Matching Pairs AVIATION ABBREVIATIONSOnline version Match the abbreviation with the correct meaning. by Steven Rafael Torres Orozco 1 S/N 2 FT 3 SL 4 SRM 5 P.S.I 6 LB 7 SB 8 AD 9 P/N PART NUMBER FOOT PRESSURE SQUARE INCH SERVICE BULLETIN SERVICE LETTER SERIAL NUMBER AIRWORTHINESS DIRECTIVE STRUCTURAL REPAIR MANUAL POUND