# Lycoming IO-720-D1CD

- Type: Engine model (FAA registry)
- Registry code: 41959
- Manufacturer (registry): LYCOMING
- Model: IO-720-D1CD
- Engine type: Reciprocating
- Power: 400 hp
- Data sheet: [TCDS 1E15](https://openairdocs.org/tcds/1E15) (OpenAirDocs)
- Holder: Textron Lycoming Subsidiary of Textron Inc.
- Installed in: 1 registered aircraft
- Page: https://openairdocs.org/engine/lycoming-io-720-d1cd

Model codes come from the FAA registry's reference file.

## ADs that may apply (OpenAirDocs)

Matched to this engine model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment.

- [AD 2026-04-11](https://openairdocs.org/ad/2026-04-11): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 605 more. Effective Apr 8, 2026
- [AD 2015-19-07](https://openairdocs.org/ad/2015-19-07): Fuel injector fuel lines · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1B and 187 more. Effective Nov 3, 2015
- [AD 2012-19-01](https://openairdocs.org/ad/2012-19-01): Crankshafts · Lycoming Engines AEIO-360-A1A, AEIO-360-A1B, AEIO-360-A1B6 and 321 more. Effective Oct 24, 2012
- [AD 2010-07-08](https://openairdocs.org/ad/2010-07-08): Turbochargers · Kelly Aerospace Energy Systems HIO-360-E1AD, HIO-360-E1BD, HIO-360-F1AD and 137 more. Effective Apr 19, 2010
- [AD 2004-10-14](https://openairdocs.org/ad/2004-10-14): Crankshaft gear · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 642 more. Effective Jun 25, 2004
- [AD 2003-14-03](https://openairdocs.org/ad/2003-14-03): Rotary fuel pumps · Lycoming Engines AEIO-540-D4A5, AEIO-540-D4B5, AEIO-540-D4C5 and 262 more. Effective Aug 14, 2003
- [AD 2002-12-07](https://openairdocs.org/ad/2002-12-07): Oil Filter Converter Plate Gasket or the Converter Plate Kit · Lycoming Engines HIO-360-E1AD, HIO-360-E1BD, HIO-360-F1AD and 95 more. Effective Jul 3, 2002
- [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 97-15-11](https://openairdocs.org/ad/97-15-11): Cylinder kits · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 538 more. Effective Aug 12, 1997
- [AD 92-12-05](https://openairdocs.org/ad/92-12-05): Piston Pins · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 532 more. Effective Jul 10, 1992
- [AD 79-04-05](https://openairdocs.org/ad/79-04-05): Regulator Diaphragm Stem Assembly · Lycoming Engines AEIO-320-D1B, AEIO-320-E1A, AEIO-320-E1B and 215 more. Effective Sep 26, 1979
- [AD 79-12-07](https://openairdocs.org/ad/79-12-07): Magnetos · Bendix Magnetos, TIO-540-F2BD, TIO-540-N2BD and 3 more. Effective Jun 19, 1979
- [AD 78-23-10](https://openairdocs.org/ad/78-23-10): Center Body Bellows Seal Assembly · Lycoming Engines AEIO-320-D1B, AEIO-320-E1A, AEIO-320-E1B and 218 more. Effective Nov 7, 1978

Historical (superseded or no longer in force):

- [AD 2011-26-04](https://openairdocs.org/ad/2011-26-04) (historical): Externally mounted fuel injector fuel lines · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1B and 186 more. Effective Jan 25, 2012
- [AD 2011-15-10](https://openairdocs.org/ad/2011-15-10) (historical): Fuel servos · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 256 more. Effective Aug 16, 2011
- [AD 2008-14-07](https://openairdocs.org/ad/2008-14-07) (historical): Externally mounted fuel injector fuel lines · Textron Lycoming, AVCO AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1B and 185 more. Effective Aug 14, 2008
- [AD 2002-26-01](https://openairdocs.org/ad/2002-26-01) (historical): Fuel injector fuel lines · Textron Lycoming, AVCO IGO-480-A1B6, IGO-540-B1A, IGO-540-B1C and 178 more. Effective Jan 31, 2003
- [AD 2000-18-53](https://openairdocs.org/ad/2000-18-53) (historical): Oil Filter Converter Plate Gaskets · Textron Lycoming, AVCO AEIO-540, IO-360-A1B6D, IO-360-A1D6D and 73 more
- [AD 98-18-12](https://openairdocs.org/ad/98-18-12) (historical): Fuel Pump · Textron Lycoming, AVCO AEIO-540-D4A5, AEIO-540-D4B5, AEIO-540-D4C5 and 249 more. Effective Sep 28, 1998

## Information bulletins (advisory) (2)

- [SAIB NE-08-32R1](https://openairdocs.org/saib/NE-08-32R1): Propeller Governor  Idler Gear Shaft Set Screw. Issued May 13, 2016
- [SAIB NE-08-26R3](https://openairdocs.org/saib/NE-08-26R3): Magneto/Distributor. Issued Mar 31, 2011

## Registered aircraft (1)

- [N3945E](https://openairdocs.org/aircraft/N3945E): [Georgeson Troy D](https://openairdocs.org/faa-owner/GEORGESON%20TROY%20D), [Sheyenne, ND](https://openairdocs.org/faa-place/ND/Sheyenne), built 1978, S/N 36-7802066

## NTSB investigations (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB CEN15LA405](https://openairdocs.org/ntsb/CEN15LA405), Sep 9, 2015: Piper PA-36-375 (N1057E), Elmwood, NE, substantial damage. Probable cause: The pilot’s decision to take off with the airplane near its maximum gross weight from a runway that did not have sufficient length for the airplane to achieve a normal takeoff and positive climb rate…

## FAA accident and incident reports (1)

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [Accident 20150909016109A](https://openairdocs.org/incident/20150909016109A), Sep 9, 2015: Piper PA-36-375 (N1057E), Elmwood, NE, Substantial damage. The aircraft departed a sod strip of approximately 2,800 feet during day VMC conditions. The operation was under 14 CFR 137 to conduct an aerial application of…

## STCs that may be installed (OpenAirDocs) (23)

Approved for this engine model: the STC's model list names it on its data sheet, or a series that includes it. In force first, then newest. The registry doesn't record which STCs an aircraft has.

- [STC SE00825WI](https://openairdocs.org/stc/SE00825WI): Installation of Specialty Products Spin-on oil filter on Lycoming Engines. B & C Specialty Products Inc
- [STC SE02352CH](https://openairdocs.org/stc/SE02352CH): Installation of Challenger cleanable oil filter assembly. Challenger Aviation Products Inc
- [STC SE00939WI](https://openairdocs.org/stc/SE00939WI): Installation of B&C Specialty Products Model BC 315-( ) Starter on Lycoming engines. B & C Specialty Products Inc
- [STC SE01966WI](https://openairdocs.org/stc/SE01966WI): Use of GAMI G100UL High Octane Unleaded Avgas in spark ignition piston aircraft engines. General Aviation Modifications Inc
- [STC SE8628SW](https://openairdocs.org/stc/SE8628SW): Installation of oil nozzles for lubrication of cam and filters. Cygnet Aerospace Corp
- [STC SE09445SC](https://openairdocs.org/stc/SE09445SC): Installation of fuel injector nozzles. General Aviation Modifications Inc. Lists IO-720 Series
- [STC SE4408SW](https://openairdocs.org/stc/SE4408SW): Miscellaneous engine cylinder replacement parts. Continental Motors, Inc. Lists IO-720 Series
- [STC SE7506SW](https://openairdocs.org/stc/SE7506SW): Installation of any or all parts listed on Airmotive Engineering Drawing List No. 852-1, Rev. 1, dated 10/4/88, or later FFA approved revision. Continental Motors, Inc. Lists IO-720 Series
- [STC SE7670SW](https://openairdocs.org/stc/SE7670SW): Installation of parts listed on Drawing List No. 8810-3, Rev 6. Continental Motors, Inc. Lists IO-720 Series
- [STC SE8776SW](https://openairdocs.org/stc/SE8776SW): Installation of coated cylinders and piston rings. Continental Motors, Inc. Lists IO-720 Series
- [STC SE00226NY](https://openairdocs.org/stc/SE00226NY): Replacement of Lycoming starter with SKY-TEC 24-volt starter Models 149-24HT and 122-24HT. Approval limited to 24-volt DC source available to the starter. Hartzell Engine Technologies, LLC
- [STC SE2902NM](https://openairdocs.org/stc/SE2902NM): Lycoming valve cover gasket. Real Gaskets Tennessee
- [STC SE7582SW](https://openairdocs.org/stc/SE7582SW): Grinding of high compression NITRIDED Cylinders to .010 oversize, as an alternative to chrome plating or rebarreling, and the installation of SL10207 P10 Piston, SL74241 P10 Top and second compression ring, and SL 73857 P10 oil control ring. Superior Air Parts, Inc
- [STC SE01930NY](https://openairdocs.org/stc/SE01930NY): Installation of Casper Labs 90 degree oil filter housing adapter. Casper Labs Inc
- [STC SE1779NM](https://openairdocs.org/stc/SE1779NM): Installation of Precise Flight, Inc. Standby Vacuum System SVS III. Precise Flight Inc
- [STC SE09492SC](https://openairdocs.org/stc/SE09492SC): Installation and usage of Exxon 20W50 multigrade aircraft engine oil conforming to Exxon Oil formulation WS-3013. Exxon Company USA. Lists IO-720 Series
- [STC SE00350SE](https://openairdocs.org/stc/SE00350SE): Installation of sump mounted chip detector. Aviation Development Corporation
- [STC SE00299WI](https://openairdocs.org/stc/SE00299WI): Installation of B & C Specialty Products lightweight (10.2 pounds) engine starter P/N BC315-100-1(12 volts) or P/N BC 315-100-3(24 volts). Bainbridge William C III
- [STC SE8023SW](https://openairdocs.org/stc/SE8023SW): Installation and usage of AEROSHELL. Shell Development Co. Lists IO-720 Series
- [STC SE452NE](https://openairdocs.org/stc/SE452NE): Installation and usage of 'Mobil AV 1' aviation oil. Mobil Research & Development Corp. Lists IO-720 Series
- [STC SE5879SW](https://openairdocs.org/stc/SE5879SW): Use of Phillips X/C II 20W-50 and25W-60 oil (OSS 55875) in all Avco reciprocating aircraft engines from 65 to 450 BHP. Phillips Petroleum Co. Lists IO-720 Series
- [STC SE5924SW](https://openairdocs.org/stc/SE5924SW): Installation of stainless steel replacement exhaust studs on AVCO engines. Perrigo & Steele Aircraft Engr Company. Lists IO-720 Series
- [STC SE128NE](https://openairdocs.org/stc/SE128NE): Use of AMS/OIL 15W 50 synthetic piston aircraft oil in Avco engines. AMS/OIL. Lists IO-720 Series

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