Narrative:

I am a flight instructor; my student is candidate for CFI-instrument. The mission was for the candidate to fly the RNAV (GPS) approach while practicing as a flight instructor. An IFR flight plan was filed and we were cleared for the GPS approach. The weather was 3;000 overcast with 10 SM visibility. The candidate intercepted the intermediate course; was cleared for the approach and initiated a descent to 2;000 MSL as required on the STAR to intercept the final approach fix. He leveled out at 2;000 MSL (we were VFR with 10 SM visibility) and initiated his landing checklist. During this time he failed to maintain an effective cross check and he descended rapidly below his intermediate segment minimum altitude of 2;000 MSL. I immediately pointed out his altitude; instructed him to climb at full power back to minimum altitude. The candidate complied and approach called with a low altitude warning. The key to prevention is continued emphasis on instrument scan; positional awareness and practice cockpit management. I have scheduled simulator time with the candidate to reinforce these techniques prior to another flight.

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Original NASA ASRS Text

Title: C172 instrument instructor experiences an altitude deviation by his CFII student during a GPS approach. ATC also takes note of the deviation.

Narrative: I am a flight instructor; my student is candidate for CFI-Instrument. The mission was for the candidate to fly the RNAV (GPS) approach while practicing as a flight instructor. An IFR flight plan was filed and we were cleared for the GPS approach. The weather was 3;000 Overcast with 10 SM visibility. The candidate intercepted the intermediate course; was cleared for the approach and initiated a descent to 2;000 MSL as required on the STAR to intercept the final approach fix. He leveled out at 2;000 MSL (we were VFR with 10 SM visibility) and initiated his Landing checklist. During this time he failed to maintain an effective cross check and he descended rapidly below his intermediate segment minimum altitude of 2;000 MSL. I immediately pointed out his altitude; instructed him to climb at full power back to minimum altitude. The candidate complied and Approach called with a low altitude warning. The key to prevention is continued emphasis on instrument scan; positional awareness and practice cockpit management. I have scheduled simulator time with the candidate to reinforce these techniques prior to another flight.

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.