# N4AF: 1968 Cessna 421

- Status: Valid registration
- Airframe: [Cessna 421](https://openairdocs.org/model/cessna-421) (registry code 2076010, 8 seats)
- Engine: [Continental GTSIO-520-C](https://openairdocs.org/engine/continental-gtsio-520-c) (registry code 17035)
- Data sheets: [TCDS A7CE](https://openairdocs.org/tcds/A7CE) (Textron Aviation Inc.), [TCDS E7CE](https://openairdocs.org/tcds/E7CE) (Continental Aerospace Technologies, Inc.) (OpenAirDocs)
- Serial number: 421-0142
- Year built: 1968
- Type: Fixed wing multi engine
- Engine type: Reciprocating
- Airworthiness: Standard, normal
- Airworthiness date: July 11, 1968
- Certificate issued: March 25, 2023
- Expires: March 31, 2030
- Mode S code: A4A7F5
- Registered owner: [N4af LLC](https://openairdocs.org/faa-owner/N4AF%20LLC)
- Location: [Conroe, TX](https://openairdocs.org/faa-place/TX/Conroe)
- Owner type: LLC
- Owner's area on the map: 30.1867° N, 95.4290° W: Placed by OpenAirDocs at the center of ZIP code 77385, within about 3 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=4AF
- Page: https://openairdocs.org/aircraft/N4AF

From the FAA registry file of October 22, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination.

## ADs that may apply (OpenAirDocs): 50 in force

### Matched by airframe (Cessna 421)

- [AD 2023-09-09](https://openairdocs.org/ad/2023-09-09): Exhaust Turbine System (Recip) · Aerostar PA-60-600 (Aerostar 600), PA-60-601 (Aerostar 601), PA-60-601P (Aerostar 601P) and 292 more. Effective Jul 17, 2023
- [AD 2023-10-02](https://openairdocs.org/ad/2023-10-02): Indicating/Recording System, Navigation · Boeing 18, 23, 35 and 1,060 more. Effective May 26, 2023
- [AD 2018-03-03 R1](https://openairdocs.org/ad/2018-03-03-R1): Fuselage · Textron 401, 401A, 401B and 13 more. Effective May 23, 2018
- [AD 2016-17-08](https://openairdocs.org/ad/2016-17-08): Elevator Tab Control System · Textron 310, 310A, 310B and 46 more. Effective Sep 12, 2016
- [AD 2014-03-03](https://openairdocs.org/ad/2014-03-03): Placards and Markings · Cessna 310, 310A, 310B and 37 more. Effective Apr 7, 2014
- [AD 2005-20-25](https://openairdocs.org/ad/2005-20-25): Avionics bus circuit breaker switches · Cessna 401, 401A, 401B and 15 more. Effective Nov 9, 2005
- [AD 2005-18-20](https://openairdocs.org/ad/2005-18-20): "FASTprop" propeller de-icers · Hartzell PHC-C3YF-1RF/F8468A(B,K)-8R constant speed propeller (STC SA00718LA or 17 others). Effective Oct 14, 2005
- [AD 2004-25-16 R1](https://openairdocs.org/ad/2004-25-16-R1): Fuel regulator shutoff valve · Bombardier CL-215-1A10, CL-215-6B11 (CL-215T Variant), CL-215-6B11 (CL-415 Variant) and 64 more. Effective Jun 20, 2005
- [AD 2005-01-19](https://openairdocs.org/ad/2005-01-19): Mode S transponders · GARMIN International GTX 330D, GTX 330, GTX 33D and 830 more. Effective Feb 23, 2005
- [AD 2004-21-05](https://openairdocs.org/ad/2004-21-05): B-Seires Combustion Heaters · Bombardier CL-215-1A10, CL-215-6B11 (CL-215T Variant), CL-215-6B11 (CL-415 Variant) and 41 more. Effective Nov 19, 2004
- [AD 2004-08-15](https://openairdocs.org/ad/2004-08-15): TAWS8000 terrain awareness warning systems (TAWS) · Cessna 421, 500, 501 and 18 more. Effective Jun 7, 2004
- [AD 2000-01-16](https://openairdocs.org/ad/2000-01-16): Exhaust System · Cessna 320, 320-1, 320A and 28 more. Effective Feb 15, 2000
- [AD 98-25-02](https://openairdocs.org/ad/98-25-02): Top-mounted Antenna · Bell Helicopter Textron Canada 407, 172, 172A and 243 more. Effective Dec 22, 1998
- [AD 98-14-03](https://openairdocs.org/ad/98-14-03): Transponders · Cessna 172, 172A, 172B and 230 more. Effective Aug 16, 1998
- [AD 97-01-13](https://openairdocs.org/ad/97-01-13): Fuel, Oil and Hydraulic Hoses · Cessna 150, 150A, 150B and 232 more. Effective Feb 3, 1997
- [AD 96-12-22](https://openairdocs.org/ad/96-12-22): Full Flow Engine Oil Adapter · Bellanca CH-300 Pacemaker, 120, 140 and 361 more. Effective Jul 31, 1996
- [AD 92-16-18](https://openairdocs.org/ad/92-16-18): Passenger Seat Reinforcement · Cessna 401, 402, 402A and 9 more. Effective Sep 10, 1992
- [AD 90-02-13](https://openairdocs.org/ad/90-02-13): Main Landing Gear · Cessna 310, 310A, 310B and 40 more. Effective Feb 5, 1990
- [AD 87-21-02 R1](https://openairdocs.org/ad/87-21-02-R1): Fuel Filler Openings · Cessna 310D, 310E, 310F and 41 more. Effective Jun 16, 1989
- [AD 76-08-02 R2](https://openairdocs.org/ad/76-08-02-R2): Wing Tip Nose Cap · Cessna 310, 310A, 310B and 41 more. Effective Jan 31, 1983
- [AD 72-14-08 R1](https://openairdocs.org/ad/72-14-08-R1): Flexible Hose Assemblies · Cessna 310, 310A, 310B and 33 more. Effective Sep 4, 1981
- [AD 78-13-05](https://openairdocs.org/ad/78-13-05): Improperly Installed Seats · Cessna 340, 340A, 402B and 7 more. Effective Jul 5, 1978
- [AD 78-05-06](https://openairdocs.org/ad/78-05-06): Flexible Fuel Cells · Cessna 180, 182, 185 and 98 more. Effective Jun 30, 1978
- [AD 73-22-01](https://openairdocs.org/ad/73-22-01): Fuel In Wing Leading Edge · Cessna 340, 401, 401A and 11 more. Effective May 29, 1978
- [AD 76-13-07](https://openairdocs.org/ad/76-13-07): Fork Bolts · Cessna 401, 401A, 401B and 11 more. Effective Jul 7, 1976
- [AD 72-11-05](https://openairdocs.org/ad/72-11-05): Auxiliary Fuel Cell Leaks · Cessna 411, 411A, 421 and 3 more. Effective Jun 2, 1972
- [AD 72-03-07](https://openairdocs.org/ad/72-03-07): Landing Gear Failure · Cessna 310, 310A, 310B and 30 more. Effective Feb 9, 1972
- [AD 72-02-01](https://openairdocs.org/ad/72-02-01): Propeller Attachment Nuts · Cessna 411, 411A, 421 and 2 more. Effective Jan 18, 1972
- [AD 69-14-01](https://openairdocs.org/ad/69-14-01): Fuel Starvation · Cessna 310G, 310H, 310I and 22 more

### Matched by engine (Continental GTSIO-520-C)

- [AD 2023-05-16](https://openairdocs.org/ad/2023-05-16): Reciprocating Engine Power Section · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-H and 147 more. Effective Mar 15, 2023
- [AD 2023-02-12](https://openairdocs.org/ad/2023-02-12): Engine Air Intake System · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 127 more. Effective Feb 17, 2023
- [AD 2022-16-03](https://openairdocs.org/ad/2022-16-03): Engine (RECIPROCATING) · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-F and 236 more. Effective Aug 15, 2022
- [AD 2020-16-11](https://openairdocs.org/ad/2020-16-11): SUMMARY: Reciprocating Cylinder Section · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-H and 23 more. Effective Sep 21, 2020
- [AD 2016-16-12](https://openairdocs.org/ad/2016-16-12): Cylinder assemblies · Continental Motors LTSIO-520-AE, TSIO-520-A, TSIO-520-AE and 89 more. Effective Sep 15, 2016
- [AD 2012-03-06](https://openairdocs.org/ad/2012-03-06): Fuel servo diaphragm · Continental Motors 6-260-A, 6-285-A, 6-285-B and 482 more. Effective Feb 24, 2012
- [AD 2010-11-04](https://openairdocs.org/ad/2010-11-04): Hydraulic lifters · Continental Motors FSO-470-A, GIO-470-A, GTSIO-520-C and 190 more. Effective Jun 16, 2010
- [AD 2007-05-15](https://openairdocs.org/ad/2007-05-15): Starter adapter assembly · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 6 more. Effective Apr 16, 2007
- [AD 2004-08-10](https://openairdocs.org/ad/2004-08-10): Serial-numbered (SN) cylinders · Modify Teledyne Continental TSIO-520-NB engine (RAM Aircraft Limited Partnership STC SE09104SC or 4 others). Effective May 5, 2004
- [AD 99-19-01](https://openairdocs.org/ad/99-19-01): No. 2 and No. 5 Crankshaft Inspections · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 127 more. Effective Sep 30, 1999
- [AD 98-17-11](https://openairdocs.org/ad/98-17-11): Crankshafts · Continental Motors A-65-3, A-65-8, A75-8 and 90 more. Effective Oct 19, 1998
- [AD 95-21-15](https://openairdocs.org/ad/95-21-15): Aviation Gasoline · Continental Motors A-65-8, C85-12F, C85-12FJ and 77 more. Effective Nov 28, 1995
- [AD 93-10-02](https://openairdocs.org/ad/93-10-02): Missing Cylinder Valve Retainer Key · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 180 more. Effective Aug 12, 1993
- [AD 91-19-03](https://openairdocs.org/ad/91-19-03): Oil Filter · Continental Motors 6-285-A, 6-285-B, 6-285-BA and 169 more. Effective Sep 29, 1991
- [AD 88-03-06](https://openairdocs.org/ad/88-03-06): Oil Filter · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 155 more. Effective Apr 15, 1988
- [AD 86-13-04 R3](https://openairdocs.org/ad/86-13-04-R3): Cylinder Assemblies · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-H and 44 more. Effective Feb 24, 1988
- [AD 81-24-06](https://openairdocs.org/ad/81-24-06): Engine Driven Fuel Pumps · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 51 more. Effective Nov 23, 1981
- [AD 79-05-09](https://openairdocs.org/ad/79-05-09): Oil Pump Assembly Or Oil Pressure Relief Valve Screw And/Or Plunger · Teledyne Continental Motors 6-285-CA, GTSIO-520-C, GTSIO-520-D and 60 more. Effective Mar 12, 1979
- [AD 75-09-13](https://openairdocs.org/ad/75-09-13): Turbocharger Oil Inlet Adapter · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-F and 9 more. Effective Apr 24, 1975
- [AD 80-09-11](https://openairdocs.org/ad/80-09-11): Starter Torsional Damper/Starter Gear Shaft · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 6 more
- [AD 77-13-22](https://openairdocs.org/ad/77-13-22): Crankcase Cracks · Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-F and 22 more

### Historical (superseded or no longer in force)

- [AD 2018-03-03](https://openairdocs.org/ad/2018-03-03) (historical): Fuselage · Textron 401, 401A, 401B and 13 more. Effective Feb 28, 2018
- [AD 2016-07-24](https://openairdocs.org/ad/2016-07-24) (historical): Elevator Tab Control System · Textron 310, 310A, 310B and 46 more. Effective Apr 26, 2016
- [AD 2023-04-08](https://openairdocs.org/ad/2023-04-08) (historical): Reciprocating Engine Power Section · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-H and 141 more. Effective Feb 23, 2023
- [AD 2009-24-52](https://openairdocs.org/ad/2009-24-52) (historical): Hydraulic lifters · Continental Motors FSO-470-A, GIO-470-A, GTSIO-520-C and 192 more
- [AD 2009-24-51](https://openairdocs.org/ad/2009-24-51) (historical): Hydraulic lifters · Teledyne Continental Motors FSO-470-A, GIO-470-A, GTSIO-520-C and 156 more
- [AD 2005-20-04](https://openairdocs.org/ad/2005-20-04) (historical): Starter adapter assembly · Teledyne Continental Motors GTSIO-520-C, GTSIO-520-D, GTSIO-520-E and 6 more. Effective Nov 1, 2005
- [AD 94-14-12](https://openairdocs.org/ad/94-14-12) (historical): Octane Aviation Gasoline · Teledyne Continental Motors A-65-8, C85-12, E185-11 and 68 more

## Information bulletins (advisory) (18 in force)

- [SAIB CE-13-27R1](https://openairdocs.org/saib/CE-13-27R1): Flight Controls  Frayed Flap Extend Cables. Issued Jan 5, 2022
- [SAIB AIR-21-20](https://openairdocs.org/saib/AIR-21-20): TE FLAP CONTROL SYSTEM, Flight Controls –Flap Cable Tension. Issued Dec 16, 2021
- [SAIB CE-14-11R1](https://openairdocs.org/saib/CE-14-11R1): Landing Gear; Nose Landing Gear Trunnions. Issued Sep 23, 2015
- [SAIB CE-14-19](https://openairdocs.org/saib/CE-14-19): Landing Gear; Main Landing Gear (MLG) Torque Link. Issued May 30, 2014
- [SAIB CE-13-22](https://openairdocs.org/saib/CE-13-22): Electrical Power System  Circuit Breaker Switch. Issued Mar 13, 2013
- [SAIB CE-10-01](https://openairdocs.org/saib/CE-10-01): Fuel: Fuel Tank Selector Valve Systems. Issued Oct 5, 2009
- [SAIB CE-09-16](https://openairdocs.org/saib/CE-09-16): Landing Gear: Main Landing Gear Torque Tube. Issued Mar 3, 2009
- [SAIB CE-06-46R1](https://openairdocs.org/saib/CE-06-46R1): . Issued Sep 18, 2006
- [SAIB CE-03-41](https://openairdocs.org/saib/CE-03-41): . Issued Jun 27, 2003
- [SAIB ACE-99-06](https://openairdocs.org/saib/ACE-99-06): . Issued Nov 17, 1998
- [SAIB ACE-99-05](https://openairdocs.org/saib/ACE-99-05): . Issued Nov 17, 1998
- [SAIB ACE-96-05](https://openairdocs.org/saib/ACE-96-05): . Issued Oct 1, 1996
- [SAIB NE-18-16](https://openairdocs.org/saib/NE-18-16): POWERPLANT  Alternator Drive Coupling. Issued Jun 20, 2018
- [SAIB NE-16-13](https://openairdocs.org/saib/NE-16-13): Powerplant - Prohibited use of sealant. Issued Mar 8, 2016
- [SAIB NE-13-15](https://openairdocs.org/saib/NE-13-15): Engine Controls: Continental Motors, Inc. (CMI) Throttle and Mixture Control Levers. Issued Feb 8, 2013
- [SAIB NE-13-04](https://openairdocs.org/saib/NE-13-04): Continental Motors, Inc. (CMI) Connecting Rod Piston Pin Bushing Inspection. Issued Oct 31, 2012
- [SAIB NE-10-09](https://openairdocs.org/saib/NE-10-09): Reciprocating Engine Power Section: Hydraulic Valve Lifters. Issued Nov 20, 2009
- [SAIB NE-09-08](https://openairdocs.org/saib/NE-09-08): Reciprocating Engine Cylinder Section. Issued Jan 30, 2009
- [SAIB CE-14-11](https://openairdocs.org/saib/CE-14-11) (historical): Landing Gear; Nose Landing Gear Trunnions. Issued Feb 25, 2014

## NTSB investigations

None matched to N4AF.

## FAA accident and incident reports

None matched to N4AF.

## Service difficulty reports

None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model.

## STCs that may be installed (OpenAirDocs) (269, first 50)

Approved for this aircraft's airframe or engine model, in force first, then newest. The registry doesn't record which STCs an aircraft has; its records do.

### Approved for the airframe (Cessna 421)

- [STC SA01800SE](https://openairdocs.org/stc/SA01800SE): Fabrication and installation of new or replacement of existing instrument panel lights dimmer control. TCW Technologies, LLC
- [STC SA01861SE](https://openairdocs.org/stc/SA01861SE): Fabrication and installation of Landing Light Controller. TCW Technologies, LLC
- [STC SA02279AT](https://openairdocs.org/stc/SA02279AT): Installation of a Boom Beam bulb, starter, and ballast. Whelen Aerospace Technologies
- [STC SA04837NY](https://openairdocs.org/stc/SA04837NY): Installation of AeroLED's Holdings, LLC., position lights, navigation lights, strobe lights and beacon lights. AeroLED's Holdings, LLC
- [STC SA02019SE-D](https://openairdocs.org/stc/SA02019SE-D): Installation of Garmin Model GTN 625/635/650; 725/750 Navigation System. Garmin International Inc
- [STC SA800EA](https://openairdocs.org/stc/SA800EA): Installation of Whelen Anti-Collision, Position, or Anti-Collision/Position Light System, and applicable associated power supplies. Whelen Aerospace Technologies
- [STC SA00079NY](https://openairdocs.org/stc/SA00079NY): Installation of Airwolf remote mounted engine oil filter kit AFC-K008 on single and multi engine fixed wing light aircraft incorporating Teledyne Continental reciprocating engines of 450 horsepower or less. Airwolf Filter Corporation
- [STC SA02511SE](https://openairdocs.org/stc/SA02511SE): Installation of replacement fuel quantity indicator sending unit(s). CiES Inc
- [STC SA5846NM](https://openairdocs.org/stc/SA5846NM): Installation of wing tank flexible fuel cells. Aerosport Fuel Cells, LLC
- [STC SA5581SW](https://openairdocs.org/stc/SA5581SW): Installation of ALCOR true-flow/ totalizer system. Alcor LLC
- [STC SA02738CH](https://openairdocs.org/stc/SA02738CH): Installation of L-3 Communications Avionics Systems. Acron Aviation Inc
- [STC SA04046CH PAGE 1](https://openairdocs.org/stc/SA04046CH%20PAGE%201): Installation of L-3 GENESIS (TM) Electronic Standby Instrument System (ESI-500/MAG-500). Acron Aviation Inc
- [STC SA02386AK](https://openairdocs.org/stc/SA02386AK): Replacement of existing landing and/or taxi light reflector and bulbs with Light Emitting Diode (LED) lighting systems. AeroLED's Holding LLC
- [STC SA02658SE](https://openairdocs.org/stc/SA02658SE): Installation of Garmin GI 275 Multi-Function Display System. Garmin International Inc
- [STC SA02571SE](https://openairdocs.org/stc/SA02571SE): Installation of Garmin G500/G600 TXi Integrated Avionics System (Primary Flight Display, Multi-Function Display, and Engine Indicating System Display). Garmin International Inc
- [STC SA02532AT](https://openairdocs.org/stc/SA02532AT): Installation of subject Michelin tires on appropriate aircraft. For Michelin 5, 6, 8, and 10-inch rim diameter tires on General Aviation Aircraft. Michelin North America Inc
- [STC SA00756DE](https://openairdocs.org/stc/SA00756DE): Installation of Automatic Dependent Surveillance Broadcast (ADS-B) Out Equipment using a Trig Avionics TT22 Transponder and an approved Global Positioning System (GPS) Position Sensor. Peregrine
- [STC SA02010WI](https://openairdocs.org/stc/SA02010WI): Installation of the Mid-Continent Instruments & Avionics MD23 FLEX Custom Function Display (CFD). Mid-Continent Instruments and Avionics
- [STC SA197GL](https://openairdocs.org/stc/SA197GL): Install Cleveland conversion kit P/N 199-76. Kaman Corporation Aircraft Wheel and Brake LLC
- [STC SA01967WI](https://openairdocs.org/stc/SA01967WI): Use of GAMI G100UL High Octane Unleaded Avgas. General Aviation Modifications Inc
- [STC SA02203AK](https://openairdocs.org/stc/SA02203AK): Installation of FlightLogic Synthetic Vision Electronic Flight Information System (EFIS-SV). Genesys Aerosystems Inc
- [STC SA02254AK](https://openairdocs.org/stc/SA02254AK): Installation of "Single Screen", "2 or 3 Screen", "Dual Screen", or "4 or 6 screen". Genesys Aerosystems Inc
- [STC SA02444AK](https://openairdocs.org/stc/SA02444AK): Approval of the L-3 Communications NGT 9000/9000R ADS-B system installed. ADS-B Technologies LLC
- [STC SA4270SW](https://openairdocs.org/stc/SA4270SW): Mount collision avoidance lights in engine nacelle. Johnson Aviation Products
- [STC SA09856AC](https://openairdocs.org/stc/SA09856AC): Installation of BendixKing Aerowave 100 In-flight Data Link System for non-essential, non-required aircraft Cabin Systems & Equipments. Honeywell International Inc (Bendix King)
- [STC SA11174SC PAGE 1](https://openairdocs.org/stc/SA11174SC%20PAGE%201): Installation of BendixKing by Honeywell KSN 770 and KSN 765 WAAS LPV approach capable nav/comm systems. Honeywell International Inc (Bendix King)
- [STC SA02265SE](https://openairdocs.org/stc/SA02265SE): Installation of a camera housing. Airborne Sensor LLC
- [STC SA01316LA](https://openairdocs.org/stc/SA01316LA): Installation of Sandel Avionics Terrain Awareness and Warning System. Sandel Avionics LLC
- [STC SA02075SE](https://openairdocs.org/stc/SA02075SE): Installation of a Mid-Continent MD835( ) Lithium Ion Battery. Mid-Continent Instrument Co. Inc
- [STC SA10236SC](https://openairdocs.org/stc/SA10236SC): Installation of a GDC 31 Roll Steering Converter. DAC International Inc
- [STC SA03317CH](https://openairdocs.org/stc/SA03317CH): Installation of Max-Viz EVS-600 Enhanced Vision System. PECO Inc
- [STC SA02268CH](https://openairdocs.org/stc/SA02268CH): Installation of Airwolf Filter Corp. Air Oil Separator. Airwolf Filter Corporation
- [STC SA01452CH](https://openairdocs.org/stc/SA01452CH): Installation of an air ambulance conversion kit. Med-Pac Inc
- [STC SA01714WI](https://openairdocs.org/stc/SA01714WI): Installation of a Garmin transponders: (a) GTX 330/330D/33/33D with ADS-B Out functionality; (b) GTX 335/335R/345/345R with ADS-B Out and In functionality; or (c) GTX 335R/345R with ADS-B Out functionality in select airplanes installed with G950/G1000 systems. Garmin International Inc
- [STC SA2091WE](https://openairdocs.org/stc/SA2091WE): Installation of air conditioning system. Air Comm Corporation
- [STC SA00344BO PAGE 1](https://openairdocs.org/stc/SA00344BO%20PAGE%201): Installation of Parmetheus Plus LED PAR36 and PAR46 taxi and landing lights. Whelen Aerospace Technologies
- [STC SA615EA](https://openairdocs.org/stc/SA615EA): Installation of a Whelen Anti-Collision Strobe Light System as replacement for originally installed anti-collision lights. Whelen Aerospace Technologies
- [STC SA00057SE](https://openairdocs.org/stc/SA00057SE): Installation of emergency medical stretcher, oxygen, and electrical systems. LifePort LLC
- [STC SA01213CH](https://openairdocs.org/stc/SA01213CH): Install air ambulance conversion in accordance with Spectrum Aeromed Inc. Drawings as listed on AML SA01213CH, or later FAA approved revision. Spectrum Aeromed LLC dba Spectrum Aeromed
- [STC SA00744DE](https://openairdocs.org/stc/SA00744DE): Installation of the Automatic Dependent Surveillance Broadcast (ADS-B) Out Equipment using a Trig Avionics TT31 Transponder and an approved position sensor. Peregrine
- [STC SA00765DE](https://openairdocs.org/stc/SA00765DE): Installation of Automatic Dependent Surveillance Broadcast (ADS-B) Out functionality using the BendixKing KT74 Transponder and qualified position sensor. Peregrine
- [STC SA04112CH](https://openairdocs.org/stc/SA04112CH): Installation of Appareo Systems, LLC Stratus ESG ADS-B transponder. Appareo Systems LLC
- [STC SA09751DS](https://openairdocs.org/stc/SA09751DS): Installation of an S-TEC 01326 Digital Flight Control System (DFCS). S-TEC Corporation
- [STC SA04165NY](https://openairdocs.org/stc/SA04165NY): Installation of Latitude Technologies Skynode S200 Satcom system must be performed. Latitude Technologies Corporation
- [STC SA02153LA-D PAGE 1](https://openairdocs.org/stc/SA02153LA-D%20PAGE%201): Installation of Garmin G600 Primary Flight Display (PFD) and Multifunction Display (MFD) System. Garmin International Inc
- [STC SA02503AK](https://openairdocs.org/stc/SA02503AK): Installation of AMSAFE State of the Art Restraint System (SOARS) inflatable restraints. AMSAFE Inc
- [STC SA02013CH](https://openairdocs.org/stc/SA02013CH): Installation of Avidyne Corporation Traffic Advisory System (TAS). Avidyne Corporation
- [STC SA01828SE](https://openairdocs.org/stc/SA01828SE): Installation of J.P. Instruments (JPI) EDM-960 Primary Engine Data Management System. J. P. Instruments
- [STC SA01835WI](https://openairdocs.org/stc/SA01835WI): Installation of Trig Avionics TY-96 or TY-97 VHF Communications Radio. Peregrine
- [STC SA2872SW](https://openairdocs.org/stc/SA2872SW): Installation of wing nacelle locker tanks. OCR Aviation

All 269: https://openairdocs.org/aircraft/N4AF/stcs.md

## Related

- Other Cessna 421 aircraft: https://openairdocs.org/model/cessna-421/aircraft.md
- The Continental GTSIO-520-C engine: https://openairdocs.org/engine/continental-gtsio-520-c.md

---
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