# STC SA1820NM

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Dusters and Sprayers Supply, Inc, United States
- Description: Installation of Hamilton Standard 2B20-317/6135A-15 propeller converted to fixed pitch configuration.
- Applied: October 12, 1982
- Status date: October 18, 1985
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A-743](https://openairdocs.org/tcds/A-743)
- Certificate PDF: https://openairdocs.org/files/sha256/3b/59/3b59050fb26bb9748ce1ea076b2ac673d74ffd3b2f8cb4440ce245841c2bba8b
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/47B5389412CCF7D785256CC10083D124.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA1820NM

## ADs that name it (0)

None.

## Approved models (3)

- Boeing Airplane Company Wichita Division A75N1 (Army PT-17; -17A; Navy N2S-1; -4) ([TCDS A-743](https://openairdocs.org/tcds/A-743))
- Boeing Airplane Company Wichita Division B75N1 (Navy N2S-3) ([TCDS A-743](https://openairdocs.org/tcds/A-743))
- Boeing Airplane Company Wichita Division D75N1 (Army PT-27) ([TCDS A-743](https://openairdocs.org/tcds/A-743))

## What the certificate says

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

ASW-150 United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number 5A1320NM This certificate issued to: Dusters and Sprayers Supply, Inc.

Part 49 of the CIVIL AIT Regulations Original Product - Type Bertificate Number: A-743 Make Boeing Model: A75N1, B75N1, D75N1 Description of Type Design Change: Installation of Hamilton Standard 2B20-317/6135A-15 propeller converted to fixed pitch configuration in accordance with Hawthorne Aircraft Industries Conversion Instructions No. 1001, dated November 12, 1982 (2 pages) .

Limitations and Conditions: The approval of this change in type design applies to the basic aircraft of the specified models that are otherwise unmodified.

approval should not be extended to other specific airplanes of these models on which other previously approved modifications are incorporated unless it is determined that the interrelationship between this change and any of those other previously approved modifications will introduce no adverse effect upon the airworthiness of that aircraft.

BLOMER, Manager Western Aircraft Certification Office (Title)

47.

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) (I) 12-2-82 Number SA1820NM (R) 10-18-35 Supplemental Type Certificate ADDENDUM NO. SA1820NM This addendum, which is part of Supplemental Type Certificate No. SA1320NM prescribes conditions and limitations under which the product for which the Supplemental Type Certificate was issued meets the airworthiness requirements of the Civil Air Regulations. This Addendum supersedes Aircraft Specification No. A- 743 only where noted.

I - Model Boeing A75N1, B75N1, D75N1 as modified by STC SA1320NM Engine: Continental W-570-5A, -5N Propeller: Hamilton Standard 2B20-317/6135A-15 (Fixed Pitch) Hub Model: 2B20 Blade Model: 5135A-15 Diameter Limits: 93 inches maximum 93 inches minimum Pitch Setting: 13 1/2°, ‡ 1/2° Fixed Pitch measured at the 42 inch station Static RPM Limits: 1775 RPM Minimum 1925 RPM Maximum END

FAA FORM 8110-2-1 (10-69) PAGE 3 OF 3 PAGES FAA AC 82:03578

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and 21P code ) from (Name of grantor) (Print or type).

(Address of grantor) (Number and street) (City, State, and ZIP code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

c FAA AC 69-5536

## Every issue (1)

- October 18, 1985: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/3b/59/3b59050fb26bb9748ce1ea076b2ac673d74ffd3b2f8cb4440ce245841c2bba8b)

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