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