What was found
FLT#2061 LGA-RSW. ' DESCENDING THROUGH APPROXIMATELY 9000 AT FLIGHT IDLE A PRONOUNCED ODOR (FUMES SUSPECTED) WAS OBSERVED ON THE FLIGHT DECK BY THE CAPTAIN AND FIRST OFFICER. ODOR WAS SIMILAR TO MAGIC MARKER OR SOLVENT AND WAS MILD TO MODERATE IN INTENSITY. THE ODOR CEASED WHEN PACK 1 WAS DESELECTED. HP VALVE WAS NOTED OPEN DURING THE EVENT. NO CABIN ODOR WAS REPORTED BY INFLIGHT OR PAX; C/W INFORMATIONAL NOTICE 2017-T015 SECT B (1). A/C IS OK FOR CONTINUED SERVICE. REF 3407280/1 LG PG FOR PACK MEL.' (SUPPLEMENTAL TO FOLLOW)