20220828015429A

AUGUST 28, 2022, ABOUT 1721 CENTRAL DAYLIGHT TIME, A SEA & SKY, INC., KRUCKER CYGNET AMPHIBIOUS WEIGHT-SHIFT AIRPLANE,^PRIVACY DATA OMITTED^, WAS SUBSTANTIALLY DAMAGED WHEN IT WAS INVOLVED IN AN ACCIDENT NEAR EMILY, MINNESOTA. THE SPORT FLIGHT INSTRUCTOR, AND ONE PASSENGER, WERE FATALLY INJURED. THE PILOT’S WIFE STATED THAT HER HUSBAND INITIATED TAKEOFF FROM THE SOUTHERN-MOST PORTION OF MINNIE LAKE TO THE SOUTH. SHE WITNESSED THE TAKEOFF AND NOTED THE AIRPLANE DID NOT BECOME AIRBORNE AT THE USUAL LOCATION, RATHER IT BECAME AIRBORNE WITH ABOUT 200 FT OF WATER REMAINING. BORDERING THE SOUTHERN END OF THE LAKE WERE TREES, THE TALLEST OF WHICH WAS ESTIMATED TO BE 70 FT TALL. SHE ESTIMATED THAT THE AIRPLANE CLIMBED TO 400 FT ABOVE THE TREES THEN SHE HEARD A “BANG” SOUND THEN SILENCE AND LOST SIGHT OF THE AIRPLANE. A HOMEOWNER WHO LIVED NEAR THE ACCIDENT SITE WENT ONTO A TRAIL OF HIS PROPERTY AND LOCATED THE WRECKAGE ABOUT 2036 CDT. THE AIRPLANE CRASHED IN A DENSELY WOODED AREA CONTAINING SMALL DIAMETER TREES WITH EVIDENCE OF A STEEP DESCENT. THERE WAS NO EVIDENCE OF BIRD REMAINS FOUND AT THE WRECKAGE SITE OR AMONG THE WRECKAGE, AND THERE ALSO WAS NO PRE OR POST IMPACT FIRE. SEVERAL TREE TRUNKS WERE NOTED TO HAVE DAMAGE CONSISTENT WITH PROPELLER BLADE CONTACT CUT AT A 45 DEGREE ANGLE.EXAMINATION OF THE AIRPLANE REVEALED IT CAME TO REST UPRIGHT ON A MAGNETIC HEADING OF ABOUT 270°, LISTING ABOUT 45° TO THE RIGHT AT 46.770733° NORTH AND -94.01418° WEST. THE WING APPEARED TO BE DISPLACED TO THE RIGHT. THE MAIN LANDING GEAR WERE IN THE RETRACTED OR WATER LANDING POSITION. THE FUEL TANK WAS IMPACTED/DAMAGED ON THE FORWARD END AND WAS NOTED TO BE LEAKING FUEL. ABOUT 6.5 GALLONS OF AUTOMOTIVE FUEL WERE DRAINED FROM THE FUEL TANK. RESIDUAL FUEL WAS NOTED IN THE CLEAR FUEL LINE FROM THE SHUTOFF VALVE TO THE ENGINE-DRIVEN FUEL PUMP; NO WATER WAS PRESENT. IT WAS ESTIMATED TO BE ABOUT 1 OUNCE. THE FUEL VENT WAS CLEAR. THE FUEL SHUTOFF VALVE WAS IN THE OPEN POSITION AND WAS FREE INTO FUEL TANK. FUEL WAS ALSO NOTED IN THE CLEAR FUEL FILTER; NO WATER WAS NOTED. THE LEFT WING LEADING-EDGE SPAR WAS OVERLOAD FRACTURED ABOUT 40.5 INCHES OUTBOARD OF THE LIFT STRUT ATTACH LOCATION. THE LIFT STRUT REMAINED ATTACHED AT BOTH ENDS. THE VERTICAL CONTROL WAS BEND ABOUT 90° 14.5 INCHES FROM THE UPPER ATTACH. THE RIGHT WING LEADING-EDGE SPAR WAS OVERLOAD FRACTURED 11 FT 3 INCHES FROM THE CENTER POINT OF THE WING. THE FLYING WIRE OR CONTROL CABLE FROM THE RIGHT LOWER CONTROL BAR ATTACH POINT TO THE CENTER FORWARD ATTACH WAS FRACTURED 32 INCHES FROM THE WING LEADING EDGE AND 43 INCHES FROM THE CONTROL BAR; THE CABLE MEASURED ABOUT 5/32’S INCH IN DIAMETER . THE ROTAX 912UL ENGINE, SERIAL NUMBER 44098965 REMAINED ATTACHED TO THE STRUCTURE AT ALL 4 ATTACH POINTS BUT THE FORE/AFT LONGITUDINAL STRUCTURAL MEMBER THAT PROVIDED SUPPORT FOR THE ENGINE WAS OVERLOAD FRACTURED NEAR A WELD FOR THE 45° BRACE FOR THE VERTICAL POST; THUS, THE ENGINE WAS CANTED SLIGHTLY TO THE RIGHT. ROTATION OF THE PROPELLER SHAFT FROM THE REDUCTION GEARBOX THROUGH 360° REVEALED CRANKSHAFT, CAMSHAFT AND VALVE TRAIN CONTINUITY TO ALL CYLINDERS AND TO THE REAR OF THE ENGINE. THUMB SUCTION AND COMPRESSION WAS NOTED IN ALL CYLINDERS. THE WARP DRIVE COMPOSITE PROPELLER REMAINED ATTACHED TO THE ENGINE REVEALED ALL BLADES REMAINED SECURED IN THE HUB. ONE BLADE THAT WAS MISSING 4 INCHES OF THE TIP, THE SEPARATED SECTION OF PROPELLER BLADE WAS NOT LOCATED, BUT THE ASSOCIATED NICKEL LEADING EDGE WITH MANUFACTURED ENDS ON BOTH ENDS WAS FOUND AMONG THE MAIN WRECKAGE. THE SECOND BLADE WAS FULL SPAN BUT PARTIALLY FRACTURED 12 INCHES FROM THE OUTBOARD END OF THE HUB. THE FINAL BLADE WAS FRACTURED ABOUT 8 INCHES FROM THE OUTBOARD END OF THE PROPELLER HUB. THE SEPARATED BLADE PIECE WHICH WAS LOCATED AT THE ACCIDENT SITE AND EXHIBITED A SEMI-CIRCULAR GOUGE ON THE LEADING EDGE OF THE BLADE ABOUT 8/32 DIAMETER WITH STRIATIONS.