FAA-listed STC holder

Atlantic Coast Sea Planes LLC STCs

The Jun 30, 2026 FAA DRS snapshot lists 20 selected supplemental type certificates with status Current under Atlantic Coast Sea Planes LLC. The records span 3 public aircraft directories and 4 modification categories. This is a research directory, not a claim that any specific kit or service is currently offered.

listed Current at snapshot

aircraft directories

modification categories

Mar 7, 2008

latest recorded revision

Modification mix

Other aircraft modifications11 Aircraft structures5 Fuel systems3 Cabin and interiors1

Aircraft represented

Grumman American Aviation G-21A18 STCs Grumman American Aviation G-2117 STCs Grumman American Aviation G-21A (Army OA-9; Navy JRF-1; -2; -3; -4; -5; and -6B)5 STCs

Recently revised records

Showing the 20 most recently revised records. Category directories provide the complete paginated discovery path.

20 displayed records.

Search every indexed record for this holder. The table below contains the recently revised records shown on this page.

Atlantic Coast Sea Planes LLC supplemental type certificates, aircraft applicability, source status and dates
STC and modification	Aircraft / model / TC	Source status and dates	Holder and authority
SA101WE Installation of picture window. Aircraft structures View record	Grumman American Aviation G-21TC TC 654 Grumman American Aviation G-21A (Army OA-9; Navy JRF-1; -2; -3; -4; -5; and -6B)TC TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Feb 13, 1962	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA108WE Modification of bulkhead station 26, blkd sta 33, cabin floor from Sta 13-29 and addition of bouyant tank between Sta 29-31. Cabin and interiors View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Oct 28, 1959	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA1589WE Installation of two United Aircraft of Canada Ltd. Model PT6-20A engines. Other aircraft modifications View record	Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Apr 4, 1967	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA1751WE Increase in main fuel tank capacity to 336 gallons. Fuel systems View record	McKinnon A G G-21CTC 4A24	Current at cited snapshot Revised Mar 7, 2008 Application: Jul 17, 1968	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA1969WE Installation of passenger seats. Other aircraft modifications View record	Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: May 22, 1969	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA2317WE Installation of dual brakes. Other aircraft modifications View record	Grumman American Aviation G-21 SeriesTC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Jan 4, 1971	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA355WE Installation of hull vents. Other aircraft modifications View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Feb 14, 1963	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-1055 Rotary beacon installation. Other aircraft modifications View record	Grumman American Aviation G-21TC 654 Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Sep 22, 1958	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-1109 Metalizing of wings aft of spar. Aircraft structures View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: May 5, 1960	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-1467 Installation of retractable tip floats. Other aircraft modifications View record	Grumman American Aviation G-21TC TC 654 Grumman American Aviation G-21A (Army OA-9; Navy JRF-1; -2; -3; -4; -5; and -6B)TC TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: May 22, 1969	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-1550 Installation of wing leading edge landing lights. Aircraft structures View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Mar 6, 1961	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-1551 Installation of electric gear retract motor. Other aircraft modifications View record	Grumman American Aviation G-21TC 654 Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Mar 6, 1961	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-677 Installation of Picture Window. Aircraft structures View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Sep 22, 1958	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-678 Installation of new nose. Other aircraft modifications View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Sep 22, 1958	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-680 Installation of windshield. Other aircraft modifications View record	Grumman American Aviation G-21TC 654 Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Sep 22, 1958	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-681 Installation of dorsal fin. Other aircraft modifications View record	Grumman American Aviation G-21TC 654 Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Sep 22, 1958	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-682 Installation of retractable float. Other aircraft modifications View record	Grumman American Aviation G-21ATC 654 Grumman American Aviation G-21TC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Sep 22, 1958	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA4-683 Installation of auxiliary fuel tanks in outboard wing sections. Fuel systems View record	Grumman American Aviation G-21TC 654 Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: Apr 2, 1962	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA59WE ONE-ONLY STC, S/N B117: Installation of a Chandler Evans AN 4100 (P/N CE 9141-AA) electric driven emergency fuel pump in place of the standard hand pump and strainer (P/N NAF 38855 Type AEL-1). (G-21A N525, S/N B117). Fuel systems View record	Grumman American Aviation G-21ATC 654	Current at cited snapshot Revised Mar 7, 2008 Application: May 1, 1961	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record
SA1320WE 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. Aircraft structures View record	McKinnon A G G-21CTC 4A24 McKinnon A G G-21DTC 4A24	Current at cited snapshot Revised Nov 8, 2007 Application: Jul 28, 1965	FAA holder: Atlantic Coast Sea Planes LLC FAA authority record