# STC SA4521SW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Gulfstream Aerospace Corporation, United States
- Description: Installation of Dual Sperry magnetic heading reference systems.
- Applied: December 18, 1979
- Status date: April 1, 1999
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A21EA](https://openairdocs.org/tcds/A21EA)
- Certificate PDF: https://openairdocs.org/files/sha256/e9/a2/e9a218b8f1ca96fad2aaae3b9da6787c19e802ed4c1110eb260a5a029da80a2b
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/4D3E78D0E9C36F9486257E1F005D230F.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA4521SW

## ADs that name it (0)

None.

## Approved models (1)

- Bombardier Inc. CL-600-1A11 (CL-600) ([TCDS A21EA](https://openairdocs.org/tcds/A21EA))

## 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.

JCmtefc plates of tEraneportatton - Jfeheral <2Vfctattmt Jkimuntatratttm upplmtetttal (Kerttftcate SA4521SW Gulf stream Aerospace Corporation 7440 Aviation Place Dallas, TX 75235 aA sneetfy- Federal Aviation A21EA Canadair CL-600-1A11 Installation of Dual Sperry Magnetic Heading Reference Systems according to Drawing List T10-007 dated 10/14/81, or later FAA approved revision.

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

. December 18, 1979 October 27, 1981 <$a£>setMteed'.- April 1, 1999 _ (Signature) ) ' S. Frances Cox, Manager Special Certification Office, Southwest Region (Title) Any alteration o/ this certificate is punishable Jby a fine of not exceeding $l,000f or imprisonment not exceeding 3 years, or both.

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name oj transferee) (Address of transferee) (Number and street) (City, State, and <7P code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, Stale, and ^1P code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- April 1, 1999: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/e9/a2/e9a218b8f1ca96fad2aaae3b9da6787c19e802ed4c1110eb260a5a029da80a2b)

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