What was found
AIRCRAFT RETURNED TO BASE, WITH PILOTS REPORTING A BURNT ELECTRICAL SMELL, AND DIMMED EHSI. INSPECTED EHSI, AND ASSOCIATED WIRING, FINDING NO SIGNS OF DAMAGE. ULTIMATELY FOUND ALTITUDE ENCODER IN LH AVI CLOSET LOOSE FROM IT'S MOUNT PLATE, AND SIGNS OF ARCING TO GROUND. ENCODER WAS SECURED, AND SYSTEM OPERATION WAS VERIFIED.