20251002014589A

Accident · Substantial damage

FAA accident report · Siai-Marchetti SM 1019 · Richland, WA · October 2, 2025

Date: October 2, 2025 · 10:50 local
Place: Richland, WA
Airport: Richland
Phase of flight: Cruise/Level Flight
Operating rules: General operating rules (Part 91)
Damage: Substantial damage
Aircraft: N3172U
NTSB investigation: NTSBWPR26LA006
Reported as: Siai-Marchetti SM 1019
Reported engine: Allison 250-B15G
People aboard: 2
Fatal injuries: 0
Other injuries: 0
Pilot’s certificate: Airline transport
Pilot’s flight hours: 10,000 total550 in this make and model16 in the last 90 days

N3172URegistered now · Siai-Marchetti SM 1019S/N 038 · Built 1976 Airframe modelSiai-Marchetti SM 1019 Engine modelAllison 250-B15GTurbo-prop

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

Pilot noticed RPM fluxuations in cruise flight and was getting worse. Decided to land the aircraft. Pilot moved condition lever forward for landing it felt like airplane was going from beta to flight idle without moving controls. During landing, felt like went into beta and airspeed dropped below stall speed (30 knots). Added power caused power increase surge. Prop went into beta and aircrat hit ground hard taking off right landing gear. Power surged again after slowing down caused aircraft to go 90 degrees to left and into gravel for a ground loop. Root cause is to speculate prop governor acted erratically. Possible malfunction internally or linkage issue. Cowling was removed and found nothing disconnected in linkage. Suspect could have been slack or low tension causing a bow in linkage not giving proper response between control lever and prop governor. SDR is intended when firm mechanical cause is discovered.

As the FAA filed it

PILOT NOTICED RPM FLUXUATIONS IN CRUISE FLIGHT AND WAS GETTING WORSE. DECIDED TO LAND THE AIRCRAFT. PILOT MOVED CONDITION LEVER FORWARD FOR LANDING IT FELT LIKE AIRPLANE WAS GOING FROM BETA TO FLIGHT IDLE WITHOUT MOVING CONTROLS. DURING LANDING, FELT LIKE WENT INTO BETA AND AIRSPEED DROPPED BELOW STALL SPEED (30 KNOTS). ADDED POWER CAUSED POWER INCREASE SURGE. PROP WENT INTO BETA AND AIRCRAT HIT GROUND HARD TAKING OFF RIGHT LANDING GEAR. POWER SURGED AGAIN AFTER SLOWING DOWN CAUSED AIRCRAFT TO GO 90 DEGREES TO LEFT AND INTO GRAVEL FOR A GROUND LOOP. ROOT CAUSE IS TO SPECULATE PROP GOVERNOR ACTED ERRATICALLY. POSSIBLE MALFUNCTION INTERNALLY OR LINKAGE ISSUE. COWLING WAS REMOVED AND FOUND NOTHING DISCONNECTED IN LINKAGE. SUSPECT COULD HAVE BEEN SLACK OR LOW TENSION CAUSING A BOW IN LINKAGE NOT GIVING PROPER RESPONSE BETWEEN CONTROL LEVER AND PROP GOVERNOR. SDR IS INTENDED WHEN FIRM MECHANICAL CAUSE IS DISCOVERED.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.

NTSB WPR26LA006Accident · No injuriesClass 3 · LimitedPreliminary reportRichland, WAOn October 2, 2025, about 1050 Pacific daylight time, a Siai-Marchetti SM 1019, N3172U, sustained substantial damage when it was involved in an accident near Richland, Washington. The pilot and passenger were not injured. The airplane was operated as a Title…Oct 2, 2025 · Substantial damage