Narrative:

While being radar vectored for a night; IMC; ILS approach; ATC assigned an altitude. Pilot not flying read back 3;000. A few seconds beforehand the left-hand wing overheat annunciator illuminated and was being dealt with initially by the pilot flying. Pilot not flying reminded pilot flying to start descent to 3;000 ft. At 3;400 ft ATC advised that the assigned altitude was 4;000 ft. Pilot not flying responded 'correcting'. Quickly after [that] ATC issued a low altitude alert with the MVA of 3;400 ft. Pilot flying disconnected the autopilot to make for a quicker adjustment of aircraft pitch for the climb to 4;000 ft. Left-hand wing overheat light extinguished and a normal ILS and landing were performed. The distraction of the wing overheat combined with an ATC hearback/readback error were the causing factors.

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Original NASA ASRS Text

Title: CE525 flight crew reports an altitude deviation causing a low altitude alert from ATC. The altitude assignment was misheard and readback incorrectly at the same time a wing overheat caution light illuminated.

Narrative: While being radar vectored for a night; IMC; ILS approach; ATC assigned an altitude. Pilot not flying read back 3;000. A few seconds beforehand the Left-Hand Wing Overheat annunciator illuminated and was being dealt with initially by the pilot flying. Pilot not flying reminded pilot flying to start descent to 3;000 FT. At 3;400 FT ATC advised that the assigned altitude was 4;000 FT. Pilot not flying responded 'correcting'. Quickly after [that] ATC issued a low altitude alert with the MVA of 3;400 FT. Pilot flying disconnected the autopilot to make for a quicker adjustment of aircraft pitch for the climb to 4;000 FT. Left-Hand Wing Overheat light extinguished and a normal ILS and landing were performed. The distraction of the wing overheat combined with an ATC hearback/readback error were the causing factors.

Data retrieved from NASA's ASRS site as of July 2013 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.