STC SA3993NM
Current · Reissued · Aircraft · Large Multi-Engine · Rev 12/11/1998 · FAA STC database
Modification by installation of engine inlet and exhaust noise attenuation treatment including incorporation of exhaust gas internal mixers and modifications to the engine thrust reversers. View PDF on drs.faa.gov ↗
The STC PDF is authoritative: installation instructions, ICA requirements and limitations.