Engines · piston (reciprocating) · data as of October 9, 2026

Continental IO-520 series

9,484 aircraft on the U.S. register carry a Continental IO-520 series engine, rated at about 285 horsepower. The Beechcraft V35 Bonanza is the model most often fitted with it (1,496 aircraft). The aircraft carrying it were built between 1963 and 2017.

The FAA records engines by code, usually at the level of a series ("O-320 series") rather than the exact variant; this page gathers every FAA code that reads as Continental IO-520 series. FAA spelling: IO 520 SERIES.

Fitted to model families

Model families, as a table

	aircraft
Beechcraft V35 Bonanza	1,496
Beechcraft A36 Bonanza	1,145
Cessna A185 Skywagon	1,143
Beechcraft F33 Bonanza	872
Cessna 210 Centurion	767
Cessna U206 Stationair	641
Beechcraft 58 Baron	466
Bellanca 17 Viking	456
Beechcraft S35 Bonanza	439
Cessna 310	303
Cessna A188	230
Beechcraft E-55	193

Beechcraft V35 Bonanza · Beechcraft A36 Bonanza · Cessna A185 Skywagon · Beechcraft F33 Bonanza · Cessna 210 Centurion · Cessna U206 Stationair · Beechcraft 58 Baron · Bellanca 17 Viking · Beechcraft S35 Bonanza · Cessna 310

Where they are owner's state

Texas1,047California791Alaska673Florida567Delaware326Arizona312Montana276Washington274Colorado265Georgia251

By state, as a table

	aircraft
Texas	1,047
California	791
Alaska	673
Florida	567
Delaware	326
Arizona	312
Montana	276
Washington	274
Colorado	265
Georgia	251

Kind of aircraft

Piston singles7,845 (83%)Piston twins1,371 (14%)Turboprops268 (3%)

By kind, as a table

	aircraft	share
Piston singles	7,845	83%
Piston twins	1,371	14%
Turboprops	268	3%

When the aircraft were built by decade

By decade built, as a table

	aircraft
1940	12
1950	37
1960	2,627
1970	4,534
1980	1,114
1990	189
2000	5
2010	2

What the FAA has certified, ordered and been told about the Continental IO-520 series the component layer

The design is held under 1 type certificate (E5CE, held by Continental Aerospace Technologies, INC.). The FAA has issued 30 airworthiness directives (orders that owners must comply with) that name this engine series. Operators and repair shops have filed 465 failure reports with the FAA since 1995, 26 of them in the last ten years.

FAA orders 30 airworthiness directives · newest first

2023-10-262023-17-04 · Reciprocating Engine Oil System · engine

2023-03-152023-05-16 · Reciprocating Engine Power Section · engine

2023-02-232023-04-08 · Reciprocating Engine Power Section · engine

2023-02-172023-02-12 · Engine Air Intake System · engine

2022-08-152022-16-03 · Engine (RECIPROCATING) · engine

2022-03-292022-04-04 · Reciprocating Engine Oil System · engine

All orders naming the Continental IO-520 series

Failure reports 465 since · what operators and shops told the FAA

Failure reports by year, as a table

	reports
95	15
96	2
97	1
98	1
99	5
00	37
01	48
02	58
03	46
04	35
05	62
06	17
07	18
08	17
09	10
10	20
11	15
12	13
13	9
14	10
15	12
16	4
17	2
18	1
19	2
20	2
22	1
24	2

Parts most often reported as the reports name them

Cylinder26Cylinder Head25Relay20Hub14Circuit Breaker13Antenna12Line12Bolt10Bracket9Control Cable9

Parts most reported, as a table

	reports
Cylinder	26
Cylinder Head	25
Relay	20
Hub	14
Circuit Breaker	13
Antenna	12
Line	12
Bolt	10
Bracket	9
Control Cable	9

Latest reports

2024-04-06Engine: power loss

2022-01-21None: none

2020-07-10Rod: broken

2020-01-15Turnbuckle: corroded

Certificates and bulletins

E5CEType certificate held by Continental Aerospace Technologies, INC. · 18 models listed · revised March 8, 2022

Safety bulletins 11 · advice, not orders

2020-04-06NE-20-05 · POWERPLANT - Engine Camshaft Gear Tooth Fracture

2018-06-20NE-18-16 · POWERPLANT Alternator Drive Coupling

2017-05-10NE-17-11 · POWERPLANT Engine damage as a result of kickback

2016-03-08NE-16-13 · Powerplant - Prohibited use of sealant

2013-02-08NE-13-15 · Engine Controls: Continental Motors, Inc. (CMI) Throttle and Mixture Control Levers

Sources: the FAA's type certificate data sheets, airworthiness directives, supplemental type certificates, special conditions and special airworthiness information bulletins (Dynamic Regulatory System), and the FAA's service difficulty reports. A failure report is what an operator or repair station chose to file; the counts show reporting as much as reliability, and larger and commercial fleets report more. How the systems are grouped.

Connections how this engine series links to the rest of the register

Fitted to

Beechcraft V35 Bonanza 1,496 with this engine series
Beechcraft A36 Bonanza 1,145 with this engine series
Cessna A185 Skywagon 1,143 with this engine series
Beechcraft F33 Bonanza 872 with this engine series
Cessna 210 Centurion 767 with this engine series
Cessna U206 Stationair 641 with this engine series
Beechcraft 58 Baron 466 with this engine series
Bellanca 17 Viking 456 with this engine series

Where they are

Texas 1,047 of these aircraft
California 791 of these aircraft
Alaska 673 of these aircraft
Florida 567 of these aircraft
Delaware 326 of these aircraft

Biggest operators

Bas Part Sales LLC 27 of these aircraft
International Air Services INC Trustee 12 of these aircraft
Gta Air INC 12 of these aircraft
Southern Aircraft Consultancy INC Trustee 11 of these aircraft
United States Department Of Interior 10 of these aircraft

Airworthiness

FAA orders naming the Continental IO-520 series 30 airworthiness directives
Failure reports on the Continental IO-520 series 465 reports since 1995

Analytics

The whole map of how records connect · these connections as data: /graph/engine/continental-io-520-series.json.

Aircraft newest certificates first · 9,484

Tail no.	Maker and model	Group	Owner and base	Certificate	Registered	Status
N7885L	Beech V35	Fixed-wing, single engine	Co-owned owner Arizona	Standard	2004-08-27	Valid
N53092	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2004-08-25	Valid
N23540	Beech A36	Fixed-wing, single engine	State of Iowa Iowa City, Iowa	Experimental	2004-08-23	Valid
N220TC	Cessna A185F	Fixed-wing, single engine	Individual owner Minnesota	Standard	2004-08-21	Valid
N577W	Beech 58	Fixed-wing, multi-engine	Gta Air INC Addison, Texas	Standard	2004-08-13	Valid
N6728Y	Beech V35B	Fixed-wing, single engine	Dashdale Aviation LLC Fort Dodge, Iowa	Standard	2004-08-13	Valid
N219Q	Beech S35	Fixed-wing, single engine	Individual owner North Dakota	Standard	2004-08-11	Valid
N221TL	Beech S35	Fixed-wing, single engine	Individual owner Nevada	Standard	2004-08-05	Valid
N6548C	Beech A36	Fixed-wing, single engine	Robinetti Newbeard LLC Stratford, California	Standard	2004-07-26	Valid
N185BE	Cessna A185F	Fixed-wing, single engine	Individual owner Montana	Standard	2004-07-13	Valid
N745V	Beech S35	Fixed-wing, single engine	Individual owner California	Standard	2004-07-13	Valid
N8731Q	Cessna U206F	Fixed-wing, single engine	Individual owner Massachusetts	Standard	2004-07-13	Valid
N3057W	Beech V35B	Fixed-wing, single engine	Individual owner California	Standard	2004-07-09	Valid
N3943Y	Cessna 210D	Fixed-wing, single engine	Co-owned owner Oregon	Standard	2004-06-30	Valid
N9878H	Cessna 210M	Fixed-wing, single engine	Co-owned owner Arizona	Standard	2004-06-30	Valid
N412D	Beech 58	Fixed-wing, multi-engine	Individual owner Texas	Standard	2004-06-29	Valid
N23HL	Beech A36	Fixed-wing, single engine	Individual owner California	Standard	2004-06-23	Valid
N65206	Cessna P206	Fixed-wing, single engine	Co-owned owner Colorado	Standard	2004-06-22	Valid
N31FS	Beech V35B	Fixed-wing, single engine	Strickland CORP Onida, South Dakota	Standard	2004-06-17	Valid
N7564H	Cessna A185F	Fixed-wing, single engine	Yukon Air Service INC Fairbanks, Alaska	Standard	2004-06-14	Valid
N6236V	Beech 36	Fixed-wing, single engine	Individual owner Washington	Standard	2004-06-10	Valid
N683JW	Cessna 210N	Fixed-wing, single engine	Lotela Partners LLC Avon Park, Florida	Standard	2004-06-03	Valid
N185JT	Cessna A185F	Fixed-wing, single engine	Jb Aero Services LLC Coeur D Alene, Idaho	Standard	2004-06-02	Valid
N506HP	Beech V35B	Fixed-wing, single engine	Individual owner Indiana	Standard	2004-06-02	Valid
N8159R	Beech F33A	Fixed-wing, single engine	Individual owner California	Standard	2004-06-01	Valid
N4300W	Beech A36	Fixed-wing, single engine	Private Enterprises LLC Peoria, Arizona	Standard	2004-05-26	Valid
N8105R	Beech V35B	Fixed-wing, single engine	Individual owner Indiana	Standard	2004-05-26	Valid
N585Z	Cessna A185F	Fixed-wing, single engine	Dairy Air LLC Van Nuys, California	Multiple	2004-05-21	Valid
N777US	Beech 95-C55	Fixed-wing, multi-engine	Individual owner Tennessee	Standard	2004-05-20	Valid
N556AT	Cessna 206	Fixed-wing, single engine	Adventure Partners LLC Mercer Island, Washington	Standard	2004-05-19	Valid
N46BB	Beech D55	Fixed-wing, multi-engine	Individual owner Tennessee	Standard	2004-05-17	Valid
N5895S	Beech S35	Fixed-wing, single engine	Individual owner New Mexico	Standard	2004-05-14	Valid
N10BS	Beech E-55	Fixed-wing, multi-engine	B R S Leasing INC Wilmington, Delaware	Standard	2004-05-13	Valid
N93743	Bellanca 17-30A	Fixed-wing, single engine	Leonards Exchange Portrait Studio INC Saint Augustine, Florida	Standard	2004-05-12	Valid
N9467S	Beech V35	Fixed-wing, single engine	V35 LLC Portland, Oregon	Standard	2004-05-12	Valid
N8138R	Beech A36	Fixed-wing, single engine	Co-owned owner California	Standard	2004-05-10	Valid
N5838K	Beech S35	Fixed-wing, single engine	Individual owner Oklahoma	Standard	2004-05-06	Valid
N113JT	Beech A36	Fixed-wing, single engine	Aerotransplant INC Marfa, Texas	Standard	2004-05-05	Valid
N217P	Beech F33A	Fixed-wing, single engine	Danford Air INC Wilmington, Delaware	Standard	2004-05-05	Valid
N67249	Beech F33A	Fixed-wing, single engine	Individual owner North Carolina	Standard	2004-04-23	Valid
N771RB	Beech S35	Fixed-wing, single engine	Individual owner California	Standard	2004-04-23	Valid
N12DM	Cessna A185F	Fixed-wing, single engine	Island Airways LLC Marion, Wisconsin	Standard	2004-04-21	Valid
N8081V	Cessna A188	Fixed-wing, single engine	Storm Flying Service LLC David City, Nebraska	Restricted	2004-04-21	Valid
N233ES	Beech F33A	Fixed-wing, single engine	Spain Aviation LLC Lynchburg, Virginia	Standard	2004-04-16	Valid
N4467S	Beech A36	Fixed-wing, single engine	K & M Leasing INC Camden, Arkansas	Standard	2004-04-14	Valid
N7818R	Beech 36	Fixed-wing, single engine	Rkn Aviation LLC Cincinnati, Ohio	Standard	2004-04-14	Valid
N761PV	Cessna 210M	Fixed-wing, single engine	Individual owner Washington	Standard	2004-04-05	Valid
N72452	Beech F33A	Fixed-wing, single engine	Co-owned owner Arkansas	Standard	2004-03-29	Valid
N39820	Bellanca 17-30A	Fixed-wing, single engine	Individual owner South Dakota	Standard	2004-03-23	Valid
N2730R	Beech F33A	Fixed-wing, single engine	Rp Aviation INC Alliance, Ohio	Standard	2004-03-22	Valid
N8787Z	Cessna P206D	Fixed-wing, single engine	King Farm Partnership Mccrory, Arkansas	Standard	2004-03-22	Valid
N93759	Bellanca 17-30A	Fixed-wing, single engine	Individual owner New Mexico	Standard	2004-03-22	Valid
N364EL	Beech F33A	Fixed-wing, single engine	Individual owner California	Standard	2004-03-16	Valid
N61747	Cessna A185F	Fixed-wing, single engine	Lakes Aircraft LLC Little Canada, Minnesota	Standard	2004-03-09	Valid
N6662V	Bellanca 17-30	Fixed-wing, single engine	Individual owner South Carolina	Standard	2004-03-09	Valid
N369G	Beech 36	Fixed-wing, single engine	Individual owner Texas	Standard	2004-03-05	Valid
N6688E	Beech V35B	Fixed-wing, single engine	Individual owner Oklahoma	Standard	2004-03-04	Valid
N5952F	Cessna 210H	Fixed-wing, single engine	Individual owner Mississippi	Standard	2004-03-03	Valid
N6593U	Beech 58	Fixed-wing, multi-engine	Wedt LLC Wilmington, Delaware	Standard	2004-02-27	Valid
N1099F	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2004-02-26	Valid
N233DF	Beech F33A	Fixed-wing, single engine	Individual owner Texas	Standard	2004-02-25	Valid
N2830A	Beech A36	Fixed-wing, single engine	Marathon Heater INC Del Rio, Texas	Standard	2004-02-23	Valid
N154M	Beech A36	Fixed-wing, single engine	Napier Aircraft INC Wilmington, Delaware	Standard	2004-02-18	Valid
N185KD	Cessna A185F	Fixed-wing, single engine	Center Sea Plane Club INC Sauk Centre, Minnesota	Standard	2004-02-18	Valid
N79TH	Cessna 210D	Fixed-wing, single engine	Individual owner Alabama	Standard	2004-02-13	Valid
N9109S	Beech A36	Fixed-wing, single engine	Thomas Timber INC Harrells, North Carolina	Standard	2004-02-10	Valid
N4733M	Beech 58	Fixed-wing, multi-engine	Individual owner Minnesota	Standard	2004-02-06	Valid
N7984M	Beech 35-C33A	Fixed-wing, single engine	84M LLC Bixby, Oklahoma	Standard	2004-02-05	Valid
N442AK	Cessna 310R	Fixed-wing, multi-engine	Kelly Aviation INC Tampa, Florida	Standard	2004-02-03	Valid
N5853S	Beech S35	Fixed-wing, single engine	Individual owner California	Standard	2004-01-30	Valid
N7396U	Cessna 207A	Fixed-wing, single engine	Alaska Aircraft Leasing LLC Silverdale, Washington	Standard	2004-01-27	Valid
N9467Q	Beech 58	Fixed-wing, multi-engine	AG Aero INC Tallulah, Louisiana	Standard	2004-01-27	Valid
N18356	Beech A36	Fixed-wing, single engine	N18356 LLC Hayden, Idaho	Standard	2004-01-24	Valid
N3781Q	Beech V35	Fixed-wing, single engine	Individual owner Texas	Standard	2004-01-22	Valid
N1206F	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2004-01-21	Valid
N2296V	Beech D55	Fixed-wing, multi-engine	Individual owner Washington	Standard	2004-01-21	Valid
N674DM	Beech F33A	Fixed-wing, single engine	Bravo Aviators LLC Argyle, Iowa	Standard	2004-01-14	Valid
N81WA	Cessna 310R	Fixed-wing, multi-engine	Admiral Aviation INC New Castle, Delaware	Standard	2004-01-12	Valid
N5905S	Beech V35	Fixed-wing, single engine	Co-owned owner Indiana	Standard	2004-01-09	Valid
N5FW	Beech E-55	Fixed-wing, multi-engine	Individual owner Texas	Standard	2004-01-08	Valid
N2113F	Cessna U206	Fixed-wing, single engine	Co-owned owner Idaho	Standard	2004-01-02	Valid
N520L	Walker Dale A Jr LANCAIR LEGACY	Fixed-wing, single engine	Individual owner Colorado	Experimental	2004-01-02	Valid
N74BT	Beech A36	Fixed-wing, single engine	Sta Aviation LLC Wilmington, Delaware	Standard	2003-12-30	Valid
N711RB	Beech V35A	Fixed-wing, single engine	Co-owned owner Minnesota	Standard	2003-12-22	Valid
N185TB	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2003-12-19	Valid
N2767T	Beech V35	Fixed-wing, single engine	Individual owner Arkansas	Standard	2003-12-18	Valid
N8368Q	Cessna U206F	Fixed-wing, single engine	Individual owner California	Standard	2003-12-17	Valid
N99NP	Beech A36	Fixed-wing, single engine	Colonial Export INC Pompton Plains, New Jersey	Standard	2003-12-16	Valid
N277RB	Beech S35	Fixed-wing, single engine	Waldo Pepper Flying CO Wilmington, Delaware	Standard	2003-12-10	Valid
N401CF	Cessna 401	Fixed-wing, multi-engine	Individual owner California	Standard	2003-12-10	Valid
N741JB	Beech V35A	Fixed-wing, single engine	Individual owner Arizona	Standard	2003-12-09	Valid
N6073S	Beech A36	Fixed-wing, single engine	Co-owned owner Texas	Standard	2003-12-05	Valid
N1854F	Cessna 210F	Fixed-wing, single engine	Individual owner Minnesota	Standard	2003-12-03	Valid
N39889	Bellanca 17-31ATC	Fixed-wing, single engine	Individual owner Louisiana	Standard	2003-11-25	Valid
N4194W	Cessna A185E	Fixed-wing, single engine	Individual owner Alaska	Standard	2003-11-21	Valid
N722SJ	Cessna U206F	Fixed-wing, single engine	Individual owner Illinois	Standard	2003-11-21	Valid
N207NN	Cessna 207	Fixed-wing, single engine	Individual owner New Jersey	Standard	2003-11-10	Valid
N5817K	Beech 35-C33	Fixed-wing, single engine	Munsch James R Algonquin, Illinois	Standard	2003-11-10	Valid
N3356S	Cessna 210J	Fixed-wing, single engine	Bbt INC Wilmington, Delaware	Standard	2003-11-08	Valid
N3972G	Cessna U206C	Fixed-wing, single engine	County of Merced Sheriff'S Dept Merced, California	Standard	2003-11-03	Valid

Source: FAA Civil Aviation Registry, Releasable Aircraft Database (the engine reference table and each aircraft's engine code), October 9, 2026. Horsepower and thrust are the FAA's figures for the series, not for a particular aircraft.

	reports
95	15
96	2
97	1
98	1
99	5
00	37
01	48
02	58
03	46
04	35
05	62
06	17
07	18
08	17
09	10
10	20
11	15
12	13
13	9
14	10
15	12
16	4
17	2
18	1
19	2
20	2
22	1
24	2

	reports
95	15
96	2
97	1
98	1
99	5
00	37
01	48
02	58
03	46
04	35
05	62
06	17
07	18
08	17
09	10
10	20
11	15
12	13
13	9
14	10
15	12
16	4
17	2
18	1
19	2
20	2
22	1
24	2

	reports
95	15
96	2
97	1
98	1
99	5
00	37
01	48
02	58
03	46
04	35
05	62
06	17
07	18
08	17
09	10
10	20
11	15
12	13
13	9
14	10
15	12
16	4
17	2
18	1
19	2
20	2
22	1
24	2