT HE SHOWED US 2 MI SW OF THE INBOUND COURSE. AT THIS POINT, I BEGAN TO QUESTION THE ACCURACY OF OUR EQUIP. I ASKED THE CAPT IF WE SHOULD LOAD THE GPS APCH IN THE FMS AND ASK FOR THAT PROC. THE CAPT SAID THAT MIGHT BE A BETTER APCH, SO I BEGAN LOOKING FOR THE GPS PROC FOR RWY 4. THE CTLR SAID HE STILL SHOWED US TO BE L OF COURSE AND TOLD ME TO CONTACT THE TWR. UPON FINDING THE GPS APCH, I TOLD THE CAPT THAT I DID NOT HAVE THE TIME TO LOAD AND BRIEF THE GPS APCH AND WE WERE BETTER SERVED AT THIS POINT TO STAY WITH THE VOR APCH AND HE AGREED. AFTER WE DECIDED AGAINST CHANGING THE APCH PROC, I BEGAN THE BEFORE LNDG CHKLIST. THE APCH FLAP SETTING WAS CALLED FOR AND I BEGAN CALLING OUT OUR ALT IN OUR DSCNT TO THE ARPT. DURING THESE DISTRS, I LEFT THE APCH PROC TO NOTIFY THE CABIN AND DID NOT REF THE DME. WHEN THE GEAR CAME DOWN, I THOUGHT WE WERE 1 MI OUTSIDE OF THE FAF AS PER SOP'S AND TRAINING. SO WHEN I FINISHED WITH THE DISTR OF LOOKING FOR THE GPS APCH AND THE CHKLIST, I WAS NOT SURPRISED TO SEE THAT WE WERE DSNDING THROUGH 1450 FT. WE HAD GND CONTACT AT 880 FT AND I RPTED TO THE TWR THAT WE HAD GND CONTACT. THE TWR RPTED BACK THAT WE WERE STILL 1 MI OUTSIDE OF MEADY, WHICH IS THE FAF, AND OUR ALT SHOULD BE 1700 FT MSL. I AM A STRONG USER OF PROPER PROCS AND CHKLISTS AND I AM ASTOUNDED THAT I AM A PARTY TO THIS ERROR. DURING THIS CASE, CFIT WAS VERY LIKELY, BUT FORTUNATELY DID NOT OCCUR. AT 99.9% OF ARPTS IN THE WORLD, THIS WOULD HAVE BEEN AN ACCIDENT INVESTIGATION AND THE QUESTION WOULD BE -- HOW DID THIS HAPPEN? ANY TIME AN APCH IS FILLED WITH DISTRS, COM BTWN THE CREW MUST INCREASE. THE ERROR CHAIN STARTED WITH THE CONCERN ABOUT THE DIFFERENCE IN OUR POS BTWN THE CTLR AND OUR VOR EQUIP. THIS CAPT AND I HAD NOT BEEN CREWED TOGETHER FOR OVER A YR. WE HAD AN ABSENCE OF SOP'S INCLUDING THE FAILURE TO COMMUNICATE EVERY ALT CHANGE DURING AN APCH AND WHY THAT CHANGE WAS BEING MADE. THE DISTRS GENERATED BY NOT TRUSTING OUR EQUIP INITIATED THESE EVENTS. WE OPERATE SEVERAL ACFT WITH TOTALLY DIFFERENT EQUIP AND CONFIGNS.

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.