Narrative:

My student is an instrument rated multi-engine pilot. On the flight we were completing an instrument proficiency check and a biennial flight review. We had departed on an IFR flight plan. We climb to 4;000 feet and were vectored to intercept the VOR/GPS- a approach outside of initial approach fix (IAF) intersection. Due to the short duration of the flight; my student briefed the approach prior to departing. We intercepted the course outside of the intersection as instructed and was cleared for the VOR/GPS a approach. After crossing the IAF intersection; we descended to 2;400 feet as prescribed by the approach chart. Upon crossing final approach fix (FAF) my student announced descending to MDA. He completed his before landing checklist and continued the descent. As we were descending; I asked tower what our missed approach instructions will be. They advised that we could not complete the missed approach IFR. We proceeded to cancel IFR and continue the approach VFR. The tower advised us to climb to the northeast upon executing the missed approach. With my student under the hood; I started looking for the airport. As I am looking for the airport; something caught me eye. I scanned the area for traffic; as I look back toward the airport. The sight picture looked like we were a little low. I look at the altimeter and it is showing 1;050 feet. I confirm the MDA is 1;220 feet and say we are below MDA. My student corrects the altitude up to MDA and executed the missed approach upon arriving at the missed approach point. Once stabilized at a safe altitude; I asked my student why he proceeded below MDA. I did have the airport in sight; but he was still under the hood. He explained he looked at the height above ground and confused it with the MDA. We had a quick discussion about the confused value and proceeded to execute another practice approach at a different airport. Once we landed and exited the aircraft; we had a detailed discussion about the approach charts. All his subsequent approaches were very good. As the instructor; I was distracted for a few moments when something caught my attention. In that time frame; the aircraft continued below MDA. Once I realized this; we immediately corrected the altitude and continued the procedure at the correct altitudes. In the future; I will focus on not being distracted at a critical moment with a student. I was trying to make sure it was not traffic; but was unable to verify that. I will also have my students state the altitude they are descending to. As a result of this; I instructed my student to round the MDA/DH to the next highest 100 and to make sure it is entered into the altitude selector on his pfd.

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Original NASA ASRS Text

Title: A C414 instructor administering an Instrument Proficiency Check and BFI became distracted during an approach with the student under the hood so he missed the student's descent below the 1;220 feet MDA.

Narrative: My student is an instrument rated multi-engine pilot. On the flight we were completing an Instrument Proficiency Check and a Biennial Flight Review. We had departed on an IFR flight plan. We climb to 4;000 feet and were vectored to intercept the VOR/GPS- A approach outside of initial approach fix (IAF) intersection. Due to the short duration of the flight; my student briefed the approach prior to departing. We intercepted the course outside of the intersection as instructed and was cleared for the VOR/GPS A approach. After crossing the IAF intersection; we descended to 2;400 feet as prescribed by the approach chart. Upon crossing final approach fix (FAF) my student announced descending to MDA. He completed his before landing checklist and continued the descent. As we were descending; I asked Tower what our missed approach instructions will be. They advised that we could not complete the missed approach IFR. We proceeded to cancel IFR and continue the approach VFR. The Tower advised us to climb to the northeast upon executing the missed approach. With my student under the hood; I started looking for the airport. As I am looking for the airport; something caught me eye. I scanned the area for traffic; as I look back toward the airport. The sight picture looked like we were a little low. I look at the altimeter and it is showing 1;050 feet. I confirm the MDA is 1;220 feet and say we are below MDA. My student corrects the altitude up to MDA and executed the missed approach upon arriving at the missed approach point. Once stabilized at a safe altitude; I asked my student why he proceeded below MDA. I did have the airport in sight; but he was still under the hood. He explained he looked at the height above ground and confused it with the MDA. We had a quick discussion about the confused value and proceeded to execute another practice approach at a different airport. Once we landed and exited the aircraft; we had a detailed discussion about the approach charts. All his subsequent approaches were very good. As the instructor; I was distracted for a few moments when something caught my attention. In that time frame; the aircraft continued below MDA. Once I realized this; we immediately corrected the altitude and continued the procedure at the correct altitudes. In the future; I will focus on not being distracted at a critical moment with a student. I was trying to make sure it was not traffic; but was unable to verify that. I will also have my students state the altitude they are descending to. As a result of this; I instructed my student to round the MDA/DH to the next highest 100 and to make sure it is entered into the altitude selector on his PFD.

Data retrieved from NASA's ASRS site 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.