Narrative:

I was flying in IMC while briefing the student on the intricacies of the VOR-a approach into C35 airport with a holding pattern course reversal in lieu of the procedure turn and the orientation associated with this approach. I was not equipped with a DME but did have a yoke-mounted VFR certified GPS on the left side that was hard to see unless you faced it directly. The altimeter was partially blocked by the yoke of the left side as seen from the right flying seat side. I acknowledged the lowest altitude permitted until on a published approach segment (3500 feet versus 2700 feet) and I acknowledged I was cleared for the approach. I mistakenly thought I was close enough to the VOR to descend to 2700 feet as published on the approach procedure and was warned that 3200 feet was the minimum vectoring altitude as a just achieved 3000 feet; which was 500 feet too low. I immediately climbed back to 3200 feet and then 3500 feet. When I saw I actually was still seven miles south of the VOR. I completed the rest of the approach correctly and gave dual instruction throughout; making sure the student knew my mistake and how not to repeat something like that again.I analyze that I was over-loaded with normal approach tasks that should have cued me to stop the dual narration and just demonstrate the approach by flying it normally to the extent of a 'sterile cockpit' until I caught up with all my tasks. The airport was not a familiar airport and I had not shot this approach before. I should have accepted a radar vector when asked but I played macho and said I would do it all by myself for the sake of training the IFR applicant who only held a private pilot airplane single-engine certificate.

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Original NASA ASRS Text

Title: An Instructor Pilot demonstrating a non-precision approach to his student in a C182J descended prematurely to the course reversal altitude.

Narrative: I was flying in IMC while briefing the student on the intricacies of the VOR-A approach into C35 airport with a holding pattern course reversal in lieu of the procedure turn and the orientation associated with this approach. I was not equipped with a DME but did have a yoke-mounted VFR certified GPS on the left side that was hard to see unless you faced it directly. The altimeter was partially blocked by the yoke of the left side as seen from the right flying seat side. I acknowledged the lowest altitude permitted until on a published approach segment (3500 feet versus 2700 feet) and I acknowledged I was cleared for the approach. I mistakenly thought I was close enough to the VOR to descend to 2700 feet as published on the approach procedure and was warned that 3200 feet was the minimum vectoring altitude as a just achieved 3000 feet; which was 500 feet too low. I immediately climbed back to 3200 feet and then 3500 feet. When I saw I actually was still seven miles south of the VOR. I completed the rest of the approach correctly and gave dual instruction throughout; making sure the student knew my mistake and how not to repeat something like that again.I analyze that I was over-loaded with normal approach tasks that should have cued me to stop the dual narration and just demonstrate the approach by flying it normally to the extent of a 'sterile cockpit' until I caught up with all my tasks. The airport was not a familiar airport and I had not shot this approach before. I should have accepted a radar vector when asked but I played macho and said I would do it all by myself for the sake of training the IFR applicant who only held a private pilot airplane single-engine certificate.

Data retrieved from NASA's ASRS site as of April 2012 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.