FLAGSTAFF, AZ, USA
N1898J
PIPER PA 28-140
A PIPER PA 28-140 COLLIDED WITH TREES AFTER A LOSS OF ENGINE POWER. THE AIRPLANE WRECKAGE WAS EXAMINED BY THE FAA. SIX OF THE EIGHT SPARK PLUGS EXHIBITED SOOTY DARK ELECTRODES. ACCORDING TO THE ENGINE MANUFACTURER, THE ELECTRODE APPEARANCE WAS INDICATIVE OF A RICH MIXTURE. EXAMINATION OF THE AIRPLANE'S FUEL PRIMER REVEALED IT WAS UNLOCKED. ACCORDING TO THE ENGINE MANUFACTURER THIS COULD RESULT IN AN OVER PRIMED OR RICH MIXTURE. THE RICH MIXTURE AND HIGH ALTITUDE COULD RESULT IN A LOSS OF ENGINE POWER.
FAILURE OF THE PILOT-IN-COMMAND TO PROPERLY LOCK THE ENGINE PRIMER CONTROL WHICH RESULTED IN AN OVER RICH FUEL TO AIR MIXTURE AND SUBSEQUENT LOSS OF ENGINE POWER.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
