Narrative:

Dhc-3 floatplane operated under FAR135 VFR/day. About mid point over water; we experienced excessively high amp charge rate with smoke from generator switch; located in electrical box behind co-pilot seat. Immediately turned off generator and noticed that electrical box was hot to the touch. Talked to the company and to a company pilot in another airplane; then turned off the battery master. Due to the west wind and sea conditions it was not possible to land the floatplane in the open water below. The wind would have made a return to our departure airport longer than a continued ahead of the first sheltered landing area. Upon arrival there; the electrical box was no longer hot to the touch and there had been no smoke since the generator was turned off; about 10 to 12 minutes. Since the electrical box is located separately from other airplane systems; and since it had contained the problem; and since there was no evidence of a further problem; I made the decision to continue flight for another 12 to 15 minutes and landed. The remainder of the flight and landing was uneventful.

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Original NASA ASRS Text

Title: DHC-3 floatplane had a generator problem and made precautionary landing.

Narrative: DHC-3 floatplane operated under FAR135 VFR/Day. About mid point over water; we experienced excessively high AMP charge rate with smoke from generator switch; located in electrical box behind co-pilot seat. Immediately turned off generator and noticed that electrical box was hot to the touch. Talked to the company and to a company pilot in another airplane; then turned off the battery master. Due to the west wind and sea conditions it was not possible to land the floatplane in the open water below. The wind would have made a return to our departure airport longer than a continued ahead of the first sheltered landing area. Upon arrival there; the electrical box was no longer hot to the touch and there had been no smoke since the generator was turned off; about 10 to 12 minutes. Since the electrical box is located separately from other airplane systems; and since it had contained the problem; and since there was no evidence of a further problem; I made the decision to continue flight for another 12 to 15 minutes and landed. The remainder of the flight and landing was uneventful.

Data retrieved from NASA's ASRS site as of April 2012 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.