Narrative:

I was entering the water from a ramp at low tide in my cessna 185 amphibian. I learned, following the incident, that the tide (full moon) was the lowest of the yr. The right nosewheel touched a rock after the aircraft left the ramp. The aircraft's forward motion was stopped momentarily and momentum caused the nose to drop and the aircraft turned over on its back. I exited the aircraft following the orderly egress of 3 passenger. The aircraft (air frame) did not touch the rocks at the end of the ramp and remained afloat in deep water upside down. Within 1 hour the aircraft was 'righted' and pulled back up the ramp. The only damage was water in the cabin and the immersion of instruments and avionics. The following day the aircraft was started. It was flown on jul/xx/95 and returned to bangor, me, on a ferry permit on jul/yy/95. Callback conversation with reporter revealed the following information: the reporter was taxiing his C185 down a boat ramp into the sea in the vicinity of chevery, canada. The pilot had done this before, but the extremely low tide and the steepness of the now exposed shore created a more difficult transition for his amphibian. As the nose gear entered the water it struck a heretofore undiscovered rock and the aircraft pitched over on its back. However, not all was lost. Not only did everyone get out of the aircraft unscathed, but with assistance from a nearby boat repair yard the C185 was removed from the water and cleaned without damage and flown the next day. The same aircraft is still flying and has been checked by maintenance and no repairs were necessary.

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Original NASA ASRS Text

Title: TAXI PROC. AMPHIBIAN ENTERING THE WATER NOSES OVER.

Narrative: I WAS ENTERING THE WATER FROM A RAMP AT LOW TIDE IN MY CESSNA 185 AMPHIBIAN. I LEARNED, FOLLOWING THE INCIDENT, THAT THE TIDE (FULL MOON) WAS THE LOWEST OF THE YR. THE R NOSEWHEEL TOUCHED A ROCK AFTER THE ACFT LEFT THE RAMP. THE ACFT'S FORWARD MOTION WAS STOPPED MOMENTARILY AND MOMENTUM CAUSED THE NOSE TO DROP AND THE ACFT TURNED OVER ON ITS BACK. I EXITED THE ACFT FOLLOWING THE ORDERLY EGRESS OF 3 PAX. THE ACFT (AIR FRAME) DID NOT TOUCH THE ROCKS AT THE END OF THE RAMP AND REMAINED AFLOAT IN DEEP WATER UPSIDE DOWN. WITHIN 1 HR THE ACFT WAS 'RIGHTED' AND PULLED BACK UP THE RAMP. THE ONLY DAMAGE WAS WATER IN THE CABIN AND THE IMMERSION OF INSTS AND AVIONICS. THE FOLLOWING DAY THE ACFT WAS STARTED. IT WAS FLOWN ON JUL/XX/95 AND RETURNED TO BANGOR, ME, ON A FERRY PERMIT ON JUL/YY/95. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR WAS TAXIING HIS C185 DOWN A BOAT RAMP INTO THE SEA IN THE VICINITY OF CHEVERY, CANADA. THE PLT HAD DONE THIS BEFORE, BUT THE EXTREMELY LOW TIDE AND THE STEEPNESS OF THE NOW EXPOSED SHORE CREATED A MORE DIFFICULT TRANSITION FOR HIS AMPHIBIAN. AS THE NOSE GEAR ENTERED THE WATER IT STRUCK A HERETOFORE UNDISCOVERED ROCK AND THE ACFT PITCHED OVER ON ITS BACK. HOWEVER, NOT ALL WAS LOST. NOT ONLY DID EVERYONE GET OUT OF THE ACFT UNSCATHED, BUT WITH ASSISTANCE FROM A NEARBY BOAT REPAIR YARD THE C185 WAS REMOVED FROM THE WATER AND CLEANED WITHOUT DAMAGE AND FLOWN THE NEXT DAY. THE SAME ACFT IS STILL FLYING AND HAS BEEN CHKED BY MAINT AND NO REPAIRS WERE NECESSARY.

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.