Narrative:

I departed on an IFR training flight in a piper archer on an IFR flight plan. The weather was marginal VFR; 1;500 feet overcast; calm winds and visibility greater than 10 SM. I was sitting right seat and student was in left seat. The plane has a garmin 430 waas equipped GPS with current data base. Our clearance was to maintain 3;000 feet and left turn to ZZZ1 VOR. Upon reaching 1;200 feet; I instructed student to start a left turn. We were cleared to 7;000 feet VOR 2 as a backup was not centering. We were right of course and I instructed student to turn left. The student said 'something was broke.' I immediately scanned instruments and saw we were in a steep bank; descending dive. Not knowing for sure if the instruments had failed and the greater than standard turn and excessive descent rate and I did not know what was wrong so I decided to [advise ATC]. ATC cleared us to any runway at [departure airport]. We broke out of the clouds within seconds with the airplane flying straight and level. Fire and rescue was on the way. I said it was instrumentation error and that we were fine. We reached the tie down and the firefighters asked us if we were oaky. All was fine. At this point; we tied the plane down and went home. The owner took the plane to an instrument shop the next day. The IMC was the first time for the student and may have been overwhelming. Taking control of the plane and leveling the wings was crucial to the positive outcome as well as [requesting ATC assistance] to VFR weather.

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Original NASA ASRS Text

Title: A flight instructor reported that an instrument student became disoriented due to an instrumentation problem that resulted in returning to visual conditions and a successful return to the departure airport.

Narrative: I departed on an IFR training flight in a Piper Archer on an IFR flight plan. The weather was marginal VFR; 1;500 feet overcast; calm winds and visibility greater than 10 SM. I was sitting right seat and student was in left seat. The plane has a Garmin 430 WAAS equipped GPS with current data base. Our clearance was to maintain 3;000 feet and left turn to ZZZ1 VOR. Upon reaching 1;200 feet; I instructed student to start a left turn. We were cleared to 7;000 feet VOR 2 as a backup was not centering. We were right of course and I instructed student to turn left. The student said 'something was broke.' I immediately scanned instruments and saw we were in a steep bank; descending dive. Not knowing for sure if the instruments had failed and the greater than standard turn and excessive descent rate and I did not know what was wrong so I decided to [advise ATC]. ATC cleared us to any runway at [departure airport]. We broke out of the clouds within seconds with the airplane flying straight and level. Fire and rescue was on the way. I said it was instrumentation error and that we were fine. We reached the tie down and the firefighters asked us if we were oaky. All was fine. At this point; we tied the plane down and went home. The owner took the plane to an instrument shop the next day. The IMC was the first time for the student and may have been overwhelming. Taking control of the plane and leveling the wings was crucial to the positive outcome as well as [requesting ATC assistance] to VFR weather.

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.