# STC SA4156SW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Sierra Industries, Inc, United States
- Description: Installation of aft airstair.
- Applied: July 14, 1980
- Status date: December 1, 1999
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 4A26](https://openairdocs.org/tcds/4A26)
- Certificate PDF: https://openairdocs.org/files/sha256/22/0b/220b754a741ebc3ba8b3ab52383be14403c1c8254e7bf51a43f79050c44c7bcf
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5A66AA31167D4C7285256CC2000E39F2.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA4156SW

## ADs that name it (0)

None.

## Approved models (2)

- The Boeing Company 707-300 Series ([TCDS 4A26](https://openairdocs.org/tcds/4A26))
- The Boeing Company 707-400 Series ([TCDS 4A26](https://openairdocs.org/tcds/4A26))

## 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.

JBmteb J&tntee ©f .America ranspirtaitutt - Jlfcheral <&frtatum ^ministration (tterttftcate SA4156SW Sierra Industries, Inc., a Texas Corporation Garner Field Road Uvalde, TX 78801 4b Civil Air Boeing 707-300, -400 Series Installation of aft airstair in accordance with Dee Howard Drawing List No. 42 dated July 25, 1980, or later FAA approved revision.

Compatibility of this modification with other previously approved modifications must be determined by the installer.

Aatyient&eS,

•ixvOan .• July 14, 1980 .-July 25, 1980 '.• December 1, 1999 (Signature) Michele M. Owsley, Manager Airplane Certification Office, Southwest Region (Title)

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number _ to (Name of transferee) (Address of transferee) (Number and street) (City, Slate, and <7/> code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street ) ( City, State, and <7P code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- December 1, 1999: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/22/0b/220b754a741ebc3ba8b3ab52383be14403c1c8254e7bf51a43f79050c44c7bcf)

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