Skip to content

Aircraft STC directory

Twin Commander Aircraft 681 STCs

The Jun 30, 2026 FAA DRS snapshot contains 36 selected supplemental type certificates with status Current whose public applicability data names the Twin Commander Aircraft 681. Use it to identify modification scope and recorded holders—not to determine serial-number effectivity, compatibility, installation approval, or commercial availability.

36
listed Current at snapshot
24
holder directories
8
modification categories
Jun 3, 2025
latest recorded revision

Modification demand surface

Other aircraft modifications10
Fuel systems6
Avionics4
Electrical systems4
Landing gear and brakes3
Flight controls3
Cargo and special mission3
Engine and powerplant3

Recorded holders

Signature Flight Support Corporation7Gulfstream Aerospace Corporation3Kaman Corporation Aircraft Wheel and Brake LLC2Floats & Fuel Cells2BHE & Associates LTD1Metrea Special Aerospace ISR Inc.1Acron Aviation Inc.1S-TEC Corporation1LifePort LLC1Paul/ Lanna Egan LLC1Aircraft Components Inc1Brittain Industries, Inc1Commuter Air Technology Inc1National Flight Services, Inc1Fliegen Works Inc.1P2 Incorporated1FFC Manufacturing1Honeywell International Inc1Aero Air, LLC1SMR Technologies Inc1

Recently revised 681 STCs

Showing the 36 most recently revised records. Each entry links to the FAA source and separates public approval data from private commercial claims.

SA1177GLElectrical systems

Install Aero Medical Products Mfg., Inc. Air Ambulance Stretcher P/N 125 using Installation Kit P/N 800 in accordance with Installation and Operating Instructions, Form EA 109K, dated April 23, 2001, or later FAA approved revisions. The Medical Oxygen System Kit P/N 807 is an FAA approved option. The Inverter/Pump Kit No. 812 may be installed in accordance with Inverter/Pump Installation Instructions, EA Form 170, dated June 9, 2001, or later FAA approved revisions.

FAA holder: Paul/ Lanna Egan LLC

View record