Narrative:

Departed on runway 36; and retracted the landing gear. Had previously advised the tower I intended water operations on [nearby] lake (approx 6 nm northwest of ZZZ). Flew directly to the south end of the lake to inspect landing area; and made a lh traffic pattern over the intended landing site. While on downwind I (inappropriately) extended the gear as I would have for a land landing; and confirmed gear position via mechanical indicators and electric gear position indicators. Normal approach and at touch down an immediate pitch forward due to extended landing gear. Aircraft came to rest slightly past vertical in the water. I exited the aircraft without difficulty; and as it continued to rotate to inverted; climbed aboard a float and waited for assistance.

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Original NASA ASRS Text

Title: The pilot of an amphibious aircraft reported landing on water with the landing gear extended; resulting in damage to the aircraft.

Narrative: Departed on runway 36; and retracted the landing gear. Had previously advised the tower I intended water operations on [nearby] lake (approx 6 nm NW of ZZZ). Flew directly to the South end of the lake to inspect landing area; and made a LH traffic pattern over the intended landing site. While on downwind I (inappropriately) extended the gear as I would have for a land landing; and confirmed gear position via mechanical indicators and electric gear position indicators. Normal approach and at touch down an immediate pitch forward due to extended landing gear. Aircraft came to rest slightly past vertical in the water. I exited the aircraft without difficulty; and as it continued to rotate to inverted; climbed aboard a float and waited for assistance.

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.