# STC SA4-20

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Jay Waldren, United States
- Description: Removed Howard cowling and mounting brackets and installed BT-13 cowling and mounting brackets.
- Applied: January 26, 1956
- Status date: February 14, 1956
- Product: Aircraft, Small Airplane
- Data sheets: [TCDS A-717](https://openairdocs.org/tcds/A-717)
- Certificate PDF: https://openairdocs.org/files/sha256/4b/9f/4b9faf94b09550c6d00b72a475143ee92351eb29a0571c47a16dc0e4625f943e
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/BA172489A7E9DA1586257CD30047CF76.0001
- DRS record last changed: January 29, 2026
- Page: https://openairdocs.org/stc/SA4-20

## ADs that name it (0)

None.

## Approved models (1)

- Howard Aircraft Foundation DGA-15P (Army UC-70; Navy GH-1; -2; -3; NH-1) ([TCDS A-717](https://openairdocs.org/tcds/A-717))

## What the certificate says

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

Form LA-134 11/22/55 U. S. Department of Commerce Instructions: This application to Civil Aeronautics Administration be submitted in triplicate. Information for items 1 thru 5 to be supplied by the applicant.

Supplemental Type Certificate Date January 26, 1956

1. Name of Applicant 2. Address Jay Waldren Balers feld, Cal 716 Arvin Street За Supplemental Type Certificate Applied For:

Aircraft Engine Propeller Appliance

4. Original Model Designation HOWARD D G A 15-P New Model Designation (if desired)

5. Description of Change Removed Howard cowling and mounting brackets and installed BT-13 cowling and mounting brackets. BT-13 cowling altered only to allow accessory section doors to open and by placing exhaust opening on left side. See attached drawings and photographs for all informetion regarding changes nade.

**TO BE COMPLETED BY CAA**

6. Nature and location of data On file in IA 245 Original Type Certificate No. APPROVED:

T0672 Shorts N. Hate 4Armer He Alcorn Supplemental Type Certificate No.

SAL -20 Chief, Aircraft Engineering Division Date of Approval 1A-215 201/1~56

## Every issue (1)

- February 14, 1956: Issued, Current. [certificate](https://openairdocs.org/files/sha256/4b/9f/4b9faf94b09550c6d00b72a475143ee92351eb29a0571c47a16dc0e4625f943e)

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