No fatalities

Improper Aileron Cable Installation Leads to Loss of Control During Maintenance Test Flight (N3554P)

Greeley, United States of AmericaTakeoff (climb)

On February 21, 1990, a Piper PA-31-350 Navajo Chieftain (registration N3554P) operated by Beegles Aircraft Services was involved in an aviation accident near Greeley, United States of America during takeoff. No fatalities were reported. Investigators recorded the probable cause as: The improper identification of parts in the piper PA-31-350 service manual pertaining to the aileron cables. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A).

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary report: the U.S. National Transportation Safety Board (NTSB) historical archiveUpdated 2026-07-04Data APIEditorial standards

During a maintenance test flight after right wing repair, the pilot lost control shortly after liftoff. Both occupants were seriously injured. Investigation revealed reversed aileron cables due to a service manual discrepancy.

Incident Overview

A Piper PA-31-350 aircraft, registration N3554p, was on a maintenance test flight following repairs to the right wing. Shortly after liftoff, the pilot lost control of the airplane and was unable to regain control before impacting the ground. Both occupants sustained serious injuries.

Investigation Findings

Post-accident examination of the aileron control system revealed that the right wing control cables were reversed on the aileron bellcrank. This configuration caused both ailerons to move in the same direction—either up or down—when the control wheel was turned left or right. The mechanic who performed the repairs had reassembled the right wing aileron control cables in accordance with the Piper service manual. The improper connection was the result of incorrect identification of parts within the manual.

Probable Cause

The official probable cause states: "The improper identification of parts in the piper PA-31-350 service manual pertaining to the aileron cables. This discrepancy resulted in the improper installation of the aileron cables on the right aileron bellcrank by a mechanic during the reconstruction of the right wing. The improper connection resulted in a loss of aircraft control by the pilot immediately after takeoff. Also causal to the accident were the inadequate inspection of the flight control system by a second mechanic with inspection authorization, and the inadequate preflight inspection of the flight control system by the pilot prior to takeoff."

Frequently asked questions

What happened in the 21 Feb 1990 Piper PA-31-350 Navajo Chieftain accident near Greeley, United States of America?

During a maintenance test flight after right wing repair, the pilot lost control shortly after liftoff. Both occupants were seriously injured. Investigation revealed reversed aileron cables due to a service manual discrepancy.

Were there any fatalities in the 21 Feb 1990 Piper PA-31-350 Navajo Chieftain accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 21 Feb 1990 involved a Piper PA-31-350 Navajo Chieftain, registration N3554P, operated by Beegles Aircraft Services, at Greeley, United States of America.

What was the probable cause of the accident?

The improper identification of parts in the piper PA-31-350 service manual pertaining to the aileron cables. This discrepancy resulted in the improper installation of the aileron cables on the right aileron bellcrank by a mechanic during the reconstruction of the right wing. The improper connection resulted in a loss…