6 fatalities

1986-05-08: Cessna 411 (N49DD) — Private United States of America — Shreveport-Downtown, United States of America

Shreveport-Downtown, United States of AmericaTakeoff (climb)

On May 8, 1986, a Cessna 411 (registration N49DD) operated by Private United States of America was involved in an aviation accident near Shreveport-Downtown, United States of America during takeoff. 6 people were killed. Investigators recorded the probable cause as: Loss of engine power (partial) due to mechanical failure/malfunction; pilot operated with known deficiencies (intentional), burned piston, improper fuel grade; loss of control due to airspeed not maintained; in flight collision with terrain; fire. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 8 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781217437Data APIEditorial standards

The pilot performed unusual engine run-ups and continued takeoff despite engine popping and black smoke. Loss of airspeed occurred during climb, the aircraft rolled inverted and struck terrain. Gross weight exceeded by 205 pounds; right engine showed evidence of gasoline/jet fuel mixture. All six occupants were killed.

Accident Sequence

The pilot conducted an unusually long engine run-up before taxiing onto the runway and performed another run-up before departure, indicating awareness of a problem. During ground run, the engines were popping and emitting black smoke. Despite these anomalies, the takeoff was continued. After liftoff, the popping and smoke persisted. A noticeable loss of airspeed occurred during the climbout. The aircraft entered a third roll (into the bad engine) and became inverted before colliding with terrain. A fire ensued.

Aircraft Information

The aircraft's allowable gross weight was exceeded by at least 205 pounds at takeoff, but the center of gravity remained within specified limits. Internal examination of the right engine revealed evidence that it had operated on a mixture of gasoline and jet fuel.

Occupants

All six occupants were killed.

Probable Cause

According to official findings, the accident involved multiple occurrences:

  • Occurrence #1: Loss of engine power (partial) due to mechanical failure/malfunction during takeoff-initial climb. Findings: operation with known deficiencies in equipment (intentional by pilot in command), burned piston, improper fuel grade.
  • Occurrence #2: Loss of control in flight during takeoff-initial climb. Finding: airspeed not maintained by pilot in command.
  • Occurrence #3: In flight collision with terrain/water during uncontrolled descent.
  • Occurrence #4: Fire.