Narrative:

Descending through approximately 17000 ft in light to moderate rain, smooth air, aircraft was suddenly struck by lightning. 3-4 mins later, I noticed a portion of left winglet was missing. Nearest airport, when emergency declared, was the destination, avp. No PIREPS for our position were reported to us, smooth air. Aircraft radar only showed light to moderate rain. WX at destination avp was 3200 ft broken, 4100 ft overcast, 10 mi visibility. A thunderstorm was reported to aircraft arriving at fqm 50-60 mi away from our position. The initial strike drew our attention to the aircraft engine status and then CRT displays and their indications. All indications were normal. We had no 'proof' we had been struck. However, upon looking out the window 4 or 5 mins later, I noticed the portion of the left winglet was missing. An emergency was declared due to the fact that our aircraft sustained damage in-flight. Crew communication: the flight attendant was notified immediately of the possibility of the lightning strike and assured all the passenger the aircraft was operating ok. A PA was made to assure the passenger (28 total). Most weren't really aware of what took place. After noticing the winglet damage, I sent the first officer back to the cabin to inspect what could be seen of the wings and other composite control surfaces. Upon his return to the flight deck, a normal approach and landing was executed. WX in the air was deteriorating and later (several hours) was quite severe. I believe we found a small, growing imbedded cell and flew near it.

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Original NASA ASRS Text

Title: FLC OF MDT HAS INFLT LIGHTNING STRIKE WHICH DAMAGES THE L WINGLET. FLT CONTINUES TO DEST 15 MINS AWAY.

Narrative: DSNDING THROUGH APPROX 17000 FT IN LIGHT TO MODERATE RAIN, SMOOTH AIR, ACFT WAS SUDDENLY STRUCK BY LIGHTNING. 3-4 MINS LATER, I NOTICED A PORTION OF L WINGLET WAS MISSING. NEAREST ARPT, WHEN EMER DECLARED, WAS THE DEST, AVP. NO PIREPS FOR OUR POS WERE RPTED TO US, SMOOTH AIR. ACFT RADAR ONLY SHOWED LIGHT TO MODERATE RAIN. WX AT DEST AVP WAS 3200 FT BROKEN, 4100 FT OVCST, 10 MI VISIBILITY. A TSTM WAS RPTED TO ACFT ARRIVING AT FQM 50-60 MI AWAY FROM OUR POS. THE INITIAL STRIKE DREW OUR ATTN TO THE ACFT ENG STATUS AND THEN CRT DISPLAYS AND THEIR INDICATIONS. ALL INDICATIONS WERE NORMAL. WE HAD NO 'PROOF' WE HAD BEEN STRUCK. HOWEVER, UPON LOOKING OUT THE WINDOW 4 OR 5 MINS LATER, I NOTICED THE PORTION OF THE L WINGLET WAS MISSING. AN EMER WAS DECLARED DUE TO THE FACT THAT OUR ACFT SUSTAINED DAMAGE INFLT. CREW COM: THE FLT ATTENDANT WAS NOTIFIED IMMEDIATELY OF THE POSSIBILITY OF THE LIGHTNING STRIKE AND ASSURED ALL THE PAX THE ACFT WAS OPERATING OK. A PA WAS MADE TO ASSURE THE PAX (28 TOTAL). MOST WEREN'T REALLY AWARE OF WHAT TOOK PLACE. AFTER NOTICING THE WINGLET DAMAGE, I SENT THE FO BACK TO THE CABIN TO INSPECT WHAT COULD BE SEEN OF THE WINGS AND OTHER COMPOSITE CTL SURFACES. UPON HIS RETURN TO THE FLT DECK, A NORMAL APCH AND LNDG WAS EXECUTED. WX IN THE AIR WAS DETERIORATING AND LATER (SEVERAL HRS) WAS QUITE SEVERE. I BELIEVE WE FOUND A SMALL, GROWING IMBEDDED CELL AND FLEW NEAR IT.

Data retrieved from NASA's ASRS site as of July 2007 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.