What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On August 14, 2025, at approximately 1710 central daylight time, a Piper PA-18-150, privacy data omitted, was substantially damaged when it was involved in an accident near Joliet, IL. The pilot was uninjured and there were no passengers on board. The aircraft was operated under part 91 banner tow flight.
The pilot in command (PIC) reported at aproximately 1710 local time, 2-hours into a planned 3-hour flight, while crusing at an altitude of 1100 feet above ground level (AGL), the PIC heard a “loud bang,” felt a strong vibration, and the aircraft experienced a partial loss of engine power, which escalated to a total loss of engine power. The PIC attempted to return to kjot, but due to insuffecient altitude and thrust, determined a forced landing was imminent. The banner was jettisoned at 300 ft AGL over an apartment complex and the PIC executed a forced landing in a soccer field. Upon landing the aircraft impacted a chainlink fence, ground looped and came to rest on the southwest corner of the soccer field. The aircraft sustained substantial damage to the left elevator, left forward and aft wing strut, with additional damage to the left wing tip and propeller.
During the post accident investigation oil was found in the exhaust pipe and along the belly of the aircraft. During the engine teardown examination it was revealed that the #2 engine cylinder exhaust valve head was broken of the exhaust valve stem. Most of the valve stem remained inside the valve guide while the valve head was destroyed inside the cylinder.
As the FAA filed it
ON AUGUST 14, 2025, AT APPROXIMATELY 1710 CENTRAL DAYLIGHT TIME, A PIPER PA-18-150, ^PRIVACY DATA OMITTED^, WAS SUBSTANTIALLY DAMAGED WHEN IT WAS INVOLVED IN AN ACCIDENT NEAR JOLIET, IL. THE PILOT WAS UNINJURED AND THERE WERE NO PASSENGERS ON BOARD. THE AIRCRAFT WAS OPERATED UNDER PART 91 BANNER TOW FLIGHT.
THE PILOT IN COMMAND (PIC) REPORTED AT APROXIMATELY 1710 LOCAL TIME, 2-HOURS INTO A PLANNED 3-HOUR FLIGHT, WHILE CRUSING AT AN ALTITUDE OF 1100 FEET ABOVE GROUND LEVEL (AGL), THE PIC HEARD A “LOUD BANG,” FELT A STRONG VIBRATION, AND THE AIRCRAFT EXPERIENCED A PARTIAL LOSS OF ENGINE POWER, WHICH ESCALATED TO A TOTAL LOSS OF ENGINE POWER. THE PIC ATTEMPTED TO RETURN TO KJOT, BUT DUE TO INSUFFECIENT ALTITUDE AND THRUST, DETERMINED A FORCED LANDING WAS IMMINENT. THE BANNER WAS JETTISONED AT 300 FT AGL OVER AN APARTMENT COMPLEX AND THE PIC EXECUTED A FORCED LANDING IN A SOCCER FIELD. UPON LANDING THE AIRCRAFT IMPACTED A CHAINLINK FENCE, GROUND LOOPED AND CAME TO REST ON THE SOUTHWEST CORNER OF THE SOCCER FIELD. THE AIRCRAFT SUSTAINED SUBSTANTIAL DAMAGE TO THE LEFT ELEVATOR, LEFT FORWARD AND AFT WING STRUT, WITH ADDITIONAL DAMAGE TO THE LEFT WING TIP AND PROPELLER.
DURING THE POST ACCIDENT INVESTIGATION OIL WAS FOUND IN THE EXHAUST PIPE AND ALONG THE BELLY OF THE AIRCRAFT. DURING THE ENGINE TEARDOWN EXAMINATION IT WAS REVEALED THAT THE #2 ENGINE CYLINDER EXHAUST VALVE HEAD WAS BROKEN OF THE EXHAUST VALVE STEM. MOST OF THE VALVE STEM REMAINED INSIDE THE VALVE GUIDE WHILE THE VALVE HEAD WAS DESTROYED INSIDE THE CYLINDER.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.