What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On July 26, 2025, at 1533Z (1033 CDT), an Aerotek pitts S-2A aircraft, piloted from the rear seat with a passenger in the front, diverted after takeoff from wittman regional airport (kosh), WI, to the uncontrolled New Holstein Municipal Airport (8D1), WI. The diversion was due to the canopy becoming unlatched and sliding back to the first detent position, which, although approved for flight, increased noise levels and complicated communication with air traffic control. The flight was initially destined for austin straubel international airport (kgrb), WI. Upon landing on dry concrete runway 32 at New Holstein, the tailwheel produced an oscillating skid mark for 200 feet, followed by a leftward arc for another 200 feet, before the aircraft departed the runway and ground looped onto the grass. This resulted in the collapse of the right main and tail landing gears, causing substantial damage to the right wing and empennage. No injuries sustained to the pilot and passenger.
No alternate airport was listed in the flight plan. No maintenance corrective action was required for the canopy, as it was unlatched at takeoff.
The pilot stated he landed with a left crosswind. Metars from sheboygan county airport (ksbm), WI 18 miles southeast of New Holstein Municipal Airport (8D1), WI; before and after the accident as follows:
Ksbm 261453Z auto 00000KT 10SM clr 25/20 A2998 rmk AO2 SLP149 T02500200 55002
Ksbm 261553Z auto 00000KT 10SM OVC060 26/21 A2999 rmk AO2 SLP151 T02560206
The accident aircraft originally had a pitts Maule tailwheel (part #: SFS-1-4) with an 18-inch leaf spring (part #: 2-2250). This configuration was altered on January 6, 1978, with a scott 2000 series tailwheel installed via a field approval. On April 22, 1984, a non-field approved Maule model sfsa was installed. A modification to the tailwheel assembly was recorded on February 23, 2009 in a maintenance logpage entry, without specifying part numbers. The accident aircraft was fitted with an unapproved aviation products tailwheel assembly (part #: 6134) and a 21-inch tail spring (part #: 6171). The assembly, comprising a solid rubber tire, 6-inch double fork, and 20-degree attach block, was serviceable at the time of the accident. The pilot had owned the aircraft for less than a year, having purchased it on September 3, 2024.
As the FAA filed it
ON JULY 26, 2025, AT 1533Z (1033 CDT), AN AEROTEK PITTS S-2A AIRCRAFT, PILOTED FROM THE REAR SEAT WITH A PASSENGER IN THE FRONT, DIVERTED AFTER TAKEOFF FROM WITTMAN REGIONAL AIRPORT (KOSH), WI, TO THE UNCONTROLLED NEW HOLSTEIN MUNICIPAL AIRPORT (8D1), WI. THE DIVERSION WAS DUE TO THE CANOPY BECOMING UNLATCHED AND SLIDING BACK TO THE FIRST DETENT POSITION, WHICH, ALTHOUGH APPROVED FOR FLIGHT, INCREASED NOISE LEVELS AND COMPLICATED COMMUNICATION WITH AIR TRAFFIC CONTROL. THE FLIGHT WAS INITIALLY DESTINED FOR AUSTIN STRAUBEL INTERNATIONAL AIRPORT (KGRB), WI. UPON LANDING ON DRY CONCRETE RUNWAY 32 AT NEW HOLSTEIN, THE TAILWHEEL PRODUCED AN OSCILLATING SKID MARK FOR 200 FEET, FOLLOWED BY A LEFTWARD ARC FOR ANOTHER 200 FEET, BEFORE THE AIRCRAFT DEPARTED THE RUNWAY AND GROUND LOOPED ONTO THE GRASS. THIS RESULTED IN THE COLLAPSE OF THE RIGHT MAIN AND TAIL LANDING GEARS, CAUSING SUBSTANTIAL DAMAGE TO THE RIGHT WING AND EMPENNAGE. NO INJURIES SUSTAINED TO THE PILOT AND PASSENGER.
NO ALTERNATE AIRPORT WAS LISTED IN THE FLIGHT PLAN. NO MAINTENANCE CORRECTIVE ACTION WAS REQUIRED FOR THE CANOPY, AS IT WAS UNLATCHED AT TAKEOFF.
THE PILOT STATED HE LANDED WITH A LEFT CROSSWIND. METARS FROM SHEBOYGAN COUNTY AIRPORT (KSBM), WI 18 MILES SOUTHEAST OF NEW HOLSTEIN MUNICIPAL AIRPORT (8D1), WI; BEFORE AND AFTER THE ACCIDENT AS FOLLOWS:
KSBM 261453Z AUTO 00000KT 10SM CLR 25/20 A2998 RMK AO2 SLP149 T02500200 55002
KSBM 261553Z AUTO 00000KT 10SM OVC060 26/21 A2999 RMK AO2 SLP151 T02560206
THE ACCIDENT AIRCRAFT ORIGINALLY HAD A PITTS MAULE TAILWHEEL (PART #: SFS-1-4) WITH AN 18-INCH LEAF SPRING (PART #: 2-2250). THIS CONFIGURATION WAS ALTERED ON JANUARY 6, 1978, WITH A SCOTT 2000 SERIES TAILWHEEL INSTALLED VIA A FIELD APPROVAL. ON APRIL 22, 1984, A NON-FIELD APPROVED MAULE MODEL SFSA WAS INSTALLED. A MODIFICATION TO THE TAILWHEEL ASSEMBLY WAS RECORDED ON FEBRUARY 23, 2009 IN A MAINTENANCE LOGPAGE ENTRY, WITHOUT SPECIFYING PART NUMBERS. THE ACCIDENT AIRCRAFT WAS FITTED WITH AN UNAPPROVED AVIATION PRODUCTS TAILWHEEL ASSEMBLY (PART #: 6134) AND A 21-INCH TAIL SPRING (PART #: 6171). THE ASSEMBLY, COMPRISING A SOLID RUBBER TIRE, 6-INCH DOUBLE FORK, AND 20-DEGREE ATTACH BLOCK, WAS SERVICEABLE AT THE TIME OF THE ACCIDENT. THE PILOT HAD OWNED THE AIRCRAFT FOR LESS THAN A YEAR, HAVING PURCHASED IT ON SEPTEMBER 3, 2024.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.