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
N521SC	Cessna 210M	Fixed-wing, single engine	Individual owner Texas	Standard	2005-06-10	Valid
N4KL	Cessna A188B	Fixed-wing, single engine	Individual owner Texas	Restricted	2005-06-08	Valid
N8050N	Beech F33A	Fixed-wing, single engine	Individual owner South Carolina	Standard	2005-06-06	Valid
N6501X	Cessna 210	Fixed-wing, single engine	Individual owner Arizona	Standard	2005-05-26	Valid
N731LA	Cessna A188B	Fixed-wing, single engine	Cmk Aerial INC Sutton, Nebraska	Restricted	2005-05-26	Valid
N6801S	Beech V35B	Fixed-wing, single engine	Individual owner Virginia	Standard	2005-05-25	Valid
N1185	Cessna A185E	Fixed-wing, single engine	Individual owner Idaho	Standard	2005-05-23	Valid
N24579	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2005-05-20	Valid
N5809S	Beech S35	Fixed-wing, single engine	Withheld at owner's request	Standard	2005-05-18	Valid
N436DG	Beech A36	Fixed-wing, single engine	Individual owner Iowa	Standard	2005-05-16	Valid
N185E	Cessna A185F	Fixed-wing, single engine	Individual owner Idaho	Standard	2005-05-12	Valid
N1847R	Cessna A185F	Fixed-wing, single engine	Nugent Properties LLC Wasilla, Alaska	Standard	2005-05-11	Valid
N2390S	Cessna 210L	Fixed-wing, single engine	Powerhawk Flyers LLC Farmington Hills, Michigan	Standard	2005-05-11	Valid
N1854R	Beech 58	Fixed-wing, multi-engine	Individual owner Alabama	Standard	2005-05-10	Valid
N8069R	Beech V35A	Fixed-wing, single engine	Double R Farm INC Clayton, New Mexico	Standard	2005-05-05	Valid
N3330M	Beech 58	Fixed-wing, multi-engine	Maine Instrument Flight Augusta, Maine	Standard	2005-05-03	Valid
N8659Q	Cessna A185F	Fixed-wing, single engine	Co-owned owner Washington	Standard	2005-05-03	Valid
N69GV	Cessna A185F	Fixed-wing, single engine	Co-owned owner Alaska	Standard	2005-04-27	Valid
N4902U	Cessna 210E	Fixed-wing, single engine	Individual owner Arkansas	Standard	2005-04-25	Valid
N1084F	Cessna A185F	Fixed-wing, single engine	Individual owner Tennessee	Standard	2005-04-20	Valid
N3968Y	Cessna 210D	Fixed-wing, single engine	Co-owned owner Washington	Standard	2005-04-18	Valid
N4986M	Beech A36	Fixed-wing, single engine	Laney Construction CO INC Murphy, North Carolina	Standard	2005-04-14	Valid
N150DR	Beech F33A	Fixed-wing, single engine	Individual owner Wisconsin	Standard	2005-04-13	Valid
N4855V	Bellanca 17-30	Fixed-wing, single engine	Glide Slope Aviation INC Myakka City, Florida	Standard	2005-04-12	Valid
N4YZ	Cessna U206G	Fixed-wing, single engine	Individual owner Idaho	Standard	2005-04-12	Valid
N36AA	Beech A36	Fixed-wing, single engine	Individual owner Maryland	Standard	2005-04-11	Valid
N6551V	Beech E33A	Fixed-wing, single engine	Northstar Bonanza LLC Flagstaff, Arizona	Standard	2005-04-06	Valid
N21827	Cessna A188B	Fixed-wing, single engine	Individual owner New Jersey	Restricted	2005-04-05	Valid
N2678Z	Bellanca 17-30A	Fixed-wing, single engine	King Canyon Buffalo INC Denver, Colorado	Standard	2005-04-04	Valid
N7715B	Beech D55	Fixed-wing, multi-engine	Individual owner California	Standard	2005-04-04	Valid
N189CR	Beech E-55	Fixed-wing, multi-engine	Pelco Investments INC Wilmington, Delaware	Standard	2005-03-30	Valid
N4890F	Cessna U206A	Fixed-wing, single engine	Skyline Sheet Metal INC Troutdale, Oregon	Standard	2005-03-28	Valid
N4585M	Beech A36	Fixed-wing, single engine	Individual owner Colorado	Standard	2005-03-24	Valid
N55JB	Beech F33A	Fixed-wing, single engine	High Point Management CO Graford, Texas	Standard	2005-03-24	Valid
N7609Q	Cessna A185F	Fixed-wing, single engine	Co-owned owner Oregon	Multiple	2005-03-23	Valid
N7165N	Beech V35A	Fixed-wing, single engine	Withheld at owner's request	Standard	2005-03-18	Valid
N890W	Beech S35	Fixed-wing, single engine	Individual owner Kansas	Standard	2005-03-11	Valid
N721CG	Beech 35-C33A	Fixed-wing, single engine	Individual owner Mississippi	Standard	2005-03-07	Valid
N8230Y	Beech F33A	Fixed-wing, single engine	Individual owner Illinois	Standard	2005-03-04	Valid
N4530F	Cessna A185E	Fixed-wing, single engine	Individual owner Arizona	Standard	2005-03-02	Valid
N40GV	Cessna U206F	Fixed-wing, single engine	Individual owner Colorado	Standard	2005-03-01	Valid
N7097N	Beech E33A	Fixed-wing, single engine	Co-owned owner California	Standard	2005-02-24	Valid
N206SU	Cessna U206F	Fixed-wing, single engine	Individual owner New York	Standard	2005-02-22	Valid
N1351G	Cessna 310R	Fixed-wing, multi-engine	310 LLC Conover, North Carolina	Standard	2005-02-15	Valid
N1868W	Beech A36	Fixed-wing, single engine	Individual owner Iowa	Standard	2005-02-10	Valid
N3350S	Cessna 210J	Fixed-wing, single engine	Individual owner California	Standard	2005-02-03	Valid
N232JB	Beech F33A	Fixed-wing, single engine	Lundell Plastics CORP Odebolt, Iowa	Standard	2005-01-26	Valid
N375W	Cessna A185F	Fixed-wing, single engine	Victory Holdings LLC Anacortes, Washington	Standard	2005-01-26	Valid
N23534	Beech F33A	Fixed-wing, single engine	Individual owner North Carolina	Standard	2005-01-24	Valid
N71GR	Beech 58	Fixed-wing, multi-engine	Individual owner Missouri	Standard	2005-01-21	Valid
N7972K	Beech S35	Fixed-wing, single engine	Co-owned owner Texas	Standard	2005-01-21	Valid
N185BV	Cessna A185F	Fixed-wing, single engine	David Aircraft Sales INC Eden Prairie, Minnesota	Standard	2005-01-20	Valid
N2489T	Navion NAVION G	Fixed-wing, single engine	Moore Robert C Edison, California	Standard	2005-01-14	Valid
N9567Q	Beech V35	Fixed-wing, single engine	Co-owned owner Illinois	Standard	2005-01-12	Valid
N1157Q	Cessna U206F	Fixed-wing, single engine	Rrc INC Madison, Mississippi	Standard	2005-01-07	Valid
N4829J	Beech 35-C33A	Fixed-wing, single engine	Midwest Aircraft Services INC Wilmington, Delaware	Standard	2005-01-07	Valid
N1203N	Aero Commander 685	Fixed-wing, multi-engine	Individual owner Michigan	Standard	2005-01-05	Valid
N129RJ	Beech A36	Fixed-wing, single engine	Co-owned owner Florida	Standard	2004-12-20	Valid
N5463J	Cessna 172N	Fixed-wing, single engine	Individual owner Arizona	Standard	2004-12-20	Valid
N185M	Cessna A185F	Fixed-wing, single engine	G-4 Air LLC Birmingham, Alabama	Standard	2004-12-17	Valid
N652DB	Beech F33A	Fixed-wing, single engine	Rocky Mountain Air LLC Lafayette, Colorado	Standard	2004-12-15	Valid
N39856	Bellanca 17-30A	Fixed-wing, single engine	Co-owned owner Texas	Standard	2004-12-07	Valid
N3042X	Cessna A185F	Fixed-wing, single engine	Mariani Nut CO INC Winters, California	Standard	2004-11-24	Valid
N185DV	Cessna A185F	Fixed-wing, single engine	Diamond V Aircraft Interests LLC Mountain Home, Texas	Standard	2004-11-23	Valid
N5193U	Cessna 206	Fixed-wing, single engine	Individual owner Utah	Restricted	2004-11-18	Valid
N7952M	Beech 95-C55	Fixed-wing, multi-engine	Cherry Winds Aviation LLC Wilmington, Delaware	Standard	2004-11-18	Valid
N1965Z	Beech S35	Fixed-wing, single engine	Bushwack Air INC Phoenix, Arizona	Standard	2004-11-10	Valid
N1342G	Cessna 310R	Fixed-wing, multi-engine	Individual owner Illinois	Standard	2004-11-09	Valid
N1817L	Beech A36	Fixed-wing, single engine	Individual owner California	Standard	2004-11-05	Valid
N2070L	Beech 58	Fixed-wing, multi-engine	Baron 70 Lima LLC Modesto, California	Standard	2004-11-05	Valid
N399PT	Beech V35A	Fixed-wing, single engine	Individual owner Idaho	Standard	2004-11-01	Valid
N77MD	Beech A36	Fixed-wing, single engine	Co-owned owner Virginia	Standard	2004-10-27	Valid
N23612	Beech F33A	Fixed-wing, single engine	Lcms Limited Durham, North Carolina	Standard	2004-10-25	Valid
N6746F	Beech F33A	Fixed-wing, single engine	Quality Motors INC Samson, Alabama	Standard	2004-10-21	Valid
N6232V	Beech 36	Fixed-wing, single engine	Co-owned owner California	Standard	2004-10-19	Valid
N5209J	Cessna 310R	Fixed-wing, multi-engine	Dallas Aero & Sales LLC Poplar, Montana	Standard	2004-10-18	Valid
N7747R	Beech 36	Fixed-wing, single engine	D2 Aviation Services LLC Wilmington, Delaware	Standard	2004-10-15	Valid
N1811Y	Beech A36	Fixed-wing, single engine	Carhonik Enterprises LLC Piney Flats, Tennessee	Standard	2004-10-12	Valid
N9309Q	Beech V35B	Fixed-wing, single engine	Individual owner Texas	Standard	2004-10-12	Valid
N8677Q	Beech S35	Fixed-wing, single engine	Little Lady INC Wilmington, Delaware	Standard	2004-10-08	Valid
N7910K	Beech S35	Fixed-wing, single engine	Co-owned owner Florida	Standard	2004-10-07	Valid
N8935M	Cessna 210L	Fixed-wing, single engine	Individual owner Alabama	Standard	2004-10-07	Valid
N2563S	Cessna 210L	Fixed-wing, single engine	Individual owner Nevada	Standard	2004-10-01	Valid
N428AK	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2004-10-01	Valid
N929RH	Cessna 206	Fixed-wing, single engine	Co-owned owner California	Standard	2004-09-30	Valid
N855D	Beech D55	Fixed-wing, multi-engine	Von Dresky INC Fort Collins, Colorado	Standard	2004-09-29	Valid
N4452W	Beech V35B	Fixed-wing, single engine	Co-owned owner Delaware	Standard	2004-09-28	Valid
N8141Y	Beech F33A	Fixed-wing, single engine	Co-owned owner Colorado	Standard	2004-09-17	Valid
N9300N	Cessna A185F	Fixed-wing, single engine	Individual owner Utah	Standard	2004-09-17	Valid
N3867G	Beech 58	Fixed-wing, multi-engine	W & S Aviation LLC Fountain Inn, South Carolina	Standard	2004-09-16	Valid
N9128H	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	2004-09-16	Valid
N9313G	Cessna A188B	Fixed-wing, single engine	Individual owner Montana	Restricted	2004-09-16	Valid
N66AF	Beech 58	Fixed-wing, multi-engine	Individual owner Missouri	Standard	2004-09-14	Valid
N32BH	Beech V35B	Fixed-wing, single engine	Individual owner Colorado	Standard	2004-09-10	Valid
N4843R	Cessna A188B	Fixed-wing, single engine	Friesenborg & Larson Custom Spraying Lc Buffalo Center, Iowa	Restricted	2004-09-10	Valid
N58SL	Beech 58	Fixed-wing, multi-engine	Home Air INC Gainesville, Georgia	Standard	2004-09-10	Valid
N696MC	Beech F33A	Fixed-wing, single engine	Co-owned owner California	Standard	2004-09-07	Valid
N72094	Cessna U206D	Fixed-wing, single engine	Individual owner Alaska	Standard	2004-09-07	Valid
N9457S	Beech 35-C33A	Fixed-wing, single engine	Individual owner Illinois	Standard	2004-08-28	Valid
N220ME	Cessna U206B	Fixed-wing, single engine	Boyle Flying Service INC Boyle, Mississippi	Standard	2004-08-27	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