Date:	Tuesday 15 November 2022
Time:	15:00 LT
Type:	Fairchild SA227-AT Expediter
Owner/operator:	Ameriflight
Registration:	N247DH
MSN:	AT-626B
Year of manufacture:	1985
Total airframe hrs:	29256 hours
Engine model:	Garrett TPE331-11U-611G
Fatalities:	Fatalities: 0 / Occupants: 3
Other fatalities:	0
Aircraft damage:	Substantial
Category:	Accident
Location:	Pewaukee, WI -   United States of America
Phase:	Approach
Nature:	Cargo
Departure airport:	New Orleans-Lakefront Airport, LA (NEW/KNEW)
Destination airport:	Waukesha Airport, WI (UES/KUES)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
Ameriflight flight 7141, a Fairchild SA227-AT Expediter, was substantially damaged when it impacted the ground near Pewaukee, Wisconsin.
Both flight crew members received minor injuries, and the passenger was not injured.

The flight crew reported that during the climb after departure, and during the cruise portion of the flight they occasionally experienced a momentary right yaw of the airplane. They determined that even though they experienced an occasional momentary yaw that the yaw damper system was otherwise operating and not interfering with other systems, so they elected to leave the yaw damper engaged.
The airplane was on an ILS approach to runway 10 at the Waukesha County Airport (UES) when the accident occurred. After air traffic control (ATC) had cleared them for the approach the airplane intercepted the localizer and glideslope. During the approach, the flight crew noticed that the command bars on the airplane’s flight director were indicating a climbing right turn.
According to the flight crew, at that time, the autopilot was in approach mode and was still tracking the localizer and glideslope, airspeed was about 135 kts and not trending up or down significantly, and everything except the flight director looked to be normal.
The flight crew decided to disconnect the autopilot and continue the approach, and manually fly the airplane for the remainder of the flight. The crew reported that once the autopilot was disconnected, the airplane immediately rolled to the right. Both pilots got on the controls and increased engine power to attempt to regain control of the airplane. They were able to level the airplane; however, it impacted the ground in a near-wings-level attitude.
During the accident sequence the airplane contacted trees, separating the wings from the airplane and resulting in substantial damage to the wings and fuselage.

Based on the available evidence, the airplane entered an inadvertent aerodynamic stall due to exceedance of the critical angle of attack after the flight crew allowed the airspeed to decay during the instrument approach. Although an unknown anomaly in the flight director system could have resulted in the crew becoming fixated on an errant flight director indication at the expense of airspeed control, the postaccident component examination was not able to explain the errant flight director indication that the flight crew described.

Probable Cause:
The flight crew's failure to maintain adequate airspeed and their exceedance of the airplane's critical angle of attack during the instrument approach, which resulted in an aerodynamic stall. Contributing to the accident was an undetermined anomaly in the airplane flight director system which resulted in the flight crew likely becoming fixated on the anomaly at the expense of airspeed control.

14:45 UTC / 08:45 local time:
KUES 151445Z 06006KT 1/2SM -SN OVC003 M01/M01 A3025

15:45 UTC / 09:45 local time:
KUES 151545Z 06005KT 3/4SM -SN OVC005 M01/M01 A3024

NTSB CEN23LA037

photo (c) AJ Riccobono; Pewaukee, WI; 16 November 2022

Photo: FAA

Date/time	Contributor	Updates
01-Mar-2025 13:05	ASN Update Bot	Updated [Time, Operator, Other fatalities, Nature, Source, Narrative, ]
01-Mar-2025 13:21	ASN	Updated [Time, Operator, Nature, Narrative, ]
01-Mar-2025 13:23	ASN	Updated [Photo, ]