Narrative:

On the day of the incident it was lifr [low instrument flight rules] conditions. Aircraft X had just departed runway xx from ZZZ; and had called me for his check on at about 023 ft. I told him 'radar contact; climb and maintain 040'. I then went on with my scan of my sector; and when I came back to aircraft X; I noticed his altitude was 015 [feet]; the pilot had descended on his own; I then asked if everything was ok and if he needed any assistance. The pilot informed me that he was having control issues and was having a hard time keeping his plane in level flight. I told him ZZZ was 4 or 5 miles south of him if he wanted to return; I then informed the supervisor of what was going on and coordinated with ZZZ about the situation. The pilot asked me what highway he was flying over; I informed him and ZZZ was 3 miles south/southwest of him. The pilot then informed me he lost all his instruments. I then continued to inform him of his position in relation to ZZZ. I also coordinated with ZZZ to issue the pilot a landing clearance if/when he got ZZZ in sight. Thankfully; the pilot was able to finally see ZZZ about 1.5 miles from the field; I issued a landing clearance and switched the pilot over to ZZZ tower and the pilot did land safely. While I did not issue the 'low altitude alert'; which was the reason this incident was brought up again for [report] purposes; I was so engrossed in trying to get the plane and pilot back to the ground safely I should have issued the 'low altitude alert'.

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Original NASA ASRS Text

Title: D10 Controller reported a twin Cessna pilot descended below clearance in low IFR weather.

Narrative: On the day of the incident it was LIFR [Low Instrument Flight Rules] conditions. Aircraft X had just departed RWY XX from ZZZ; and had called me for his check on at about 023 ft. I told him 'Radar contact; climb and maintain 040'. I then went on with my scan of my sector; and when I came back to Aircraft X; I noticed his altitude was 015 [feet]; the pilot had descended on his own; I then asked if everything was ok and if he needed any assistance. The pilot informed me that he was having control issues and was having a hard time keeping his plane in level flight. I told him ZZZ was 4 or 5 miles south of him if he wanted to return; I then informed the Supervisor of what was going on and coordinated with ZZZ about the situation. The pilot asked me what highway he was flying over; I informed him and ZZZ was 3 miles S/SW of him. The pilot then informed me he lost all his instruments. I then continued to inform him of his position in relation to ZZZ. I also coordinated with ZZZ to issue the pilot a landing clearance if/when he got ZZZ in sight. Thankfully; the pilot was able to finally see ZZZ about 1.5 miles from the field; I issued a landing clearance and switched the pilot over to ZZZ Tower and the pilot did land safely. While I did not issue the 'low altitude alert'; which was the reason this incident was brought up again for [report] purposes; I was so engrossed in trying to get the plane and pilot back to the ground safely I should have issued the 'low altitude alert'.

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.