# STC SA4326SW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Sierra Industries, Inc, United States
- Description: Structural provisions for mid-lavatory service panel.
- Applied: August 29, 1979
- Status date: December 1, 1999
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 4A28](https://openairdocs.org/tcds/4A28)
- Certificate PDF: https://openairdocs.org/files/sha256/67/a4/67a431f0bd9943ff068b08ac86cb5169cb208b3e786c52146d289884c7444167
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/10D67B60639E49F885256CC2000E3B9F.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA4326SW

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company 720B Series ([TCDS 4A28](https://openairdocs.org/tcds/4A28))

## 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.

b js&tstee ©f <Anteriea ai tErsnaporfaium - Jife&mtl ^Vfrtaium (Almttmslraium (Eerttftcate SA4326SW sierra Industries, Inc., a Texas Corporation Garner Field Road Uvalde, TX 78801 4A28 Boeing 720B 4b Civil Air Structural provisions for mid-lavatory service panel according to Drawing List 43-1 dated August 28, 1979, or later FAA approved revision.

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

.-August 29, 1979 April 20, 1981 .- 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 ^IP code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, Slate, and <Y/> 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/sha256/67/a4/67a431f0bd9943ff068b08ac86cb5169cb208b3e786c52146d289884c7444167)

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