Mechanical & Engine Failure · NTSB ERA15FA109

PIPER PA-23 — Lakeland, FL

2 fatal High-time pilot
DateJanuary 22, 2015
LocationLakeland, FL
AircraftPIPER PA-23
Purpose of flightInstructional
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceUncontrolled descent Part(s) separation from AC
Pilot age61
Pilot total time6,609 hrs · High time
Time in typeUnknown
Fatalities2

Probable cause

An in-flight loss of control for reasons that could not be determined during postaccident investigation; the loss of control likely occurred during a simulated loss of power in the right engine during an instructional flight.

NTSB findings

  • Not determined-Not determined-(general)-(general)-Unknown/Not determined - C
  • Personnel issues-Task performance-Use of equip/info-Aircraft control-Student/instructed pilot - C
  • Personnel issues-Task performance-Use of equip/info-Aircraft control-Instructor/check pilot - C
  • Aircraft-Aircraft systems-Flight control system-Rudder control system-Capability exceeded

What happened

The flight was the seventh lesson for the multiengine student, which likely included a simulated engine failure of the right engine usually performed over or near the destination airport. After takeoff, the flight proceeded north; radar returns were consistent with airwork. The airplane then turned and began flying toward the destination airport at 3,600 ft mean sea level and 105 mph.

A witness heard a "pop" sound, and another witness heard an unusual engine sound; these might be consistent with a quick reduction in power on one engine, and, based on radar data, the airplane began to slow about that time, consistent with reduced power from one engine. The airplane then began a right turn, pitched nose down, descended into a building, and was nearly consumed by a postcrash fire. Although the final descent was captured by a security video, the low-resolution image precluded a determination of the state of the airplane at that time.

No structure associated with the aft portion of the fuselage was identified in the wreckage. Examination of sections of the fractured structure revealed no evidence of preimpact failure or malfunction. Examination of the fractured left rudder cable revealed extensive postaccident heat damage to the fracture surface that precluded determination of the fracture mode. Examination of the engines and propellers revealed no evidence of preimpact failures or malfunctions; neither propeller was in the feathered position.

The rudder with attached trim tab and a flight bag separated from the airplane during the descent came to rest outside the impact area. The separated rudder exhibited evidence of overtravel in both directions that is consistent with loss of cable tension; the reason for the loss of cable tension could not be determined. It also could not be determined how the flight bag became separated from the wreckage.

Discrepancies previously noted by Federal Aviation Administration personnel during a ramp inspection of the accident airplane had been repaired before the accident flight. Further, the pilot who flew the accident airplane the day before reported no discrepancies during that flight.

Although the toxicological finding in specimens of the pilot-rated student were positive for ethanol, it is likely that it was the result of postmortem production.

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 →