# STC SA420SW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Braniff Airways Inc, United States
- Description: Install Dual Collins FD-108 flight director system replacing Collins ID -105 Flight Director System having dual instrumentation with single steering computer
- Applied: August 13, 1964
- Status date: June 26, 1969
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 4A21](https://openairdocs.org/tcds/4A21), [TCDS 4A28](https://openairdocs.org/tcds/4A28)
- Certificate PDF: https://openairdocs.org/files/sha256/ac/0e/ac0e67e98195bd78aa8a392b3362db5b8b19c1e6bf741b976b37d79751121ef5
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B04AC701353E092D86257DFC0057CBA7.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA420SW

## ADs that name it (0)

None.

## Approved models (4)

- 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 707-200 ([TCDS 4A21](https://openairdocs.org/tcds/4A21))
- The Boeing Company 720 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.

ftirittd States of america Bepartmcnt of transportation— Jp'ederal 3toiation administration Supplemental t^uje Certificate BA4208W Braniff Airways, Inc. Pmipot vi64osw-SP. 0. BOX 35001 rrojecT, AJ.OHUDW o Dallas, Texas 75235 .1!^^^^1^^ 4b ^^iv CiVll Air iSltau£a/tvnfr.

4A21 and 4A28 : Boeing : 707-227, 720-027, 707-1388 Install dual coning JD-108 Flight Director System replacing Collins ID -105 Flight Director System having dual instrumentation with single steering computer according to Braniff Airways Engineering Change Release 15-6U dated 7/28/6U with Addenda 1 dated 8/6/6U, 2 dated 9/1/6U and 3 dated 9/3/6>j or replacing Bendix 300 Series according to EA Ho. 8-31-21, Rev. 1 dated 6/24/69, EA Ho. 8-31-218, Rev. 1 dated 6/2W69, SA Ho. 8-3^-6l, Rev. 1 dated 6/2U/69, EA Ho. 8-34-81 Section A dated 12/19/69, EA Ho. 8-3^-81 Section B dated 3/26/70.

1. FAA Approved Airplane Flight Manual Supplemental Revision Ho. 19 dated 10/20/64 required for Boeing 707-227"

2. FAA Approved Airplane Flight Manual Supplemental Revision Ho. 6 dated 9/16/64 required for Boeing 720-027*3. FAA Approved Airplane Flight Manual Supplemental Revision Ho. 1 dated 6/26/69 required for Boeing 707-138B.4. This equipment has not been evaluated for Category II performance.

ri& /w. August 13* 1964 £/•<,&.*,*&«,</: June 26, 1969 Revision 116, 1964 ^/a£e-atn*tu/t</:

(Signature) len V. Welsh Chief. Engineering and Manufacturing Branch(Title) ___

FAA Fout 81 10-2 (10-68)

## Every issue (1)

- June 26, 1969: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/ac/0e/ac0e67e98195bd78aa8a392b3362db5b8b19c1e6bf741b976b37d79751121ef5)

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