# STC SA2-636

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Signature Flight Support Corporation, United States
- Description: Empennage modifications.
- Applied: August 29, 1958
- Status date: August 31, 2000
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A-723](https://openairdocs.org/tcds/A-723)
- Certificate PDF: https://openairdocs.org/files/sha256/43/07/43073637ade361171ec091183f3d07d1dc2c9701d69d04d5c493d7b85b86f628
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9242B6BB43C1D9F785256CC10083D4BF.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA2-636

## ADs that name it (0)

None.

## Approved models (1)

- Lockheed Martin Aeronautics Company 18 ([TCDS A-723](https://openairdocs.org/tcds/A-723))

## What the certificate says

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

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA2-636 This certificate issued to: Signature Flight Support Corporation, a Delaware Corporation 7511 Lemmon Avenue, Hangar C Dallas, TX 75209 Part SRA07 of the Civi1 Ai I Regulations.

Original Product Type Certificate Number: 723 Make: Lockheed Model: 18 Description of Type Design Change:

Empennage modifications in accordance with Howard Aero, Inc. Drawing List SD503000A dated 7/19/62, or later FAA approved revision. Modifications include saddle back fairings, angle of incidence, tail cone, and elevator extensions.

Date of Application: August 29, 1958 Date Reissued: 7/10/92; 12/21/98; 8/31/00 Date of Issuance: October 23, 1958 Date Amended: May 28, 1982 Rev. 12 By Direction of the Administrator CoPs. Frances Cox (Signature) TOMINSTRATOT Manager, Special Certification Office, Southwest Region (Title)

PAA Form 8110-2(10-68) Page 1 of 3

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number 522-636 Date of Issuance: October 23, 1958 Date Amended: May 28, 1982 Reissuance Date: August 31, 2000 Limitations and Conditions: (Continued):

1. Howard Aero, Inc. CAA Approved Lockheed 18 Airplane Flight Manual Supplement dated 10/23/58 is required with Lockheed 18 modification.

2. Modification is eligible only on Lockheed 18 airplanes with modified flap and trailing edge per STC SA2-346.

3. Eligible with or without spring cartridge assembly per Howard Aero, Inc.

Dwg. 1650 dated 8/2/58.

4. This STC is part of the basic Howard 250 and H250 Tri-Gear configurations and the modification is covered in the flight manuals for these models.

5. Compatibility of the modification with other previously approved modifications must be determined by the installer.

- END-

FAA Forn 8110-2-1(10-69) Page 3 of 3

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street ) (City, State, and ZIP 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): - Date of Transfer:

Signature of grantor (In ink):

**FAA AC 69-5536**

## Every issue (1)

- August 31, 2000: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/43/07/43073637ade361171ec091183f3d07d1dc2c9701d69d04d5c493d7b85b86f628)

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