# STC SA5021SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: E-Systems Inc, United States
- Description: Replacement of KW7 secure comm with a KG-84 installation
- Applied: January 6, 1988
- Status date: February 27, 1990
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 4A21](https://openairdocs.org/tcds/4A21), [TCDS 4A26](https://openairdocs.org/tcds/4A26)
- Certificate PDF: https://openairdocs.org/files/sha256/28/0b/280bd8ffb20b6b9454d79e60987a53918eda9ecee3c1254324aa1702a2490a2f
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5D7A1912D752098485256CC200122613.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA5021SW-D

## ADs that name it (0)

None.

## Approved models (3)

- The Boeing Company 707-100B Long Body ([TCDS 4A21](https://openairdocs.org/tcds/4A21))
- The Boeing Company 707-100B Short Body ([TCDS 4A21](https://openairdocs.org/tcds/4A21))
- The Boeing Company 707-300B Series ([TCDS 4A26](https://openairdocs.org/tcds/4A26))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

Band Sata f Acric Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA50225N-0 This certificate issued to: E-SYstems INC. and USAF Greenville Division OC-ALC/MMS P.O. Box 1056 Tinker AFB, Okla. 73145 Greenville, Texas 75401 Certifies that the change in the type design for the following product with the limitations and conditions thorefor as specified hereon meets the airworthiness requiremonts of Port Ab of the CIVII AiX Hogulations.

Original Product TypeContificate Number: 4A21 and 4A26 Make: Boeing Model: 707-153B and 707-3533 Description of Type Design Change: RepLacement oF KNI Secure Conn with a KG-84 installation according to Sealed Drawing List SDL 7451-1, Rev. F dated 9 February 1990 or later DAS approved revision.

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

3 Date of Issuance: 5 Feb 1988 Delcamcaded: 28 JU1 1989 FEDERAL AVIATION My direction of the datinistation зин (Signature) OMIT VISTRATIO DAS Staff Coordinator, DAS45W D. T. Greene Jr.

47.

**FAR FORM 8110-2 (10-68)**

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and Z1P code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, State, and Z1P code) Exent of Authority (if licensing agreement) :

Signature of grantor (In ink) :

## Every issue (1)

- February 27, 1990: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/28/0b/280bd8ffb20b6b9454d79e60987a53918eda9ecee3c1254324aa1702a2490a2f)

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