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
N6MZ	Beech F33A	Fixed-wing, single engine	Individual owner West Virginia	Standard	1996-06-17	Valid
N511SP	Beech A36	Fixed-wing, single engine	Individual owner Kentucky	Standard	1996-06-10	Valid
N9687H	Cessna A185F	Fixed-wing, single engine	Individual owner Oregon	Standard	1996-05-31	Valid
N7331U	Cessna 207A	Fixed-wing, single engine	Bristol Bay Air Service INC Dillingham, Alaska	Standard	1996-05-29	Valid
N4074S	Beech F33A	Fixed-wing, single engine	Individual owner Minnesota	Standard	1996-05-28	Valid
N67JA	Cessna U206G	Fixed-wing, single engine	Jaars INC Waxhaw, North Carolina	Standard	1996-05-22	Valid
N12AS	Cessna A185F	Fixed-wing, single engine	Individual owner California	Multiple	1996-05-20	Valid
N6JV	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1996-05-20	Valid
N185P	Cessna A185F	Fixed-wing, single engine	Aerial Associates LTD Delano, Minnesota	Standard	1996-05-08	Valid
N14AR	Beech F33A	Fixed-wing, single engine	Individual owner Alabama	Standard	1996-05-07	Valid
N165HP	Beech A36	Fixed-wing, single engine	Co-owned owner Texas	Standard	1996-05-01	Valid
N5416R	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1996-04-23	Valid
N22CV	Cessna 210L	Fixed-wing, single engine	Individual owner Florida	Standard	1996-04-12	Valid
N8610Q	Beech S35	Fixed-wing, single engine	Individual owner Illinois	Standard	1996-03-28	Valid
N77DA	Beech F33A	Fixed-wing, single engine	Duncan Aviation INC Lincoln, Nebraska	Standard	1996-03-12	Valid
N206ML	Cessna U206G	Fixed-wing, single engine	Co-owned owner Minnesota	Standard	1996-03-11	Valid
N221JE	Cessna U206F	Fixed-wing, single engine	Individual owner Alaska	Multiple	1996-03-07	Valid
N99SB	Beech A36	Fixed-wing, single engine	Bonanza Service LTD CO Bethany, Oklahoma	Standard	1996-03-04	Valid
N9721Z	Cessna U206G	Fixed-wing, single engine	Rwr INC Wasilla, Alaska	Standard	1996-03-02	Valid
N731PH	Cessna A188B	Fixed-wing, single engine	Individual owner Texas	Restricted	1996-02-29	Valid
N3731Y	Cessna 210D	Fixed-wing, single engine	Individual owner Colorado	Standard	1996-02-28	Valid
N79MM	Beech E33C	Fixed-wing, single engine	Individual owner Texas	Standard	1996-02-28	Valid
N3417G	Cessna 310R	Fixed-wing, multi-engine	Demark Aviation INC Wilmington, Delaware	Standard	1996-01-29	Valid
N110CC	Beech V35	Fixed-wing, single engine	Intermountain Aero INC Salt Lake City, Utah	Standard	1996-01-05	Valid
N666SB	Cessna A185F	Fixed-wing, single engine	Co-owned owner California	Standard	1995-12-20	Valid
N5711V	Beech 95-C55	Fixed-wing, multi-engine	Individual owner Nevada	Standard	1995-12-06	Valid
N7745R	Beech 36	Fixed-wing, single engine	Individual owner California	Standard	1995-12-06	Valid
N2785J	Cessna A185E	Fixed-wing, single engine	Individual owner Utah	Multiple	1995-12-01	Valid
N3791Y	Cessna 210D	Fixed-wing, single engine	Satanta Flying Service INC Satanta, Kansas	Standard	1995-11-29	Valid
N1JJ	Bellanca 17-30A	Fixed-wing, single engine	Individual owner Ohio	Standard	1995-11-06	Valid
N9555G	Cessna A188B	Fixed-wing, single engine	Individual owner Alabama	Restricted	1995-10-26	Valid
N5500F	Beech F33A	Fixed-wing, single engine	Individual owner Colorado	Standard	1995-10-25	Valid
N4753F	Cessna P206B	Fixed-wing, single engine	Individual owner Tennessee	Standard	1995-10-19	Valid
N145PL	Cessna U206G	Fixed-wing, single engine	State of Alaska Anchorage, Alaska	Standard	1995-10-18	Valid
N4889J	Beech V35	Fixed-wing, single engine	Withheld at owner's request	Standard	1995-10-17	Valid
N5071C	Beech B35	Fixed-wing, single engine	Co-owned owner Missouri	Standard	1995-10-16	Valid
N3805Y	Cessna 210D	Fixed-wing, single engine	Macys Flying Service INC Tulelake, California	Standard	1995-10-13	Valid
N61273	Cessna U206F	Fixed-wing, single engine	Wrangell Mountain Air INC Palmer, Alaska	Standard	1995-09-30	Valid
N7372H	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Standard	1995-09-30	Valid
N70403	Cessna A188B	Fixed-wing, single engine	Individual owner Alabama	Restricted	1995-09-29	Valid
N185SW	Cessna A185F	Fixed-wing, single engine	K and S Aviation INC Pagosa Springs, Colorado	Standard	1995-09-21	Valid
N3995A	Cessna 310R	Fixed-wing, multi-engine	Co-owned owner West Virginia	Standard	1995-09-21	Valid
N23639	Beech A36	Fixed-wing, single engine	Teleprint INC Rydal, Pennsylvania	Standard	1995-09-20	Valid
N4572F	Cessna A185E	Fixed-wing, single engine	Individual owner Florida	Standard	1995-09-16	Valid
N3ZE	Navion NAVION H	Fixed-wing, single engine	Zephyr Enterprises INC Wilmington, Delaware	Standard	1995-09-13	Valid
N2051W	Beech A36	Fixed-wing, single engine	Individual owner New Jersey	Standard	1995-08-29	Valid
N375HW	Cessna 210D	Fixed-wing, single engine	Individual owner Arkansas	Standard	1995-08-29	Valid
N71LM	Beech F33A	Fixed-wing, single engine	Co-owned owner New Hampshire	Standard	1995-08-25	Valid
N148PR	Beech V35	Fixed-wing, single engine	Co-owned owner California	Standard	1995-08-22	Valid
N91JP	Beech V35B	Fixed-wing, single engine	Individual owner Michigan	Standard	1995-08-21	Valid
N1867F	Cessna 210F	Fixed-wing, single engine	Icarus Aviators LLC Canon City, Colorado	Standard	1995-08-14	Valid
N301MC	Cessna A185F	Fixed-wing, single engine	Individual owner Colorado	Standard	1995-08-05	Valid
N4130S	Beech 58	Fixed-wing, multi-engine	Individual owner Pennsylvania	Standard	1995-08-03	Valid
N72117	Cessna U206D	Fixed-wing, single engine	Individual owner Montana	Multiple	1995-07-28	Valid
N1562B	Beech F33A	Fixed-wing, single engine	Co-owned owner California	Standard	1995-07-21	Valid
N731QC	Cessna A188B	Fixed-wing, single engine	Tim Whitfield Aviation Fairfield, North Carolina	Restricted	1995-06-30	Valid
N4909U	Cessna 210E	Fixed-wing, single engine	Individual owner Florida	Standard	1995-06-26	Valid
N18456	Beech A36	Fixed-wing, single engine	Co-owned owner California	Standard	1995-06-21	Valid
N703T	Beech V35B	Fixed-wing, single engine	Individual owner Texas	Standard	1995-06-20	Valid
N5821F	Cessna 210G	Fixed-wing, single engine	Flite Five INC Kiowa, Kansas	Standard	1995-06-16	Valid
N5825K	Beech S35	Fixed-wing, single engine	Bonanza Over Miami INC Coral Gables, Florida	Standard	1995-06-14	Valid
N9204G	Cessna A188B	Fixed-wing, single engine	Individual owner Montana	Restricted	1995-06-05	Valid
N8191R	Beech V35B	Fixed-wing, single engine	M B Duncan INC Bakersfield, California	Standard	1995-06-01	Valid
N1785A	Beech E33A	Fixed-wing, single engine	Individual owner Georgia	Standard	1995-05-31	Valid
N72306	Cessna U206D	Fixed-wing, single engine	Usda Aphis Ppq Edinburg, Texas	Multiple	1995-05-24	Valid
N343U	Beech 35-C33A	Fixed-wing, single engine	Individual owner Oregon	Standard	1995-05-18	Valid
N25VB	Beech V35B	Fixed-wing, single engine	Otto Aircraft Sales INC Sarasota, Florida	Standard	1995-05-16	Reports overdue
N28057	Bellanca 17-30A	Fixed-wing, single engine	Co-owned owner California	Standard	1995-05-16	Valid
N1848R	Cessna A185F	Fixed-wing, single engine	Individual owner Alaska	Restricted	1995-05-04	Valid
N274HS	Beech V35B	Fixed-wing, single engine	Individual owner Oregon	Standard	1995-05-02	Valid
N1CK	Beech 35-C33A	Fixed-wing, single engine	Individual owner Illinois	Standard	1995-04-24	Valid
N4272S	Beech V35B	Fixed-wing, single engine	Individual owner New York	Standard	1995-04-17	Valid
N4455Q	Cessna A188B	Fixed-wing, single engine	Individual owner Kansas	Restricted	1995-04-14	Valid
N119AB	Beech 95-C55	Fixed-wing, multi-engine	Safford Aviation Service INC Coolidge, Arizona	Standard	1995-04-03	Valid
N81631	Cessna U206G	Fixed-wing, single engine	Individual owner Alaska	Standard	1995-03-30	Valid
N734PP	Cessna U206G	Fixed-wing, single engine	Individual owner Alaska	Standard	1995-03-29	Valid
N6709V	Bellanca 17-30A	Fixed-wing, single engine	Co-owned owner Oklahoma	Standard	1995-03-27	Valid
N5713K	Beech S35	Fixed-wing, single engine	Jennings James H Clovis, New Mexico	Standard	1995-03-09	Valid
N1459M	Cessna U206E	Fixed-wing, single engine	K and L Aviation Incorporated Wilmington, Delaware	Standard	1995-02-17	Valid
N11C	Cessna A185F	Fixed-wing, single engine	Individual owner California	Standard	1995-02-15	Valid
N9540G	Cessna A188B	Fixed-wing, single engine	Individual owner Montana	Restricted	1995-02-11	Valid
N222NW	Beech F33A	Fixed-wing, single engine	Individual owner California	Standard	1995-02-06	Valid
N4677Q	Cessna 210L	Fixed-wing, single engine	Individual owner North Dakota	Standard	1995-02-06	Valid
N1647Z	Cessna 185A	Fixed-wing, single engine	Individual owner Alaska	Multiple	1995-02-02	Valid
N9470G	Cessna U206E	Fixed-wing, single engine	Individual owner California	Standard	1995-01-24	Valid
N15DS	Cessna 320D	Fixed-wing, multi-engine	All Attitude Aviation INC Edgewater, Florida	Standard	1995-01-18	Valid
N3693A	Beech S35	Fixed-wing, single engine	C and F Enterprise L L C Milford, Michigan	Standard	1995-01-18	Valid
N4433R	Cessna A185F	Fixed-wing, single engine	Wtf Partnership Anchorage, Alaska	Multiple	1995-01-17	Valid
N863S	Beech V35A	Fixed-wing, single engine	Individual owner Tennessee	Standard	1995-01-17	Valid
N149G	Beech V35	Fixed-wing, single engine	Metro Flyers LTD N Richland Hills, Texas	Standard	1995-01-12	Valid
N4374M	Beech A36	Fixed-wing, single engine	Individual owner Texas	Standard	1995-01-05	Valid
N3682Z	Beech 58	Fixed-wing, multi-engine	Iliamna Air Taxi INC Iliamna, Alaska	Standard	1994-12-29	Valid
N51CM	Cessna 210L	Fixed-wing, single engine	Co-owned owner Tennessee	Standard	1994-12-28	Valid
N758C	Beech 58	Fixed-wing, multi-engine	G Daniel Evans P C Birmingham, Alabama	Standard	1994-12-14	Valid
N732NS	Cessna U206G	Fixed-wing, single engine	Civil Air Patrol INC Maxwell Afb, Alabama	Standard	1994-11-17	Valid
N1708R	Cessna A185F	Fixed-wing, single engine	Co-owned owner California	Standard	1994-11-15	Valid
N4720V	Bellanca 17-30	Fixed-wing, single engine	Individual owner Connecticut	Standard	1994-11-08	Valid
N8243R	Bellanca 17-30A	Fixed-wing, single engine	Co-owned owner Colorado	Standard	1994-10-20	Valid
N181CB	Beech V35B	Fixed-wing, single engine	Individual owner Florida	Standard	1994-09-27	Valid
N3939G	Cessna TU206C	Fixed-wing, single engine	Three Niner Gulf L L C Denver, Colorado	Standard	1994-09-27	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