20180728018179A

THE PA-28-140, N624FL, DEPARTED THE 2450 FT GRASS RUNWAY 03 AT SACKMAN FIELD AIRPORT IN COLUMBIA, ILLINOIS AT 14:20 CDT, ON 28 JULY 2018 WITH A DESTINATION OF ALTON, ILLINOIS. THE AIRCRAFT MADE A SHALLOW CLIMB UNTIL CONTACTING POWER TRANSMISSION LINES BETWEEN 60 AND 70 FEET ABOVE THE GROUND 3050 FEET FROM THE DEPARTURE END OF THE RUNWAY. THE AIRCRAFT DESCENDED UNTIL CONTACTING DOWN SLOPING TERRAIN PARALLEL TO THE RIGHT SIDE OF AN ELEVATED ROADWAY 355 FEET FROM THE POWER LINE. THE AIRCRAFT CONTACTED THREE CULVERT OPENINGS THAT ANGLED FLUSH WITH THE SLOPE. IT CAME TO REST FACING 360 DEGREES AGAINST A SPEED LIMIT SIGN 442 FEET FROM THE POWER LINE.

THE WEATHER WAS VFR AT THE ST LOUIS DOWNTOWN AIRPORT, KCPS, 7.5 NM NORTHEAST 30 MINUTES BEFORE AND AFTER THE ACCIDENT AND REPORTED AS FEW CLOUDS 3,000 AND BROKEN 10,000 FEET, CALM, ALTIMETER 30.15 AND 26 DEGREES CENTIGRADE.

THE 243-HOUR PRIVATE PILOT ^PRIVACY DATA OMITTED^ IN THE RIGHT FRONT PILOT SEAT AND 50 HOUR STUDENT PILOT IN THE LEFT PILOT SEAT SUSTAINED SERIOUS INJURIES. THE STUDENT PILOT?S WIFE IN THE LEFT REAR SEAT SUSTAINED SERIOUS INJURIES AND THE OWNER?S 7-YEAR-OLD SON IN THE RIGHT REAR SEAT SUSTAINED MINOR INJURIES.

THE AIRCRAFT SUSTAINED SUBSTANTIAL DAMAGE BUT THE CABIN AREA REMAINED RELATIVELY INTACT. THE DRAINAGE CULVERTS SHEARED OFF THE NOSE AND RIGHT LANDING GEARS. THE ENGINE AND PROPELLER SHIFTED BUT REMAINED ATTACHED TO THE AIRFRAME. FLIGHT CONTROL CONTINUITY WAS ESTABLISHED TO BOTH AILERONS. THE STABILATOR AND RUDDER CONTROLS WERE JAMMED AND THE CONTROL SURFACES WOULD NOT MOVE. FIRST RESPONDERS REMOVED THE ROOF TO EXTRICATE THE LEFT REAR SEAT PASSENGER.

AN OBSERVATION OF THE POWER LINE REVEALED THE OUTER ALUMINUM WRAPS OF THE STATIC WIRE SEVERED WITH THE INNER STEEL WOUND CORE REMAINING INTACT. THE ONE AND ONE QUARTER INCH ALUMINUM POWER TRANSMISSION LINE BELOW WAS SEVERED ON A 45 DEGREE ANGLE WITH BLACK AND RED PAINT TRANSFER CORRESPONDING TO THE PROPELLER.

THREE WITNESSES OBSERVED THE AIRCRAFT IN A LEVEL FLIGHT ALTITUDE AS IT DEPARTED THE AIRPORT AT A LOWER THAN NORMAL ALTITUDE. TWO OF THESE WITNESSES STATED THE AIRCRAFT WAS WOBBLING. ONE WITNESS IN AN OPEN VEHICLE NOTED NORMAL ENGINE NOISE FROM THE AIRCRAFT.

THE WEIGHT AND BALANCE WAS NEAR THE MAXIMUM GROSS WEIGHT OF 2150 POUNDS AND CENTER OF GRAVITY WAS WITHIN LIMITS. THE INVESTIGATOR USED PASSENGER WEIGHTS PROVIDED BY LAW ENFORCEMENT AND VERIFIED BY THE PILOT TO COMPUTE THE WEIGHT AND BALANCE USING THE AIRCRAFT FLIGHT MANUAL. THE RECOVERY COMPANY REMOVED APPROXIMATELY 35 GALLONS OF 100LL FUEL FROM THE WING TANKS.

A REVIEW OF THE MAINTENANCE RECORDS AT A TACHOMETER TIME OF 6719.85 HOURS CONFIRMED THE AIRCRAFT WAS OPERATING WITH A VALID ANNUAL INSPECTION AND IN COMPLIANCE WITH ALL APPLICABLE AIRWORTHINESS DIRECTIVES. THE RECENT MAINTENANCE CONSISTED OF: LEFT MAGNETO REPLACED WITH AN OVERHAULED UNIT AND RIGHT MAGNETO REPAIRED AT 6604.5, DECEMBER 13, 2016; CYLINDERS ONE AND TWO REPLACED WITH NEW UNITS AT 6615.93, MAY 31, 2017; ANNUAL INSPECTION AND AIRWORTHINESS DIRECTIVES COMPLETED AT 6652.72, NOVEMBER 15, 2017; NEW LEFT AND RIGHT MAGNETO HARNESS AT 6686.6, JANUARY 22, 2018

AN FAA INSPECTOR WITH THE ASSISTANCE OF THE RECOVERY COMPANY EXAMINED THE ENGINE AT THE RECOVERY FACILITY ON JULY 30, 2018. THE TOP SPARKPLUG FOR CYLINDER #2 HAD AN EXCESSIVE AMOUNT OF DARK SOOT WHILE THE REMAINING TOP SPARKPLUGS HAD NORMAL OPERATING SIGNATURES. A CYLINDER DIFFERENTIAL COMPRESSION TEST PERFORMED WITH THE ENGINE AT AN OUTSIDE AIR TEMPERATURE OF 76 DEGREES FAHRENHEIT WERE CYLINDER #1 50/80, #2 19/80, #3 52/80, AND #4 50/80. THE LOWER SPARKPLUG FOR CYLINDER #2 HAD EXCESSIVE SOOT OVER 2/3 OF THE COMBUSTION AREA AND 1/3 HAD A NORMAL OPERATION SIGNATURE. A VISUAL INSPECTION OF THE OUTSIDE AND INTERIOR BORESCOPE OF CYLINDER #2 REVEALED NO CRACKS OR DAMAGE CAUSING THE LOW COMPRESSION. FUEL DRIPPED FROM THE CARBURETOR AFTER REMOVAL OF THE LOWER DRAIN PLUG AND ADDITIONAL FUEL RAN OUT WITH THROTTLE ARM MOVEMENT.