Engines · two-cycle piston · data as of October 5, 2026

Rotax 503 series

449 aircraft on the U.S. register carry a Rotax 503 series engine, rated at about 52 horsepower. The Quad City Ultralight Acft Corp CHALLENGER II is the model most often fitted with it (8 aircraft). The aircraft carrying it were built between 1983 and 2025.

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 Rotax 503 series. FAA spelling: 503 SERIES.

Fitted to model families

Quad City Ultralight Acft Corp CHALLENGER II8Quicksilver SPORT5Quad City Ultralights CHALLENGER II4Quicksilver GT-4004Quicksilver SPRINT II4Air Creation GTE3Air Creation TWIN3Buckeye DREAM MACHINE3Buckeye Industries DREAM MACHINE3North Wing APACHE3Pipistrel TAURUS3Powrachute Corp SKY RASCAL3

Quad City Ultralight Acft Corp CHALLENGER II · Quicksilver SPORT · Quad City Ultralights CHALLENGER II · Quicksilver GT-400 · Quicksilver SPRINT II · Air Creation GTE · Air Creation TWIN · Buckeye DREAM MACHINE · Buckeye Industries DREAM MACHINE · North Wing APACHE

Where they are owner's state

California29Florida28Texas22Indiana20Illinois20Wisconsin17Oklahoma15North Carolina15Ohio14Arizona14

Kind of aircraft

Piston singles321 (71%)Weight-shift and powered parachutes108 (24%)Gyroplanes9 (2%)Helicopters6 (1%)Gliders5 (1%)

When the aircraft were built by decade

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

Fitted to

Quad City Ultralight Acft Corp CHALLENGER II 8 with this engine series
Quicksilver SPORT 5 with this engine series
Quad City Ultralights CHALLENGER II 4 with this engine series
Quicksilver GT-400 4 with this engine series
Quicksilver SPRINT II 4 with this engine series
Air Creation GTE 3 with this engine series
Air Creation TWIN 3 with this engine series
Buckeye DREAM MACHINE 3 with this engine series

Where they are

California 29 of these aircraft
Florida 28 of these aircraft
Texas 22 of these aircraft
Indiana 20 of these aircraft
Illinois 20 of these aircraft

Biggest operators

Tsi Holdco INC 1 of these aircraft

Analytics

These connections as data: /graph/engine/rotax-503-series.json · about the eFlight graph.

Aircraft newest certificates first · 449

Tail no.	Maker and model	Group	Owner and base	Certificate	Registered	Status
N503AG	Perdue Frederick V LW3	Gyroplane	Individual owner Florida	Experimental	2019-01-15	Valid
N1717P	Aerotrike SAFARI	Weight-shift control	Individual owner Indiana	Experimental	2019-01-08	Valid
N378RA	Autrey David M MAXAIR DRIFTER XP503	Fixed-wing, single engine	Individual owner Texas	Experimental	2018-12-10	Valid
N587JG	Cgs Aviation HAWK CLASSIC II	Fixed-wing, single engine	Individual owner Arizona	Experimental	2018-12-10	Valid
N1008J	Sport Flight Aviation MAGNUM	Fixed-wing, single engine	Individual owner California	Experimental	2018-11-06	Valid
N1624Z	Eipper Formance Inc MXII	Fixed-wing, single engine	Individual owner South Carolina	Experimental	2018-10-26	Valid
N31502	North Wing APACHE	Weight-shift control	Individual owner New Mexico	Experimental	2018-10-02	Valid
N1302A	Jerry L Sukeforth /Carroll E LIL AIRBOSS	Powered parachute	Individual owner New Hampshire	Experimental	2018-09-25	Valid
N241KF	Smith Richard L S-14	Fixed-wing, single engine	Individual owner Ohio	Experimental	2018-09-20	Valid
N10659	Christine Daniel P QUICKSILVER MXL II	Fixed-wing, single engine	Individual owner Illinois	Experimental	2018-09-18	Valid
N996LT	Turner Lloyd D MINI MAX 1600	Fixed-wing, single engine	Individual owner Indiana	Experimental	2018-08-24	Valid
N4476G	Rans S-14	Fixed-wing, single engine	Individual owner California	Experimental	2018-08-23	Valid
N357JB	John A Bubel SKY STAR II	Fixed-wing, single engine	Individual owner Texas	Experimental	2018-07-23	Valid
N12QC	Goulet David L CHALLENGER II	Fixed-wing, single engine	Individual owner Iowa	Experimental	2018-07-17	Valid
N7256R	Mark Wilke CHALLENGER II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2018-07-16	Valid
N477BM	Chidley Philip D CHALLENGER II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2018-06-20	Valid
N921CW	Pegasus SUPER SPORT	Weight-shift control	Individual owner Indiana	Experimental	2018-05-23	Valid
N9297Z	Buckeye DREAM MACHINE	Powered parachute	Individual owner Kansas	Experimental	2018-05-15	Valid
N2640W	Pegasus QUANTUM 15	Weight-shift control	Individual owner California	Experimental	2018-04-20	Valid
N841JP	Pires Joe ULTRAWHITE	Gyroplane	Individual owner South Carolina	Experimental	2018-04-05	Valid
N9218P	Quad City Ultralights CHALLENGER II	Fixed-wing, single engine	Individual owner South Carolina	Experimental	2018-03-27	Valid
N5645C	Powrachute Llc SKY RASCAL	Powered parachute	Individual owner North Carolina	Experimental	2018-02-28	Valid
N36TJ	Pegasus QUANTUM 15	Weight-shift control	Individual owner Indiana	Experimental	2018-02-07	Valid
N53MD	West Michael J MX II SPRINT	Fixed-wing, single engine	Individual owner Florida	Experimental	2018-01-24	Valid
N155SE	Kane Robert W CHALLENGER I	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2018-01-09	Valid
N224WB	Quad City Ultralight CHALLENGER II	Fixed-wing, single engine	Individual owner North Carolina	Experimental	2017-12-18	Valid
N93802	Quicksilver MXL II	Fixed-wing, single engine	Individual owner Michigan	Experimental	2017-11-29	Valid
N54EF	Air Creation GTE	Weight-shift control	Individual owner Oklahoma	Experimental	2017-11-01	Valid
N27595	Kolb Co Inc TWINSTAR MARK II	Fixed-wing, single engine	Individual owner Indiana	Experimental	2017-09-28	Valid
N7725C	Burnett SKY RAIDER	Powered parachute	Individual owner Illinois	Experimental	2017-08-16	Valid
N372CH	Titan TORNADO II	Fixed-wing, single engine	Individual owner Maryland	Experimental	2017-07-05	Valid
N403SC	James A Vanek LIGHTNING	Rotorcraft	Individual owner Arizona	Experimental	2017-05-04	Valid
N9191Y	Sinnott Chuck CHALLENGER II	Fixed-wing, single engine	Co-owned owner Kansas	Experimental	2017-03-20	Valid
N200HL	Dave Leedom DAL01	Fixed-wing, single engine	Co-owned owner California	Experimental	2017-03-17	Valid
N2544C	Sexton Jerry T KOLB FIRESTAR	Fixed-wing, single engine	Individual owner Maryland	Experimental	2017-02-06	Valid
N155KL	Quad City Ultralights CHALLENGER 2	Fixed-wing, single engine	Individual owner Georgia	Experimental	2016-12-09	Valid
N4436A	Quad City Ultralight Corp CHALLENGER II CWS	Fixed-wing, single engine	Individual owner Texas	Experimental	2016-11-29	Valid
N919PS	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2016-11-22	Valid
N5162Y	Parascender 2P	Powered parachute	Individual owner Wisconsin	Experimental	2016-10-26	Valid
N75KL	Airborne REDLEG	Weight-shift control	Individual owner Texas	Experimental	2016-10-21	Valid
N8515Q	Smith Stewart M CHALLENGER II	Fixed-wing, single engine	Individual owner Tennessee	Experimental	2016-09-26	Valid
N957SN	Norton Trell DOMINATOR	Rotorcraft	Individual owner Georgia	Experimental	2016-08-29	Valid
N967AC	Anthony Cvetkovich CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2016-08-03	Valid
N75564	Airborne EDGE	Weight-shift control	Individual owner Colorado	Experimental	2016-07-21	Valid
N4353W	Earthstar THUNDER GULL J	Fixed-wing, single engine	Individual owner Washington	Experimental	2016-07-20	Valid
N622HS	Shields Travis L TRAVAIR SPECIAL	Fixed-wing, single engine	Individual owner Alabama	Experimental	2016-07-14	Valid
N2542Q	Burch Robert L FIRESTAR II	Fixed-wing, single engine	Individual owner North Carolina	Experimental	2016-02-23	Valid
N125J	Judah John C CHALLENGER II	Fixed-wing, single engine	Individual owner Missouri	Experimental	2016-02-10	Valid
N6085D	Carlson Aircraft SPARROW	Fixed-wing, single engine	Individual owner North Dakota	Experimental	2016-01-12	Valid
N2534H	Emslie Don HERCULES	Weight-shift control	Individual owner Ohio	Experimental	2015-12-15	Valid
N3760V	Buckeye DREAM MACHINE	Powered parachute	Individual owner New York	Experimental	2015-11-10	Valid
N962DW	Daniel J Walczynski CHALLENGER II	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2015-10-23	Valid
N315BT	Phantom Aeronautics PHANTOM X-1E	Fixed-wing, single engine	Individual owner Virginia	Experimental	2015-10-05	Valid
N371KD	Gardner Kenneth E KOLB FIRESTAR II	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2015-10-05	Valid
N3749V	Jones Bobby Eugene CH 2	Fixed-wing, single engine	Individual owner South Carolina	Experimental	2015-09-29	Valid
N75502	Hayes James C CHALLENGER II	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2015-09-28	Valid
N2069P	Rans S-17 STINGER	Fixed-wing, single engine	Individual owner Arizona	Experimental	2015-08-04	Valid
N143JC	Quad City CHALLENGER II	Fixed-wing, single engine	Individual owner Puerto Rico	Experimental	2015-07-08	Valid
N475DX	Pipistrel TAURUS	Electric airplane	Individual owner Tennessee	Light sport	2015-07-06	Valid
N2690E	Olson Terry CHALLENGER 1	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2015-06-10	Valid
N503JC	Cleary James COMMANDER	Gyroplane	Individual owner Louisiana	Experimental	2015-06-09	Valid
N8073T	Alliant Aviation Llc XT 503	Powered parachute	Individual owner Oklahoma	Experimental	2015-05-13	Valid
N548DA	Boes Lanny T CHALLENGER II	Fixed-wing, single engine	Individual owner Ohio	Experimental	2015-04-30	Valid
N503TY	Turnquist Arlen J FIRESTAR II	Fixed-wing, single engine	Individual owner Missouri	Experimental	2015-04-23	Valid
N35066	Air Creation TWIN	Weight-shift control	Individual owner Louisiana	Experimental	2015-03-13	Valid
N61197	Eipper Aircraft QUICKSILVER MXLII	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2015-02-26	Valid
N8035F	Harmenings HIGH FLYERS	Powered parachute	Individual owner Pennsylvania	Experimental	2015-02-23	Valid
N499JY	Jay A Nielsen/William E Ford KOLB/FIRESTAR	Fixed-wing, single engine	Individual owner Illinois	Experimental	2015-02-18	Valid
N486FC	Shappee Carl KOLB MARK III	Fixed-wing, single engine	Individual owner Florida	Experimental	2015-02-17	Valid
N50469	Conner CGS HAWK ARROW PLUS	Fixed-wing, single engine	Individual owner New York	Experimental	2015-02-02	Valid
N354CH	Burgener Gerald W CHLNGR 2PL CLP WING	Fixed-wing, single engine	Co-owned owner Pennsylvania	Experimental	2015-01-28	Valid
N503WW	Aeros SPYDER	Weight-shift control	Individual owner Florida	Experimental	2015-01-22	Valid
N754UU	Quicksilver MXL II SPORT	Fixed-wing, single engine	Co-owned owner Washington	Experimental	2014-12-15	Valid
N8101Y	Air Creation 503 - TWIN	Weight-shift control	Individual owner Arizona	Experimental	2014-12-08	Valid
N75102	Rans S12	Fixed-wing, single engine	Individual owner Illinois	Experimental	2014-11-13	Valid
N136RB	Offield Ronnie KOLB FIRESTAR	Fixed-wing, single engine	Individual owner Virginia	Experimental	2014-10-03	Valid
N75501	Craig Casey POWRACHUTE PC 2000	Powered parachute	Co-owned owner Nevada	Experimental	2014-08-25	Valid
N2521D	Camerer Carl E SKYRAIDER I	Fixed-wing, single engine	Individual owner Mississippi	Experimental	2014-08-22	Valid
N14CU	Ultralight Flight Inc PHANTOM I	Fixed-wing, single engine	Individual owner South Carolina	Experimental	2014-07-14	Valid
N607AA	Robert S Nelsen FLIGHTSTAR II	Fixed-wing, single engine	Individual owner New Hampshire	Experimental	2014-07-14	Valid
N144XP	Leveque Warren S FALCON XP	Fixed-wing, single engine	Individual owner Tennessee	Experimental	2014-06-24	Valid
N5618E	Blue Heron EXPRESS	Powered parachute	Individual owner Texas	Experimental	2014-06-09	Valid
N29TX	Cubberly Robert L RANS S-14	Fixed-wing, single engine	Individual owner Texas	Experimental	2014-06-03	Valid
N61708	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Oregon	Experimental	2014-05-19	Valid
N8059V	Phillips Donald Terry X1-E	Fixed-wing, single engine	Individual owner Florida	Experimental	2014-03-25	Valid
N75530	Howell Arthur G AEROTRICK SAFARI	Weight-shift control	Individual owner Idaho	Experimental	2014-02-28	Valid
N2726T	Quicksilver SPORT	Fixed-wing, single engine	Individual owner California	Experimental	2014-02-25	Valid
N9257T	Antares Usa Corp M33A	Weight-shift control	Individual owner Massachusetts	Experimental	2014-02-12	Valid
N831L	Phantom X-1	Fixed-wing, single engine	Individual owner South Carolina	Experimental	2014-02-10	Valid
N506NB	Bowen C Bruce RIDGE RUNNER IIIS	Fixed-wing, single engine	Individual owner New Mexico	Experimental	2014-01-22	Valid
N55758	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Georgia	Experimental	2014-01-21	Valid
N44091	Halas Paul S-14-RANS	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2013-11-22	Valid
N44093	Halas Paul TITAN II TORONADO	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2013-11-22	Valid
N7712	Quicksilver MXL SPORT	Fixed-wing, single engine	Sky Knights Flight Club Thousand Oaks, California	Experimental	2013-09-26	Valid
N193AW	Gibson Mark MANTA 503	Weight-shift control	Individual owner Idaho	Experimental	2013-07-17	Valid
N4454E	Antares MA-32	Weight-shift control	Individual owner California	Experimental	2013-06-10	Valid
N352PK	Quicksilver SPORT	Fixed-wing, single engine	Individual owner Arizona	Experimental	2013-03-06	Valid
N93562	Quicksilver Enterprises Inc MX SPRINT	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2013-02-04	Valid
N263CS	Quicksilver MX II SPRINT	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2012-12-03	Valid
N264CS	Two Wings Aviation MARINER	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2012-12-03	Valid

Source: FAA Civil Aviation Registry, Releasable Aircraft Database (the engine reference table and each aircraft's engine code), October 5, 2026. Horsepower and thrust are the FAA's figures for the series, not for a particular aircraft.