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Flight Control Failure Accidents

4 investigationsFrom the official reportsUpdated Sep 2026

Flight control accidents involve a malfunction or misuse of the systems that move the control surfaces: a jammed elevator or stabiliser trim, a rudder that moved against the pilot's input, a disconnected cable, a loss of hydraulic power, or fly-by-wire logic that behaved differently from what the crew expected. Transport aircraft are designed so that no single failure should leave them uncontrollable, but investigations have uncovered combinations the designers did not foresee, as when an uncontained engine failure disabled all three hydraulic systems of a DC-10 in 1989 and the crew steered it with engine thrust alone.

Other reports deal with the maintenance of trim systems, with uncommanded rudder movements on the Boeing 737 in the 1990s, and with the use of the rudder in wake turbulence. The lessons for pilots concern knowing the flight control architecture of your type, recognising a control problem early, using trim cut-outs and alternate systems correctly, and handling the aircraft gently when its controllability is in doubt.

The investigations

The Qantas Airbus A330-303 registered VH-QPA.
ATSB · 2008

Qantas Flight 72

· Airbus A330-303
Faulty angle of attack spikes from one of three air data units, and a rare gap in the flight control software, made an A330 pitch down twice in cruise, injuring many unbelted occupants.
Air dataFlight controlsAutomationSurvival
The recovered vertical stabiliser of American Airlines Flight 587 being lifted by a crane beside a US Army Corps of Engineers vessel.
NTSB · 2001

American Airlines Flight 587

· Airbus A300-605R (A300B4-605R)
An A300-600's fin broke off in the climb when repeated full rudder reversals after a minor wake encounter built loads beyond the ultimate design load.
Structural failureFlight controlsLoss of controlHuman factors
The Alaska Airlines McDonnell Douglas MD-83 registered N963AS at an airport.
NTSB · 2000

Alaska Airlines Flight 261

· McDonnell Douglas MD-83
An MD-83's stabiliser trim jackscrew lost its nut threads through lack of grease, and extended check intervals let the wear go undetected until pitch control was lost.
MaintenanceFlight controlsLoss of control
The United Airlines McDonnell Douglas DC-10-10 registered N1819U, a three-engined wide-body airliner with one engine in the tail.
NTSB · 1989

United Airlines Flight 232

· McDonnell Douglas DC-10-10
A DC-10's tail engine fan disk burst in cruise and cut all three hydraulic systems; the crew steered it to Sioux City using engine thrust alone.
Engine failureFlight controlsMaintenanceCRMSurvival

The theory in the Library

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Picture credits

  1. Qantas Flight 72: Hawkeye UK · CC BY-SA 2.0 · Wikimedia Commons
  2. American Airlines Flight 587: NTSB · Public domain · Wikimedia Commons
  3. Alaska Airlines Flight 261: Frank Jäger · CC BY-SA 2.0 · Wikimedia Commons
  4. United Airlines Flight 232: Paul Seymour · CC BY-SA 4.0 · Wikimedia Commons

Crash Investigations pages summarise official investigation reports for study and exam preparation. The investigating body's report is the authoritative account and prevails wherever it differs from this page. Under ICAO Annex 13, an investigation exists to prevent accidents, not to apportion blame or liability.