# STC SA3320SO

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Springer Aerospace LTD, United States
- Description: Installation of Redling hydraulic brakes. (75 SERIES STEARMAN)
- Applied: June 6, 1992
- Status date: March 18, 2004
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A-743](https://openairdocs.org/tcds/A-743)
- Certificate PDF: https://openairdocs.org/files/sha256/e8/d8/e8d87fa5294edf97e41abc10b99c024f9c9e39bbfc213c570aea89a01da3ef03
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7CB6576100765F1F86256E820050F109.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3320SO

## ADs that name it (0)

None.

## Approved models (1)

- Boeing Airplane Company Wichita Division 75 Series ([TCDS A-743](https://openairdocs.org/tcds/A-743))

## 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.

Number SA3320SO

This certificate issued to Springer Aerospace LTD.

9353 S.E. 72nd Avenue Ocala, FL 34472

Part 4A of the Civil Air Regulations.

Original Product--Type Certificate Number : A743 Make : Boeing Model : Stearman 75 Series

Description of Type Design Change: Installation of Redline Corporation hydraulic brakes in accordance with Redline Installation and Maintenance Manual, R-23, Rev. Original, dated September 4, 1992, and Redline Master Drawing List No. R-21, Rev. A, dated April 24, 1994, or later FAA approved revision.

Limitations and Conditions: This approval should not be extended to other aircraft of this model on which other previously approved modifications are incorporated unless it is determined by the installer that the interrelationship between this change and any of those other previously approved modifications will produce no adverse effect upon the airworthiness of that airplane. If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

Date of application : June 6, 1992

Date of issuance : September 15, 1992

March 18, 2004

Date amended : May 4, 1993

( Signature) Melvin D. Taylor Manager, Atlanta Aircraft Certification Office

(Title)

## Every issue (1)

- March 18, 2004: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/e8/d8/e8d87fa5294edf97e41abc10b99c024f9c9e39bbfc213c570aea89a01da3ef03)

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