# STC SA1320WE - Type: Supplemental type certificate - Status: Current, Reissued - Holder: Atlantic Coast Sea Planes LLC, United States - Description: G-21C: Installation of two United Aircraft of Canada Drawing List Model PT6A-20 engines. G-21D: installation of two United Aircraft of Canada Ltd Model PT6A-20 engines, Alvarez-Calderon wing flaps, and related changes. - Applied: July 28, 1965 - Status date: November 8, 2007 - Product: Aircraft, Small Multi-Engine - Certification basis: Part 21 - Data sheets: [TCDS 4A24](https://openairdocs.org/tcds/4A24) - Certificate PDF: https://openairdocs.org/files/sha256/2b/b3/2bb3848915838274586d65b5dac28879c204dbbfd04d43f45cc2f1529041836d - Approved model list and other attachments: [SA1320WE.pdf](https://openairdocs.org/files/sha256/d1/45/d14513ca69f7bbb7b38c54346fd20864753e780ffce53e80a1f78f38d7dd37ea) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0EA63CFD822F8E1386257AC200691507.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/SA1320WE ## ADs that name it (0) None. ## Approved models (2) - McKinnon A. G. G-21C ([TCDS 4A24](https://openairdocs.org/tcds/4A24)) - McKinnon A. G. G-21D ([TCDS 4A24](https://openairdocs.org/tcds/4A24)) ## 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. STC SA130WE McKinnon G-21D Feb. 16, 1967 Amended Oct 2, 07; Nov 8, 07 Supplemental Type Certificate Addendum No. SA1320WE The conditions and limitations of Aircraft Specification No. 4A24 apply except as follows: This data sheet, which is a part of Supplemental Type Certificate No. SA1320WE, prescribes conditions and limitations under which the product for which the STC was issued meets the airworthiness requirements of the Federal Aviation Regulations. The information contained herein is in addition to the conditions and limitations listed in the applicable McKinnon Enterprises FAA-approved Airplane Flight Manual. Supplemental T. C. Holder: Atlantic Coast Seaplanes, LLC 3623 N. Elm St., Suite 200 P. O. Box 41027 Greensboro, NE 27455 I – Model G-21D, 12 PCAmM (Normal Category) as modified by STC No. SA1320WE Engines Two United Ai rcraft of Canada Ltd. PT6A-20 Fuel JP-4 and JP-5 fuels conforming to Pratt & Whitney Aircraft Specification No. 552 Oil Refer to UACL PT6 Engine Service Bulletin No. 1 and Canadian Pratt & Whitney Specification No. 202 for eligible oils. Engine Ratings (Static Sea Level) Shaft Jet Equivalent Propeller Horsepower Thrust Shaft Speed lbs. Horsepower RPM For all operations except reverse 550 72 579 2200 For reverse (one 500 2100 minute) C. G. Range +24.15 to +29.5 at 12,200 lb. +19.60 to +29.5 at 10, 600 1b. Straight line variation between points given Weights Maximum takeoff 12,200 lb. Maximum landing on land 12,000 1b. Maximum landing on water 12,200 1b. Fuel Capacity Two main tanks (+30) Total 110 gal., 715 lb. each Usable 108.5 gal., 705 lb. each Two outboard auxiliary tanks (+30) Total 60 gal., 390 lb. each Usable 60 gal., 390 lb. each One Center Auxiliary tank (+30) Total 80 gal., 520 lb. Usable 60 gal., 390 lb. Note: Fuel quantity must not exceed weights shown. See Note 1(a) for system fuel. Oil Capacity 4.6 gallons to tal in two integral engine tanks of 2.3 gallons each 3.0 gallons total usable See Note 1(b) for system oil. Control Surface All controls (+) or minus (-) 1º Movements Aileron Up - 20º Down - 20º Elevator Up - 26º Down - 21º Rudder Right – 22 ½ º Left - 19 ½ º F l a p D o w n - 2 0 º For flap zero degree setting, align flap with top surface of aileron, (aileron in ne utral position) and indicator at zero. Check with protractor at 20º, allowable tolerance plus (+) or minus (-) 1º. Inboard and outboard flaps must cycle from full retract position to full extended position in 4± 1 second. Hyd. Pressure to be 800 PSI min. when operating flap, and checking cable tension. Elevator tab Up - 16º Down - 21º Rudder tab Right – 17 ½ º Left - 19 ½ º Set rudder tab 6º to the left, with indicator (in cockpit), set on 0º or take-off position. Left and right travels taken from this position STC…SA1320WE NOTE 1 Current weight and balance data including list of equipment included in the certificated empty weight, a nd loading instructions, when necessary, must be provided for each aircraft at the time of airworthiness certification for return to service. (a) The certificated empty weight and corresponding center of gravity locations must include system fuel (unusable) of 150 lb. at (+30). (b) The certificated empty weight and corresponding center of gravity locations must include system oil (unusable) of 12 lb. at (-42.5). NOTE 2: The following placards must be displayed in front of and in full view of the pilot: (a) “This airplane must be operated as a normal category airplane in compliance with the operational limitations stated in the form of placards markings and manuals.” (b) “Caution – Simultaneous operation of flap switches prohibited.” (c) “Center auxiliary tank fuel to be used in conjunction with only one main tank to feed only one engine.” The following placard must be displayed on the forward exit door: (d) “Do not open door before propellers have stopped.” The following placards must be displayed on or adjacent to the filler opening of the appropriate fuel tank: (e) Main tanks – “JP-4 or JP-5 fuels conforming to P & WA Spec. No. 522. Total capacity 110 U.S. gallons.” (f) Outboard auxiliary tanks – “JP-4 or JP-5 fuels conforming to P & WA Spec. No. 522. Total capacity 60 U.S. gallons.” (g) Center auxiliary tank – “JP-4 or JP-5 fuels conforming to P & WA Spec. No. 522. Total capacity 60 U.S. gallons.” END ### SA1320WE.pdf United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number SA1320WE This certificate, issued to Atlantic Coast Seaplanes, LLC 3623 N. Elm St., Suite 200 P. O. Box 41027 Greensboro, NE 27455 certifies that the change in the type design for the following product with the limitations and conditions therefor as specified hereon meets the airworthiness requirements of Part ** of the Regulations. ** See attached STC SA1320WE Addendum for certification basis Original Product⎯Type Certificate Number: 4A24 Make: McKinnon Model: G-21C, G-21D Description of the Type Design Change: G-21C: Installation of two United Aircraft of Canada Drawing List Model PT6A-20 engines G-21D: Installation of two United Aircraft of Canada Ltd. Model PT6A-20 engines, Alvarez-Calderon wing flaps, and related changes. See attached SA1320WE Addendum for required data Limitations and Conditions: See attached STC SA1320 Addendum which is a part of this certificate. G-21C: FAA- approved Airplane Flight Manual for the G-21C Turbo Goose is required. G-21D: FAA-approved Airplane Flight Manual for the McKinnon G-21D Turbo Goose is required for this installation. 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. This certificate and the supporting data which is the basis for approval shall remain in effect until surrendered, suspended, revoked, or a termination date is otherwise established by the Administrator of the Federal Aviation Administration. Date of application: July 28, 1965 Date reissued: June 6, 1984, September 4, 1998, October 2, 2007; November 8, 2007 Date of issuance: February 16, 1967 Date amended: October 2, 2007; By direction of the Administrator __________________________________________ (Signature) Acting Manager, Seattle Aircraft Certification Office (Title) Any alteration of this certificate is punishable by a fine of not exceeding $1,000, or imprisonment not exceeding 3 years, or both. This certificate may be transferred in accordance with FAR 21.47. **FAA FORM 8110-2(10-68)** ## Every issue (3) - November 8, 2007: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/2b/b3/2bb3848915838274586d65b5dac28879c204dbbfd04d43f45cc2f1529041836d), [SA1320WE.pdf](https://openairdocs.org/files/sha256/d1/45/d14513ca69f7bbb7b38c54346fd20864753e780ffce53e80a1f78f38d7dd37ea) - November 5, 2007: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/2b/b3/2bb3848915838274586d65b5dac28879c204dbbfd04d43f45cc2f1529041836d), [SA1320WE.pdf](https://openairdocs.org/files/sha256/d1/45/d14513ca69f7bbb7b38c54346fd20864753e780ffce53e80a1f78f38d7dd37ea) - October 2, 2007: Amended, Historical. [certificate](https://openairdocs.org/files/sha256/0f/d4/0fd4c3557ad3f280a5fd0ed6b57e6e7be519259853dc34eedf938d79cb26108d), [SA1320WE Addendum.pdf](https://openairdocs.org/files/sha256/f3/74/f374ccaced37a150c3fede9c465a933a200203d4f57e97111264c7a2f2b36853) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.