# STC SA8408SW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Metrea Special Aerospace ISR Inc.
- Description: Replace the o-ring seals in the landing gear lower strut seal.
- Status date: April 29, 2025
- Data sheets: 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4, 2A4
- Certificate PDF: https://openairdocs.org/files/sha256/6a/0a/6a0a8679e85f7d6e205cd2f374ecbed21bd6b84c4ec68df2674d275322ef3770
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID132759825120250519145453.0001
- Page: https://openairdocs.org/stc/SA8408SW

## ADs that name it

None.

## Approved models (17)

- Twin Commander Aircraft Corporation 560-F (TCDS 2A4)
- Twin Commander Aircraft Corporation 680-F(P) (TCDS 2A4)
- Twin Commander Aircraft Corporation 680-FL (TCDS 2A4)
- Twin Commander Aircraft Corporation 680-FL(P) (TCDS 2A4)
- Twin Commander Aircraft Corporation 680-T (TCDS 2A4)
- Twin Commander Aircraft Corporation 680-V (TCDS 2A4)
- Twin Commander Aircraft Corporation 680-W (TCDS 2A4)
- Twin Commander Aircraft Corporation 681 (TCDS 2A4)
- Twin Commander Aircraft Corporation 685 (TCDS 2A4)
- Twin Commander Aircraft Corporation 690 (TCDS 2A4)
- Twin Commander Aircraft Corporation 690A (TCDS 2A4)
- Twin Commander Aircraft Corporation 690B (TCDS 2A4)
- Twin Commander Aircraft Corporation 690C (TCDS 2A4)
- Twin Commander Aircraft Corporation 690D (TCDS 2A4)
- Twin Commander Aircraft Corporation 695 (TCDS 2A4)
- Twin Commander Aircraft Corporation 695A (TCDS 2A4)
- Twin Commander Aircraft Corporation 695B (TCDS 2A4)

## 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.

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Original Product 7\SH&HUWLILFDWH1XPEHU Make:

SA8408SW Metrea Special Aerospace, ISR Inc.

1100 N. Broadway Ave, Suite 200 Oklahoma City, OK 73103 Part 3 Civil Air Regulations 2A4 Twin Commander 560F, 680F(P), 680FL, 680FL(P), 680T/V/W, 681, 685, 690/A/B/C/D, 695/A/B Replacement of O-ring Seals in the landing gear, lower strut seal. Data required:

1. Gulfstream Aerospace Technologies Drawing List No. GSDL-001, Rev. IR, dated April 24, 1992, and

2. Gulfstream Aerospace Technologies Installation Instructions No. GSI-001, Rev. IR, dated April 24, 1992, or later FAA Approved revisions for 1 or 2.

Compatibility of this design change with previously approved modifications must be determined by the installer.

November 1, 1991 September 14, 1998, April 29, 2025 July 17, 1992 October 13, 1992 for Paul Nguyen Manager, Central Certification Branch Compliance & Airworthiness Division Aircraft Certification Service 2

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Too (Name and address of transferee):

Date oI transfer:

SA8408SW 2

## Every issue (2)

- April 29, 2025: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/6a/0a/6a0a8679e85f7d6e205cd2f374ecbed21bd6b84c4ec68df2674d275322ef3770)
- December 4, 2006: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/83/d6/83d6937e1c2a737128fce210f8e0c897a62fbfee2d4666f60e720e4ea18d4ad3)

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From OpenAirDocs.org, an independent open copy of FAA data. Only the Federal Register edition on govinfo.gov is the official legal text of an AD.