Pilot Debrief

INTERPLANE S R O SKYBOY near Miami, FL — 2011-10-29

Final reportERA12FA052
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Date
2011-10-29
Location
Miami, FL, USA
Airport
04FA
Aircraft
INTERPLANE S R O SKYBOY
Registration
N58784
Category
Airplane
Highest injury
Fatal
Fatalities
2
Phase of flight
Maneuvering

Probable cause

The pilot’s failure to maintain control of the airplane while flying at low speed, which resulted in a subsequent aerodynamic stall, spin, and impact with terrain. Contributing to the outcome of the accident was the pilot’s decision to operate the airplane with a passenger aboard before fully evaluating the airplane’s handling characteristics after vortex generators were installed.

Contributing factors

Contributing to the outcome of the accident was the pilot's decision to operate the airplane with a passenger aboard before fully evaluating the airplane's handling characteristics after vortex generators were installed.

NTSB narrative

Before the accident, the pilot had modified the airplane by installing vortex generators onto the airplane's wings. Following the installation, the pilot made an uneventful flight, and, shortly after, he departed on the accident flight. Several witnesses reported seeing the airplane, after a brief flight in the local area, flying directly over the airport at a very low speed. One witness reported that the airplane appeared to enter an aerodynamic stall and a left spin and then impacted the ground. Postaccident examination of the wreckage revealed that the left elevator trim tab upper control cable exhibited significant corrosion and had separated. A detailed examination of the cable and the separation fracture surfaces revealed the presence of significant, unabated corrosion, which had resulted in the cable losing an estimated 90 percent of its strength before ultimately failing in overload. However, it could not be determined whether the failure of this cable occurred before, or as a result of, the airplane's impact with terrain or, what effect, if any, the in-flight failure of this cable could have had on the controllability of the airplane. The wreckage examination did not reveal any other evidence of preimpact mechanical discrepancies or malfunctions that would have prevented normal operation of the engine and airframe components. No evidence was found indicating whether the pilot had intended to perform or had completed a structured flight test of the airplane's performance following the installation of the vortex generators in accordance with its operating limitations (outside of the single, 7-minute solo flight that immediately preceded the accident flight) before operating a flight with a passenger onboard.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot should have established a structured flight test plan for new modifications.

NTSB coding

Evidence available

  • Photos
  • 20 docket documents
View NTSB final reportView NTSB docket

Docket documents20

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