Low-Altitude Maneuvering · NTSB MIA08LA121

MCKEEHAN JAMES F ACRODUSTER II SA750 — Panama City, FL

1 fatal High-time pilotLow altitude
DateJune 16, 2008
LocationPanama City, FL
AircraftMCKEEHAN JAMES F ACRODUSTER II SA750 (amateur-built)
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceManeuvering-aerobatics Loss of control in flight
Pilot age31
Pilot total time1,000 hrs · Experienced
Time in typeUnknown
Fatalities1

Probable cause

The pilot's inability to recover from an intentional aerobatic maneuver due to loss of aileron control. Contributing to the accident was the installation of an inadequate aileron secondary stop block against the main spar of both lower wings.

NTSB findings

  • Aircraft-Aircraft systems-Flight control system-Aileron control system-Incorrect service/maintenance - C
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-(general)-Attain/maintain not possible - C
  • Personnel issues-Task performance-Maintenance-Modification/alteration-Not specified - F
  • Aircraft-Aircraft systems-Flight control system-Aileron control system-Not specified - F

What happened

The passenger reported that the pilot had performed a thorough preflight inspection of the airplane and that after takeoff he performed aerobatic maneuvers over a practice area. Before the last maneuver the pilot asked the passenger if he wanted to perform what he thought was a tail slide. The flight climbed to 3,500 feet and the pilot initiated the maneuver and, after falling for a few seconds, attempted to recover. The pilot appeared to bring the nose level briefly with full power, but the airplane then started rolling to the left and right, as well as up and down, and the pilot announced that there was a malfunction. The pilot informed him to bail out of the airplane, which he did. The airplane crashed inverted in a heavily wooded area, and the passenger was unharmed. Following recovery of the airplane, inspection of the elevator and rudder flight controls by a Federal Aviation Administration inspector revealed no evidence of preimpact failure or malfunction. Inspection of the aileron flight control system revealed that wooden aileron secondary stop blocks were attached to the main spars; however, the shape was different than the stop block depicted in the builder's guide. Additionally, scrape marks associated with each aileron outer bellcrank were noted on structural support tubes inside both lower wings.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →