Aviat A-1C-200 N43LL

Summary

On 19 February 2021 at about 00:30 local time, a Aviat A-1C-200 registered N43LL, operated by Glasair III Investors LLC, was involved in an accident near Carefree, Arizona, United States. 2 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

19 February 2021 at 00:30

Classification

Accident

Location

Carefree, Arizona, United States

Nearest airport

Sky Ranch at Carefree (18AZ)

Coordinates

33.8181, -111.8979

Aircraft

Aviat A-1C-200

Registration

N43LL

Category

Airplane

Year built

2018

Engines

1

Operator

Glasair III Investors LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Albuquerque → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR21LA135

Nobody was injured.

The substandard installation of the airplane’s autopilot system hardware, which resulted in a malfunction of the rudder control system during flight and a loss of directional control during the landing roll.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot reported that, during the approach to land, he disconnected the autopilot, and the airplane immediately yawed to the right. The pilot applied left pedal, engaged the yaw damper, and continued the approach. He subsequently disengaged the yaw damper and entered a cross-control slip to descend, and he was unable to make an effective left rudder input. The airplane touched down on the gravel runway surface and veered to the right. The airplane then crossed over to the asphalt runway surface and subsequently ground-looped. The airplane’s autopilot had been installed in the airplane 7 weeks before the accident. Postaccident examination of the airframe revealed that the autopilot hardware installation was substandard. Specifically, the guard pin, which was designed to prevent the bridle cable from traveling out of the pulley’s groove past the sheaves, was not installed to the yaw servo tray and the right pulley assembly, which allowed the yaw servo bridle cable to separate from the pulley’s phenolic sheave. Additionally, the bridle cable, which was undertensioned, became trapped between the yaw servo pulley and the attachment tray and prohibited the pilot from applying left rudder. As a result, the pilot was unable to maintain directional control during the landing roll. The guard pin is designed to prohibit the bridle cable from being able to travel out of the pulley’s groove past the sheaves.

Quoted verbatim from the NTSB record.