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ATL89LA121

1989-04-05 · SOUTHERN PINES, North Carolina, United States · Minor · 1 aircraft · Status: Completed

Airport SOP

Aircraft involved

Probable cause & findings

THE PILOT'S IMPROPER USE OF THE MIXTURE CONTROLS WHICH RESULTED IN ENGINE ROUGHNESS AND THE FAILURE TO PROPERLY EXECUTE THE EMERGENCY PROCEDURE FOR A ROUGH ENGINE BY PLACING THE FUEL BOOST PUMP SWITCH IN THE LOW POSITION.

Factual narrative

THE PLT REPORTED THAT DURING CRUISE FLIGHT AN ENG BEGAN RUNNING ROUGH. HE PUT THE FUEL BOOST PUMP SWITCH IN THE HIGH BOOST POSITION AND ADVANCED THE THROTTLE, MIXTURE, AND PROP LEVERS TO MAX. THIS RESULTED IN A LOSS OF PWR ON BOTH ENGS. THE ACFT TOUCHED DOWN HARD SHORT OF THE RUNWAY DURING THE FORCED LANDING AND COLLIDED WITH TREES. THE ACFT FLT MANUAL STATED THAT THE MIXTURE MUST BE ADJUSTED AT REDUCED POWER SETTINGS TO AVOID A RICH MIXTURE. THE EMERG PROCEDURES IN THE FLT MANUAL CAUTIONS THAT A ROUGH RUNNING ENG MAY BE DUE TO TOO RICH OF A MIXTURE. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12

Verbatim from NTSB's published report. Source file NTSB_1989_ATL89LA121.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.