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