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

Rotax 503 DCDI

560 aircraft on the U.S. register carry a Rotax 503 DCDI engine, rated at about 52 horsepower. The Quad City Ultralight Acft Corp CHALLENGER II is the model most often fitted with it (22 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 DCDI. FAA spelling: 503 DCDI.

Fitted to model families

Quad City Ultralight Acft Corp CHALLENGER II22Quicksilver GT-40011Kolb FIRESTAR II7Quad City Ultralights CHALLENGER II7Airborne REDBACK5Kolb Aircraft FIRESTAR II5Aerotrike SAFARI4Kolb FIRESTAR4Quad City CHALLENGER II4Air Creation TWIN3Cosmos BISON3Cosmos PHASE II3

Quad City Ultralight Acft Corp CHALLENGER II · Quicksilver GT-400 · Kolb FIRESTAR II · Quad City Ultralights CHALLENGER II · Airborne REDBACK · Kolb Aircraft FIRESTAR II · Aerotrike SAFARI · Kolb FIRESTAR · Quad City CHALLENGER II · Air Creation TWIN

Where they are owner's state

Wisconsin36California35Texas34Florida31Illinois25Alabama25Washington22Georgia22Michigan17Ohio16

Kind of aircraft

Piston singles427 (76%)Weight-shift and powered parachutes120 (21%)Helicopters7 (1%)Gyroplanes3 (0.5%)Gliders3 (0.5%)

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 22 with this engine series
Quicksilver GT-400 11 with this engine series
Kolb FIRESTAR II 7 with this engine series
Quad City Ultralights CHALLENGER II 7 with this engine series
Airborne REDBACK 5 with this engine series
Kolb Aircraft FIRESTAR II 5 with this engine series
Aerotrike SAFARI 4 with this engine series
Kolb FIRESTAR 4 with this engine series

Where they are

Wisconsin 36 of these aircraft
California 35 of these aircraft
Texas 34 of these aircraft
Florida 31 of these aircraft
Illinois 25 of these aircraft

Biggest operators

Evolution Aircraft INC 2 of these aircraft

Analytics

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

Aircraft newest certificates first · 560

Tail no.	Maker and model	Group	Owner and base	Certificate	Registered	Status
N372TF	Friesz Roger CHALLENGER II	Fixed-wing, single engine	Co-owned owner Washington	Experimental	2016-07-18	Valid
N9556Q	Thomas James R CGS HAWK	Fixed-wing, single engine	Individual owner Maryland	Experimental	2016-07-07	Valid
N574LT	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Mississippi	Experimental	2016-06-23	Valid
N1025Z	Lenaburg Allen G CHALLENGER I	Fixed-wing, single engine	Individual owner California	Experimental	2016-06-09	Valid
N503DB	Quad City Ultralights CHALLENGER II	Fixed-wing, single engine	Individual owner Florida	Experimental	2016-06-09	Valid
N303CW	Quad Cities Ultralights CHALLENGER II	Fixed-wing, single engine	Individual owner Illinois	Experimental	2016-03-19	Valid
N919KH	Detloff Dennis A D-1	Weight-shift control	Individual owner Washington	Experimental	2016-02-24	Valid
N503AK	Antares MA-33	Weight-shift control	Individual owner Alaska	Experimental	2016-02-04	Valid
N331RT	Tyler Robin A CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2016-01-22	Valid
N1864L	Brian Gafford DRIFTER MU582	Fixed-wing, single engine	Individual owner Ohio	Experimental	2015-11-06	Valid
N2522Y	Pegasus QUANTUM 15	Weight-shift control	Individual owner Illinois	Experimental	2015-10-29	Valid
N64326	Moriarity Duane A CHALLENGER II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2015-10-01	Valid
N87MZ	Harmening Mike HIGH FLYER	Powered parachute	Individual owner Wisconsin	Experimental	2015-09-30	Valid
N80538	Sorrell Aircraft Co Ltd SNS-9	Fixed-wing, single engine	Individual owner North Carolina	Experimental	2015-09-25	Valid
N56345	Pegasus QUANTUM503SUPERSPORT	Weight-shift control	Individual owner California	Experimental	2015-09-17	Valid
N876SR	Rager Steven W CHALLENGER II STAND	Fixed-wing, single engine	Individual owner Kentucky	Experimental	2015-09-03	Valid
N62CP	Rainbow Ltd AEROTRIKE SAFARI	Weight-shift control	Individual owner Nevada	Experimental	2015-08-17	Valid
N5050U	Challenger Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2015-08-06	Valid
N65QC	Lewis Robert A CHALLENGER II	Fixed-wing, single engine	Individual owner Virginia	Experimental	2015-07-23	Valid
N953HP	Perkins Howard RANS S-14	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2015-05-22	Valid
N35135	Baldwin Greg L FLIGHTSTAR 1	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2015-05-21	Valid
N650G	Air Creation GTE	Weight-shift control	Individual owner Arizona	Experimental	2015-05-04	Valid
N75444	Air Creation RACER 503SL	Weight-shift control	Individual owner California	Experimental	2015-04-01	Valid
N540ZM	Melin Carlyle A EINDECKER EIII	Fixed-wing, single engine	Co-owned owner Kansas	Experimental	2015-03-25	Valid
N134E	U-Fly-It Light Sport Acft Llc CHALLENGER II	Fixed-wing, single engine	Individual owner Arkansas	Experimental	2015-02-11	Valid
N6153	Lovel Richard L CHALLENGER 1	Fixed-wing, single engine	Individual owner Florida	Experimental	2014-12-04	Valid
N5664L	Quicksilver MX SPORT	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2014-11-18	Valid
N95054	Six Chuter Inc SR-2	Powered parachute	Fly Ppc LLC Bountiful, Utah	Experimental	2014-11-13	Valid
N65083	Dishon P James EXCALIBUR	Fixed-wing, single engine	Individual owner Arkansas	Experimental	2014-10-31	Valid
N51431	New Kolb Co FIRE STAR II	Fixed-wing, single engine	Individual owner Colorado	Experimental	2014-10-22	Valid
N4433H	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Oregon	Experimental	2014-09-24	Valid
N56CR	Redden Clifton M SKYRAIDER	Fixed-wing, single engine	Individual owner Kentucky	Experimental	2014-08-04	Valid
N95352	Steffes Dale CHALLENGER II	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2014-07-31	Valid
N1758C	Hill Merlin A CHALLENGER II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2014-07-29	Valid
N28LN	Norem Lawrence R CHALLENGER II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2014-06-30	Valid
N517YR	Michael Lee Robbins R-8	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2014-06-19	Valid
N234FD	Highcraft Aero-Marine Inc BUCCANEER XA	Fixed-wing, single engine	Individual owner Florida	Experimental	2014-06-11	Valid
N124ZX	Harmenings High Flyers DELUXE	Powered parachute	Individual owner Texas	Experimental	2014-06-06	Valid
N191SC	Six Chuter Inc LEGEND P103	Powered parachute	Individual owner Oregon	Light sport	2014-06-03	Valid
N61515	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Tennessee	Experimental	2014-05-05	Valid
N4877E	Brogdon George H HI-MAX 1700R	Fixed-wing, single engine	Individual owner California	Experimental	2014-04-10	Valid
N191PD	Powrachute RASCAL	Powered parachute	Deland Research CORP Deland, Florida	Experimental	2014-03-12	Valid
N75390	Kolb FIRESTAR II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2014-03-11	Valid
N1872C	Earthstar Aircraft Inc J24503	Fixed-wing, single engine	Individual owner California	Experimental	2014-03-10	Valid
N8029U	Crocker H L/Bura D CHALLENGER II	Fixed-wing, single engine	Individual owner New Jersey	Experimental	2014-03-07	Valid
N204PK	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2014-02-12	Valid
N125WD	Quad City Ultralight CHALLENGER II	Fixed-wing, single engine	Individual owner Florida	Experimental	2014-02-04	Valid
N630PH	Cosmos PHASE II	Weight-shift control	Individual owner Nevada	Experimental	2013-12-11	Valid
N312G	Dean James J FLIGHTSTAR I	Fixed-wing, single engine	Individual owner Mississippi	Experimental	2013-12-03	Valid
N3471	Thomas Robert CHALLENGER II	Fixed-wing, single engine	Thomas Robert Fort Atkinson, Wisconsin	Experimental	2013-11-25	Valid
N787SM	Mock D/Mock S HYPERHOPPER	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2013-11-01	Valid
N499EC	Russell David Collins CHALLENGER II	Fixed-wing, single engine	Individual owner Arkansas	Experimental	2013-10-29	Valid
N886S	Eichmann Richard W RG-1	Rotorcraft	Individual owner Arizona	Experimental	2013-10-24	Valid
N2812	Chicco Miguel E QUICKSILVER SPORT II	Fixed-wing, single engine	Sky Knights Flight Club Thousand Oaks, California	Experimental	2013-09-26	Valid
N2542A	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Co-owned owner Florida	Experimental	2013-09-04	Valid
N4750	Harmening High Flyer 503 DELUXE	Weight-shift control	Individual owner Maine	Experimental	2013-08-26	Valid
N740AB	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2013-08-05	Valid
N909DS	Daniel R Sepulveda RANS S-6ESTD COYOTE	Fixed-wing, single engine	Individual owner Puerto Rico	Experimental	2013-07-19	Valid
N3900A	Quicksilver MXII	Fixed-wing, single engine	Co-owned owner Kentucky	Experimental	2013-06-25	Valid
N396RB	Quad City Ultralight CHALLENGER 1 CW	Fixed-wing, single engine	Individual owner Michigan	Experimental	2013-06-18	Valid
N6116Z	Culver Steven L FERGUSON F2B	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2013-06-18	Valid
N35154	Titan TORNADO	Fixed-wing, single engine	Individual owner Iowa	Experimental	2013-05-10	Valid
N9092N	Quicksilver MXL II SPORT	Fixed-wing, single engine	Co-owned owner South Dakota	Experimental	2013-03-29	Valid
N56968	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Connecticut	Experimental	2013-01-16	Valid
N811EE	Flightstar SPYDER	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2013-01-15	Valid
N18XD	Casciola Dean E CHALLENGER II	Fixed-wing, single engine	Individual owner Massachusetts	Experimental	2012-12-21	Valid
N173CF	Six Chuter SKYE RYDER AEROCHUTE	Powered parachute	Individual owner Tennessee	Experimental	2012-12-04	Valid
N54EK	Pegasus Aviation QUANTUM 15	Weight-shift control	Individual owner Mississippi	Experimental	2012-11-28	Valid
N439EP	Pope Phil LIGHTNING	Weight-shift control	Individual owner Alabama	Experimental	2012-11-13	Valid
N3746S	Quicksilver SPRINT II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2012-09-24	Valid
N667TF	Anseeuw Brian J CHALLENGER II	Fixed-wing, single engine	Individual owner Iowa	Experimental	2012-09-21	Valid
N169A	New Kolb Aircraft Co FIRESTAR II	Fixed-wing, single engine	Individual owner New York	Experimental	2012-09-18	Valid
N48EC	Pegasus Aviation QUANTUM	Weight-shift control	Individual owner Indiana	Light sport	2012-09-14	Valid
N2736A	Titan Aircraft Co TORNADO I	Fixed-wing, single engine	Individual owner Indiana	Experimental	2012-08-02	Valid
N7093W	Phantom Aeronautics Llc PHANTOM	Fixed-wing, single engine	Individual owner Michigan	Experimental	2012-07-27	Valid
N176CB	Quad City Ultralights CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2012-07-03	Valid
N49LZ	Zimmerman Lawrence GARUDA	Rotorcraft	Individual owner Illinois	Experimental	2012-06-05	Valid
N80574	Benedict Samuel R QUICKSILVER GT 400	Fixed-wing, single engine	Individual owner Alabama	Experimental	2012-04-24	Valid
N8064A	Benedict Samuel R QUICKSILVER SPRNT II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2012-04-24	Valid
N466XS	Schultz Daniel M CHALLENGER 1	Fixed-wing, single engine	Individual owner New York	Experimental	2012-03-06	Valid
N3284S	Powrachute Corp SKY RASCAL	Powered parachute	Individual owner Utah	Experimental	2012-02-22	Valid
N4378A	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Vermont	Experimental	2011-11-10	Valid
N458HH	David L Holzheimer CHALLENGER II	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2011-10-31	Valid
N424NS	Schiller Douglas J CHALLENGER II	Fixed-wing, single engine	Individual owner Illinois	Experimental	2011-09-21	Valid
N248DE	Elliott Don JT-2 THUNDERGULL	Fixed-wing, single engine	Individual owner Washington	Experimental	2011-08-26	Valid
N56920	Kolb FIRESTAR II	Fixed-wing, single engine	Individual owner Mississippi	Experimental	2011-07-12	Valid
N92310	Kolb FIRESTAR II	Fixed-wing, single engine	Individual owner Georgia	Experimental	2011-06-22	Valid
N291BD	Dombrowski Byron D Ii CHALLENGER II	Fixed-wing, single engine	Individual owner Arizona	Experimental	2011-06-14	Valid
N126BW	Withrow Brian E BUCCANEER XA	Fixed-wing, single engine	Individual owner Florida	Experimental	2011-05-23	Valid
N905GF	Grant Finley J CHALLENGER	Fixed-wing, single engine	Individual owner Washington	Experimental	2011-05-09	Valid
N585U	Holland Emmett Wayne TITAN TORNADO	Gyroplane	Individual owner Idaho	Experimental	2011-04-06	Valid
N511GP	Cgs HAWK PLUS	Fixed-wing, single engine	Individual owner Nebraska	Experimental	2011-02-09	Valid
N2040D	Marcks Philip C BUCKEYE DM	Powered parachute	Individual owner Wisconsin	Experimental	2011-01-24	Valid
N260DB	Babcock Dayton STALKER	Weight-shift control	Individual owner Arizona	Experimental	2010-12-20	Valid
N503GC	Crone Glenn F CHALLENGER II	Fixed-wing, single engine	Individual owner Florida	Experimental	2010-12-03	Valid
N7779B	Schuster Randall J CHALLENGER II	Fixed-wing, single engine	Individual owner Iowa	Experimental	2010-09-30	Valid
N299KW	Work Kevin D CHALLENGER II	Fixed-wing, single engine	Individual owner Tennessee	Experimental	2010-06-25	Valid
N643RP	Purvis Ronald E RANS S-4 COYOTE	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2010-04-30	Valid
N1516L	Quad City Ultralight Acft Corp CH II	Fixed-wing, single engine	Individual owner Michigan	Experimental	2010-04-13	Valid
N3090J	Quicksilver MXL SPORT 2	Fixed-wing, single engine	Individual owner Hawaii	Experimental	2009-12-30	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.