Engines · piston (reciprocating) · data as of October 8, 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
N70462	Cessna A185F	Fixed-wing, single engine	Co-owned owner Alaska	Multiple	1987-05-14	Valid
N185JE	Cessna A185F	Fixed-wing, single engine	Individual owner Utah	Standard	1987-04-21	Valid
N8309N	Beech V35A	Fixed-wing, single engine	Individual owner Massachusetts	Standard	1987-03-18	Valid
N9459M	Cessna U206G	Fixed-wing, single engine	Civil Air Patrol INC Maxwell Afb, Alabama	Standard	1987-03-18	Valid
N318G	Beech 35-C33A	Fixed-wing, single engine	Aero Fliers INC Akron, Ohio	Standard	1987-03-13	Valid
N68FJ	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Wisconsin	Standard	1987-03-13	Valid
N444CL	Cessna 210L	Fixed-wing, single engine	K G L Aviation INC Villisca, Iowa	Standard	1987-03-05	Valid
N185PG	Cessna A185F	Fixed-wing, single engine	Janie Gee Aviation INC Hilbert, Wisconsin	Standard	1987-02-27	Valid
N9041S	Beech S35	Fixed-wing, single engine	Individual owner Illinois	Standard	1987-01-31	Valid
N14872	Cessna U206	Fixed-wing, single engine	Individual owner Arizona	Standard	1987-01-16	Valid
N5265C	Cessna 310R	Fixed-wing, multi-engine	Workman Aircraft CO INC Largo, Florida	Standard	1987-01-13	Valid
N6648J	Beech A36	Fixed-wing, single engine	Windward Passage Corporation Englewood, New Jersey	Standard	1986-12-03	Valid
N732AV	Cessna 210L	Fixed-wing, single engine	Individual owner New Jersey	Standard	1986-11-28	Valid
N9664K	Cessna A188B	Fixed-wing, single engine	Usda Aphis Ppq Edinburg, Texas	Restricted	1986-11-05	Valid
N1582Q	Cessna A185F	Fixed-wing, single engine	Individual owner California	Standard	1986-11-03	Valid
N28195	Bellanca 17-30A	Fixed-wing, single engine	Richard C Rinks & Assoc INC Cookeville, Tennessee	Standard	1986-11-03	Valid
N9623R	Cessna U206G	Fixed-wing, single engine	United States Department of Interior Boise, Idaho	Multiple	1986-10-02	Valid
N6582Q	Beech A36	Fixed-wing, single engine	Individual owner Illinois	Standard	1986-09-19	Valid
N1266R	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Minnesota	Standard	1986-09-11	Valid
N756GF	Cessna U206G	Fixed-wing, single engine	Individual owner North Carolina	Standard	1986-09-11	Valid
N8299R	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Oklahoma	Standard	1986-08-22	Valid
N163U	Beech 36	Fixed-wing, single engine	Individual owner Texas	Standard	1986-08-18	Valid
N342EA	Cessna U206G	Fixed-wing, single engine	African Inland Mission International Peachtree City, Georgia	Standard	1986-08-13	Valid
N1825Q	Cessna A185F	Fixed-wing, single engine	Individual owner California	Standard	1986-07-16	Valid
N4673F	Cessna P206A	Fixed-wing, single engine	Co-owned owner Virginia	Standard	1986-07-02	Valid
N4881Q	Cessna A188B	Fixed-wing, single engine	Air Dakota Flite INC. Hettinger, North Dakota	Restricted	1986-07-01	Valid
N8139R	Beech F33A	Fixed-wing, single engine	Individual owner Arizona	Experimental	1986-06-24	Valid
N1834W	Beech V35B	Fixed-wing, single engine	Tri-Aero of Grand Rapids Ada, Michigan	Standard	1986-06-20	Valid
N185JA	Cessna A185E	Fixed-wing, single engine	Individual owner Minnesota	Standard	1986-04-29	Valid
N666CN	Beech A36	Fixed-wing, single engine	Individual owner California	Standard	1986-04-29	Valid
N6176X	Cessna 310R	Fixed-wing, multi-engine	Central Texas College Killeen, Texas	Standard	1986-04-24	Valid
N4546F	Cessna A185E	Fixed-wing, single engine	Individual owner Montana	Standard	1986-04-16	Valid
N12VM	Cessna 210M	Fixed-wing, single engine	S & R Air INC Asheville, North Carolina	Standard	1986-03-24	Valid
N29022	Cessna 210L	Fixed-wing, single engine	Unifly INC Lackawanna, New York	Standard	1986-03-05	Valid
N2531Q	Cessna A185E	Fixed-wing, single engine	Withheld at owner's request	Standard	1986-02-25	Valid
N18246	Beech F33A	Fixed-wing, single engine	Radial-Air Leasing INC Caro, Michigan	Standard	1986-02-19	Valid
N6810S	Beech 58	Fixed-wing, multi-engine	Usda-Aphis-Ppq Edinburg, Texas	Multiple	1986-02-19	Valid
N2631S	Cessna 310R	Fixed-wing, multi-engine	Individual owner Pennsylvania	Standard	1986-02-12	Valid
N10Y	Cessna 210L	Fixed-wing, single engine	Individual owner Texas	Standard	1986-01-16	Valid
N6504E	Cessna A185F	Fixed-wing, single engine	Individual owner Colorado	Standard	1986-01-10	Valid
N4950Z	Cessna U206G	Fixed-wing, single engine	Riverside Tractor INC Friendswood, Texas	Standard	1985-12-26	Valid
N714ZK	Cessna A185F	Fixed-wing, single engine	Individual owner Virginia	Standard	1985-12-10	Valid
N5986F	Cessna 210H	Fixed-wing, single engine	Individual owner Idaho	Standard	1985-11-22	Valid
N2080S	Beech V35	Fixed-wing, single engine	Individual owner Massachusetts	Standard	1985-11-15	Valid
N79080	Cessna A188B	Fixed-wing, single engine	Co-owned owner Montana	Restricted	1985-11-15	Valid
N321MM	Cessna A185F	Fixed-wing, single engine	Co-owned owner Minnesota	Standard	1985-11-12	Valid
N185RD	Cessna A185F	Fixed-wing, single engine	Co-owned owner Alaska	Standard	1985-11-07	Valid
N4448R	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1985-10-31	Valid
N888JR	Beech A36	Fixed-wing, single engine	Jones & Weaver PC Wheatland, Wyoming	Standard	1985-09-17	Valid
N731EQ	Cessna A188B	Fixed-wing, single engine	United States Department of Agriculture Edinburg, Texas	Restricted	1985-09-07	Valid
N1848Q	Cessna A185F	Fixed-wing, single engine	Individual owner Washington	Standard	1985-09-03	Valid
N2842W	Beech V35B	Fixed-wing, single engine	Individual owner Texas	Standard	1985-08-26	Valid
N735AX	Cessna A185F	Fixed-wing, single engine	State of North Carolina Raleigh, North Carolina	Standard	1985-08-19	Valid
N735DN	Cessna A185F	Fixed-wing, single engine	State of North Carolina Raleigh, North Carolina	Standard	1985-08-19	Valid
N735EK	Cessna A185F	Fixed-wing, single engine	State of North Carolina Raleigh, North Carolina	Standard	1985-08-19	Valid
N5840S	Beech S35	Fixed-wing, single engine	Bergstrom Aircraft INC Pasco, Washington	Standard	1985-08-16	Valid
N7848R	Beech V35A	Fixed-wing, single engine	Individual owner California	Standard	1985-08-08	Valid
N735QP	Cessna U206G	Fixed-wing, single engine	Individual owner Alaska	Standard	1985-07-30	Valid
N36BN	Beech A36	Fixed-wing, single engine	Solar Symmetry INC Southold, New York	Standard	1985-07-29	Valid
N90WS	Cessna 210M	Fixed-wing, single engine	Individual owner Maryland	Standard	1985-07-18	Valid
N543DG	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1985-07-11	Valid
N2065Q	Beech A36	Fixed-wing, single engine	Individual owner New York	Standard	1985-07-09	Valid
N123TM	Cessna U206F	Fixed-wing, single engine	Jaars INC Waxhaw, North Carolina	Experimental	1985-07-08	Valid
N884T	Beech S35	Fixed-wing, single engine	Perryton Motor CO INC Perryton, Texas	Special flight permit	1985-06-05	Valid
N18LL	Beech A36	Fixed-wing, single engine	Piping Technology Consultants INC Monee, Illinois	Standard	1985-05-29	Valid
N4456W	Beech A36	Fixed-wing, single engine	Metal Finishing CO INC Wichita, Kansas	Standard	1985-05-20	Valid
N9910M	Cessna 210M	Fixed-wing, single engine	Individual owner Minnesota	Standard	1985-05-17	Valid
N2038V	Beech A36	Fixed-wing, single engine	Individual owner Arizona	Standard	1985-04-29	Valid
N2383Y	Cessna 210E	Fixed-wing, single engine	Individual owner Washington	Standard	1985-04-08	Valid
N3962G	Cessna TU206C	Fixed-wing, single engine	Joe Sanchez Farms INC Walnut Grove, California	Standard	1985-02-22	Valid
N2038U	Beech V35B	Fixed-wing, single engine	World Aero Space LTD Henderson, North Carolina	Standard	1985-02-08	Valid
N590PM	Beech V35A	Fixed-wing, single engine	Individual owner Kansas	Standard	1985-02-05	Valid
N1025W	Beech V35B	Fixed-wing, single engine	Individual owner Wisconsin	Standard	1985-01-08	Valid
N3906Y	Cessna 210D	Fixed-wing, single engine	Individual owner Wyoming	Standard	1985-01-08	Valid
N2160S	Cessna 210L	Fixed-wing, single engine	Individual owner New Jersey	Standard	1984-12-17	Valid
N6276V	Beech V35A	Fixed-wing, single engine	Individual owner Florida	Standard	1984-10-29	Valid
N32MB	Beech 36	Fixed-wing, single engine	Marin Airmen INC Mill Valley, California	Standard	1984-10-19	Valid
N626S	Beech V35	Fixed-wing, single engine	Individual owner Texas	Standard	1984-10-15	Valid
N20444	Beech F33A	Fixed-wing, single engine	Individual owner Oregon	Standard	1984-09-24	Valid
N834TM	Beech S35	Fixed-wing, single engine	Individual owner Washington	Standard	1984-09-05	Valid
N6559	Beech F33A	Fixed-wing, single engine	Individual owner Texas	Standard	1984-09-04	Valid
N18500	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1984-08-06	Valid
N2267A	Beech V35A	Fixed-wing, single engine	Individual owner South Carolina	Standard	1984-08-06	Valid
N58235	Cessna A188	Fixed-wing, single engine	Individual owner Texas	Restricted	1984-07-25	Valid
N714NK	Cessna A185F	Fixed-wing, single engine	State of Alaska Anchorage, Alaska	Standard	1984-07-19	Valid
N9264R	Cessna A188B	Fixed-wing, single engine	Air Dakota Flite INC Hettinger, North Dakota	Restricted	1984-06-22	Valid
N22ED	Beech E35	Fixed-wing, single engine	Co-owned owner California	Standard	1984-05-31	Valid
N7346R	Beech A36	Fixed-wing, single engine	Seagull Flying Club INC San Jose, California	Standard	1984-05-31	Valid
N4648F	Cessna P206A	Fixed-wing, single engine	Simmons Daniel A Huntsville, Alabama	Standard	1984-05-10	Valid
N4726Q	Cessna A188B	Fixed-wing, single engine	Becker Flying Service INC Hartington, Nebraska	Restricted	1984-04-17	Valid
N70248	Cessna A185E	Fixed-wing, single engine	L C Hanson CO INC Clancy, Montana	Restricted	1984-02-13	Valid
N2100E	Beech A36	Fixed-wing, single engine	Individual owner Indiana	Standard	1984-02-10	Valid
N81JB	Beech V35A	Fixed-wing, single engine	Individual owner California	Standard	1984-02-10	Valid
N5082E	Cessna A185F	Fixed-wing, single engine	Individual owner Montana	Standard	1984-01-21	Valid
N9641Z	Cessna U206G	Fixed-wing, single engine	Individual owner Washington	Standard	1984-01-21	Valid
N30CA	Beech F33A	Fixed-wing, single engine	State of California Department of Transportation Sacramento, California	Standard	1984-01-04	Valid
N9561Q	Beech V35	Fixed-wing, single engine	Individual owner Michigan	Standard	1983-12-23	Valid
N448L	Beech A36	Fixed-wing, single engine	Aircraft Management CORP Wilmington, Delaware	Standard	1983-10-24	Valid
N6182X	Beech A36	Fixed-wing, single engine	Individual owner New York	Standard	1983-09-29	Valid
N1339G	Cessna 310R	Fixed-wing, multi-engine	Lyon Aviation INC Pittsfield, Massachusetts	Standard	1983-09-28	Valid

Source: FAA Civil Aviation Registry, Releasable Aircraft Database (the engine reference table and each aircraft's engine code), October 8, 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