What was found
EMERGENCY DECLARED AFTER SMOKE FROM BOTH ENGINES WAS REPORTED FROM TOWER AND FUMES WERE PRESENT IN THE COCKPIT. POST INCIDENT OPERATIONAL CHECKS AT 65%, 85% N1 AND FULL POWER PER AMM 71-00-00-866-806 REVEALED NO INTERIOR ODOR OR ENGINE SMOKE EMISSIONS AND NORMAL OPERATION PARAMETERS OBSERVED. PERFORMED GVI WITHIN ENGINE COWLING PER SPM CHAPTER 20-70-00 WITH NO DEFECTS NOTED. CONSIDERING ALL ENGINE PARAMETERS WERE NORMAL CONSULTATION WITH ROLLS ROYCE REVEALED THAT IN SERVICE VARIATIONS IN FUEL AROMATIC CONTENT COULD DRIVE SMOKE EMISSIONS.