# STC SA5490NM

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Dow Aero LLC, United States
- Description: Installation of World Auxiliary Power Co. (WAPCO) mid passenger doorway airstair and FWD (L1) passenger doorway airstair, AFT stowage configuration.
- Applied: July 11, 1991
- Status date: March 13, 2025
- Product: Aircraft, Large Airplane
- Certification basis: Part 25
- Data sheets: [TCDS A2NM](https://openairdocs.org/tcds/A2NM)
- Certificate PDF: https://openairdocs.org/files/sha256/20/4e/204ebd6d5cf3db0e54ead3c99365469546a99c54908b68a2d7129b5f07a4c668
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID172868597720250401154855.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA5490NM

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company 757-200 Series ([TCDS A2NM](https://openairdocs.org/tcds/A2NM))

## What the certificate says

Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record.

SA5490NM Dow Aero, LLC 6800 Camille Avenue Oklahoma City, OK 73149 Part 25 the Federal Aviation Regulations A2NM Boeing 757-200 Series The installer must determine whether this design change is compatible with previously approved modifications. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission.

07/11/1991 07/16/1997 01/05/2000 12/03/2001 12/22/1991 for Paul Nguyen Manager, Central Certification Branch Compliance & Airworthiness Division Aircraft Certification Service 3 Installation of World Auxiliary Power Company (WAPCO) mid passenger doorway airstair and FWD (L1) passenger doorway airstair, AFT stowage configuration in accordance with FAA approved WAPCO Drawing List Number 1423-5700, Revision "A", dated November 6, 1991, or later FAA approved revision.

FAA 8110-2 ( 10/24) Page 2 of __

SA5490NM 03/13/2025 3

SA5490NM 03/13/2025 Date Reissued:

04/28/2008; 12/11/2020; 03/13/2025

-END- 3 3

## Every issue (3)

- March 13, 2025: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/20/4e/204ebd6d5cf3db0e54ead3c99365469546a99c54908b68a2d7129b5f07a4c668)
- December 11, 2020: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/3b/e9/3be95541c0565bee590384944464dae4921b2abe3b3a23320f2f3b25b0cc3256)
- April 28, 2008: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/d9/07/d90779cbf063c86a71da8136168fc29fad8cc4c893bcfa896a8252368fef5d7b)

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