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
N8401Q	Cessna A185F	Fixed-wing, single engine	Individual owner Ohio	Standard	1990-01-30	Valid
N68AP	Beech V35A	Fixed-wing, single engine	Abecca Corporation Jackson, Michigan	Standard	1990-01-26	Valid
N5685J	Cessna A188A	Fixed-wing, single engine	Anderson Aerial Spraying Service Canby, Minnesota	Multiple	1990-01-25	Valid
N8093R	Beech V35A	Fixed-wing, single engine	Individual owner Washington	Standard	1990-01-19	Valid
N5614R	Beech F33A	Fixed-wing, single engine	Co-owned owner Pennsylvania	Standard	1990-01-10	Valid
N87DB	Beech V35	Fixed-wing, single engine	Blanchat Manufacturing INC Harper, Kansas	Standard	1990-01-08	Valid
N525X	Cessna 206	Fixed-wing, single engine	Individual owner Michigan	Standard	1989-12-20	Valid
N8383Q	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1989-12-05	Valid
N80499	Cessna A185F	Fixed-wing, single engine	Srf Waterloo, Iowa	Standard	1989-11-06	Valid
N71900	Cessna U206C	Fixed-wing, single engine	Individual owner Idaho	Standard	1989-11-02	Valid
N21LP	Beech 58	Fixed-wing, multi-engine	LP Aviation INC Wilmington, Delaware	Standard	1989-10-24	Valid
N9240R	Cessna A188B	Fixed-wing, single engine	Air Dakota Flite Hettinger, North Dakota	Restricted	1989-10-12	Valid
N50MB	Cessna U206G	Fixed-wing, single engine	Civil Air Patrol INC Maxwell Afb, Alabama	Standard	1989-10-04	Valid
N9128Q	Beech A36	Fixed-wing, single engine	Withheld at owner's request	Standard	1989-09-11	Valid
N5428U	Cessna U206G	Fixed-wing, single engine	Cordova Air Service INC Cordova, Alaska	Standard	1989-08-14	Valid
N1SB	Cessna A185F	Fixed-wing, single engine	Individual owner Kansas	Standard	1989-08-10	Valid
N685TB	Beech A36	Fixed-wing, single engine	Yankee Flyers INC Mount Vernon, Iowa	Standard	1989-08-03	Valid
N2272X	Cessna U206E	Fixed-wing, single engine	Southern Seaplane INC Belle Chasse, Louisiana	Standard	1989-07-31	Valid
N5864F	Cessna 210G	Fixed-wing, single engine	Individual owner Wisconsin	Standard	1989-07-25	Valid
N9192Q	Beech A36	Fixed-wing, single engine	Monroe Aviation INC Verona, Pennsylvania	Standard	1989-07-24	Valid
N23578	Beech A36	Fixed-wing, single engine	Green Law Aviation INC Culpeper, Virginia	Standard	1989-07-20	Valid
N413LB	Cessna A185F	Fixed-wing, single engine	Oficinas de Carolina INC San Juan, Puerto Rico	Standard	1989-06-28	Valid
N93913	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1989-06-26	Valid
N8MP	Beech V35	Fixed-wing, single engine	Foreman Thomas H Orange, Texas	Standard	1989-06-23	Valid
N409PD	Beech F33A	Fixed-wing, single engine	Iowa Great Lakes Flyers INC Cheyenne, Wyoming	Standard	1989-06-15	Valid
N18351	Beech 58	Fixed-wing, multi-engine	Iowa Great Lakes Flyers LTD Cheyenne, Wyoming	Standard	1989-06-14	Valid
N206US	Cessna U206F	Fixed-wing, single engine	Co-owned owner Idaho	Standard	1989-06-01	Valid
N731PM	Cessna A188B	Fixed-wing, single engine	Air AG INC Tarboro, North Carolina	Restricted	1989-05-22	Valid
N102JM	Beech V35B	Fixed-wing, single engine	Individual owner Ohio	Standard	1989-05-19	Valid
N555CD	Cessna A185F	Fixed-wing, single engine	Individual owner Pennsylvania	Standard	1989-05-16	Valid
N721EB	Beech 35-C33A	Fixed-wing, single engine	Biggs Aircraft INC Wellston, Oklahoma	Standard	1989-05-02	Valid
N1764X	Cessna 210L	Fixed-wing, single engine	Individual owner Texas	Standard	1989-05-01	Valid
N6035B	Beech V35B	Fixed-wing, single engine	Montgomery Aviation Corporation Montgomery, Alabama	Standard	1989-04-19	Valid
N72MD	Beech A36	Fixed-wing, single engine	Individual owner New York	Standard	1989-04-17	Valid
N3367	Beech 95-C55	Fixed-wing, multi-engine	Klaasmeyer Construction CO Conway, Arkansas	Standard	1989-04-06	Valid
N1195T	Beech A36	Fixed-wing, single engine	Individual owner Alabama	Standard	1989-03-23	Valid
N5834K	Beech S35	Fixed-wing, single engine	Individual owner Texas	Standard	1989-03-10	Valid
N84SR	Beech F33A	Fixed-wing, single engine	Sunnydaze LTD Northville, Michigan	Standard	1989-03-01	Valid
N7573Q	Cessna A185F	Fixed-wing, single engine	Individual owner Colorado	Standard	1989-02-16	Valid
N10HG	Cessna 210L	Fixed-wing, single engine	Individual owner Texas	Standard	1989-02-07	Valid
N80629	Cessna A185F	Fixed-wing, single engine	Co-owned owner Washington	Standard	1989-02-07	Valid
N2036S	Cessna 210L	Fixed-wing, single engine	Lissie Flying Service Lissie, Texas	Standard	1989-01-13	Valid
N55K	Beech A36	Fixed-wing, single engine	Mbi Indn Hbr Bch, Florida	Standard	1988-12-14	Valid
N2103S	Cessna 210L	Fixed-wing, single engine	San Diego Flight CORP San Diego, California	Standard	1988-12-12	Valid
N302W	Beech A36	Fixed-wing, single engine	Individual owner South Carolina	Standard	1988-11-07	Valid
N8167Q	Cessna U206F	Fixed-wing, single engine	Cedar Pine Construction INC Sturgis, South Dakota	Standard	1988-11-07	Valid
N11HT	Beech V35	Fixed-wing, single engine	Jet X Leasing INC Johnson, Kansas	Standard	1988-11-01	Valid
N1UZ	Beech S35	Fixed-wing, single engine	Jet X Leasing INC Johnson, Kansas	Standard	1988-10-25	Valid
N5873F	Cessna 210G	Fixed-wing, single engine	Individual owner California	Standard	1988-10-14	Valid
N26UR	Beech F33A	Fixed-wing, single engine	Dartswift INC Philadelphia, Pennsylvania	Standard	1988-09-21	Valid
N4960U	Cessna 210E	Fixed-wing, single engine	Individual owner Arkansas	Standard	1988-09-09	Valid
N9673E	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Ohio	Standard	1988-08-18	Valid
N8395N	Beech V35A	Fixed-wing, single engine	Co-owned owner Indiana	Standard	1988-08-08	Valid
N4405A	Beech V35B	Fixed-wing, single engine	Individual owner Washington	Standard	1988-08-04	Valid
N8290R	Bellanca 17-30A	Fixed-wing, single engine	Individual owner California	Standard	1988-07-23	Valid
N991D	Beech 95-C55	Fixed-wing, multi-engine	Individual owner Montana	Standard	1988-07-19	Valid
N99DS	Cessna 210L	Fixed-wing, single engine	Individual owner Connecticut	Standard	1988-07-14	Valid
N18361	Beech 58	Fixed-wing, multi-engine	Individual owner Vermont	Standard	1988-06-29	Valid
N9709E	Bellanca 17-30A	Fixed-wing, single engine	Viking Flying Association INC Scottsboro, Alabama	Standard	1988-06-21	Valid
N33JH	Cessna A185F	Fixed-wing, single engine	Co-owned owner Alaska	Standard	1988-05-18	Valid
N9473M	Cessna 210K	Fixed-wing, single engine	Co-owned owner Michigan	Standard	1988-05-11	Valid
N9935R	Cessna U206G	Fixed-wing, single engine	Usda Aphis Ppq Edinburg, Texas	Multiple	1988-05-09	Valid
N2781D	Cessna 185	Fixed-wing, single engine	Fejes Guide Service LTD Anchorage, Alaska	Standard	1988-05-02	Valid
N6034R	Beech A36	Fixed-wing, single engine	Individual owner Texas	Standard	1988-05-02	Valid
N8WL	Cessna U206G	Fixed-wing, single engine	South Carolina Department of Natural Resources Columbia, South Carolina	Standard	1988-05-02	Valid
N1286F	Cessna A185F	Fixed-wing, single engine	Taylor Aviation INC Mazama, Washington	Standard	1988-04-20	Valid
N61301	Cessna A185F	Fixed-wing, single engine	Southern Seaplane INC Belle Chasse, Louisiana	Standard	1988-04-20	Valid
N411ML	Beech A36	Fixed-wing, single engine	Individual owner Florida	Standard	1988-04-19	Valid
N36PW	Beech A36	Fixed-wing, single engine	Individual owner New Mexico	Standard	1988-03-28	Valid
N727FK	Cessna 210G	Fixed-wing, single engine	Individual owner Washington	Standard	1988-02-08	Valid
N2141F	Cessna U206	Fixed-wing, single engine	Individual owner Alaska	Restricted	1988-01-21	Valid
N1943M	Cessna 210M	Fixed-wing, single engine	Individual owner New Jersey	Standard	1988-01-14	Valid
N1977U	Cessna A185E	Fixed-wing, single engine	Individual owner Alaska	Standard	1987-12-15	Valid
N25RH	Beech F33A	Fixed-wing, single engine	Poseidon Transport INC Watertown, New York	Standard	1987-12-11	Valid
N8917M	Beech S35	Fixed-wing, single engine	Aero Flite del INC Felton, Delaware	Standard	1987-12-04	Valid
N4896J	Beech V35	Fixed-wing, single engine	Co-owned owner Colorado	Standard	1987-12-02	Valid
N8621Q	Beech S35	Fixed-wing, single engine	Individual owner California	Standard	1987-12-02	Valid
N1227F	Cessna A185F	Fixed-wing, single engine	Peterson Investments INC Polson, Montana	Standard	1987-12-01	Valid
N605NR	Cessna A185F	Fixed-wing, single engine	State of Minnesota Grand Rapids, Minnesota	Standard	1987-11-24	Valid
N4950R	Cessna U206G	Fixed-wing, single engine	Civil Air Patrol INC Natl Hdqtrs Maxwell Afb, Alabama	Standard	1987-10-29	Valid
N6605V	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Delaware	Standard	1987-10-07	Valid
N7803R	Beech D55	Fixed-wing, multi-engine	Rick Franklin CORP Lebanon, Oregon	Standard	1987-09-30	Valid
N91159	Navion NAVION A	Fixed-wing, single engine	Individual owner Idaho	Standard	1987-09-30	Valid
N100SP	Beech V35B	Fixed-wing, single engine	Individual owner California	Standard	1987-09-18	Valid
N9YR	Beech E-55	Fixed-wing, multi-engine	Individual owner Colorado	Standard	1987-08-25	Valid
N517PY	Beech F33A	Fixed-wing, single engine	Individual owner North Carolina	Standard	1987-08-19	Valid
N5827F	Cessna 210G	Fixed-wing, single engine	Individual owner Massachusetts	Standard	1987-08-17	Valid
N8795Z	Cessna P206D	Fixed-wing, single engine	Individual owner Arizona	Standard	1987-08-11	Valid
N9145Q	Beech E-55	Fixed-wing, multi-engine	Individual owner Ohio	Standard	1987-08-10	Valid
N9261G	Cessna A188B	Fixed-wing, single engine	Individual owner Alabama	Restricted	1987-08-08	Valid
N19RF	Beech A36	Fixed-wing, single engine	Lynn Air Flying Club INC Woodinville, Washington	Standard	1987-08-03	Valid
N7605U	Cessna 207A	Fixed-wing, single engine	Ryan Air INC Anchorage, Alaska	Standard	1987-07-30	Valid
N8570Q	Cessna U206F	Fixed-wing, single engine	Two O Six INC Fort Myers, Florida	Standard	1987-07-27	Valid
N53083	Cessna A185F	Fixed-wing, single engine	Clearwater Potlatch Timber Protect Orofino, Idaho	Multiple	1987-07-17	Valid
N4949R	Cessna A188B	Fixed-wing, single engine	Valley Flying Service INC Orleans, Nebraska	Restricted	1987-07-15	Valid
N24WK	Beech V35	Fixed-wing, single engine	Individual owner New York	Standard	1987-06-19	Valid
N732JT	Cessna 210L	Fixed-wing, single engine	Kittatinny Leasing CO INC Friendsville, Tennessee	Standard	1987-06-04	Valid
N9601E	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Texas	Standard	1987-06-04	Valid
N6137X	Cessna 310R	Fixed-wing, multi-engine	Moyer Aviation INC Ulysses, Kansas	Standard	1987-06-02	Valid
N4972Q	Cessna A185F	Fixed-wing, single engine	Individual owner Tennessee	Standard	1987-05-26	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