# STC SA3993NM

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Federal Express Corp, United States
- Description: 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.
- Status date: December 11, 1998
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A3WE](https://openairdocs.org/tcds/A3WE)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0459DB0DB3A69E4185256CC2000C5C5C.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3993NM

## ADs that name it (1)

- [AD 2005-19-24](https://openairdocs.org/ad/2005-19-24): Forward support fitting of the number 1 and number 3 engines · Boeing 727-100 Series, 727-100C Series, 727-200 Series and 3 more. Effective Oct 27, 2005. Cited in the text

## Approved models (1)

- The Boeing Company 727-100 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))

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