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
N2481V	Quicksilver MXL II SPORT	Fixed-wing, single engine	Individual owner Ohio	Experimental	2023-07-09	Valid
N2551Y	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Nevada	Experimental	2023-06-29	Valid
N304CD	Ultralight Flight Inc PHANTOM	Fixed-wing, single engine	Individual owner Washington	Experimental	2023-06-17	Valid
N9321R	Bangert Lowell F CHALLENGER II	Fixed-wing, single engine	Individual owner Iowa	Experimental	2023-06-17	Valid
N2614T	Cosmos PHASE II	Weight-shift control	Individual owner Washington	Experimental	2023-06-10	Valid
N2678P	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Texas	Experimental	2023-06-07	Valid
N503DF	Reynolds Jackye S DEEREFLY TRIKE	Weight-shift control	Individual owner North Carolina	Experimental	2023-05-29	Valid
N512LM	Pegasus QUANTUM 15	Weight-shift control	Individual owner Kentucky	Experimental	2023-05-11	Valid
N4292G	Quad City Ultralight Acft Corp CHALLENGER SPECIAL	Fixed-wing, single engine	Individual owner South Dakota	Light sport	2023-05-05	Valid
N3973V	North Wing APPACHIE	Weight-shift control	Individual owner Texas	Experimental	2023-05-01	Valid
N213JB	Badessa John TITAN TORNADO II	Fixed-wing, single engine	Individual owner Texas	Experimental	2023-04-25	Valid
N2615T	Cosmos PHASE II	Weight-shift control	Individual owner New Mexico	Experimental	2023-04-22	Valid
N120UF	U-Fly-It Light Sport Acft Llc CHALLENGER II CWS	Fixed-wing, single engine	Individual owner Missouri	Experimental	2023-04-20	Valid
N6154R	Quicksilver MXLII SPRINT	Fixed-wing, single engine	Individual owner Georgia	Experimental	2023-04-11	Valid
N6170D	Aerotrike SAFARI	Weight-shift control	Individual owner Colorado	Experimental	2023-04-10	Valid
N5615B	Kolb FIRESTAR	Fixed-wing, single engine	Individual owner Idaho	Experimental	2023-04-05	Valid
N53GG	Earthstar Aircraft ODYSSEY	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2023-03-22	Valid
N5596V	Rathbun Robert M KOLB MARK II	Fixed-wing, single engine	Individual owner Iowa	Experimental	2023-03-20	Valid
N420KP	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Texas	Experimental	2023-03-18	Valid
N556TD	Pegasus Aviation QUANTUM 15	Weight-shift control	Individual owner Missouri	Experimental	2023-03-06	Valid
N380JM	Martin James A QUICKSILVER GT 400	Fixed-wing, single engine	Individual owner California	Experimental	2023-03-04	Valid
N7456B	Michael E Smith QUICKSILVER MXII	Fixed-wing, single engine	Individual owner Arkansas	Experimental	2023-02-28	Valid
N5518Y	Carlson Lloyd G CHALLENGER I	Fixed-wing, single engine	Individual owner Louisiana	Experimental	2023-02-25	Valid
N923FA	Fowler Patrick CHALLENGER II	Fixed-wing, single engine	Individual owner Ohio	Experimental	2023-02-21	Valid
N8083E	Kokkinos Hare RANS S.14	Fixed-wing, single engine	Individual owner Colorado	Experimental	2023-02-15	Valid
N878VB	David A Stirbis QUAD CITY CHLNGR CH2	Fixed-wing, single engine	Individual owner Colorado	Experimental	2023-01-27	Valid
N5949Y	Howard Rogers MXL II SPORT	Fixed-wing, single engine	Individual owner Texas	Experimental	2023-01-24	Valid
N5076G	Batman Wilbur D AEROTRIKE SCOUT	Weight-shift control	Individual owner Texas	Experimental	2023-01-12	Valid
N138JB	Beauboeuf Jeffrey M BEAUBOEUF FIRESTAR	Fixed-wing, single engine	Co-owned owner Massachusetts	Experimental	2023-01-03	Valid
N522DW	Willis Danny CHALLENGER II	Fixed-wing, single engine	Individual owner Oklahoma	Experimental	2022-12-15	Valid
N2090A	Byrd Kenneth A KOLB FIRESTAR II	Fixed-wing, single engine	Individual owner Colorado	Experimental	2022-12-14	Valid
N164ZX	Quad City Challenger CHALLENGER II	Fixed-wing, single engine	Individual owner Washington	Experimental	2022-12-10	Valid
N512JX	Cgs Aviation SINGLE SEAT CLASSIC	Fixed-wing, single engine	Individual owner Georgia	Experimental	2022-11-26	Valid
N356PS	Pergande Mark A CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2022-11-11	Valid
N5074J	Apollo JET STAR II	Weight-shift control	Individual owner Pennsylvania	Experimental	2022-11-09	Valid
N9434F	Ultralight Aircraft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner South Carolina	Experimental	2022-11-02	Valid
N5161V	Ultralight Flight Inc PHANTOM I	Fixed-wing, single engine	Co-owned owner Michigan	Experimental	2022-10-11	Valid
N108RG	Flying K Enterprizes SKY RAIDER II	Fixed-wing, single engine	Co-owned owner North Carolina	Experimental	2022-09-23	Valid
N61592	North Wing Design APACHE TRIKE	Weight-shift control	Individual owner New York	Experimental	2022-09-02	Valid
N4493G	Loehle Sport Parasol AIR CAMPER	Fixed-wing, single engine	Individual owner Washington	Experimental	2022-08-30	Valid
N613MD	Daugherty Monte R RIDGE RUNNER III	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2022-08-29	Valid
N187EJ	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner North Dakota	Experimental	2022-08-22	Valid
N5698T	Rfd Ultrawhite ULTRAWHITE	Gyroplane	Individual owner South Carolina	Experimental	2022-07-16	Valid
N75023	Deegan Michael J HORNET	Fixed-wing, single engine	Individual owner Washington	Experimental	2022-07-08	Valid
N5603U	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2022-06-08	Valid
N701GK	Challenger CHALLENGER I	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2022-06-06	Valid
N911UL	Quad City Ultralight Acft Corp CHALLENGER I	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2022-05-26	Valid
N4393G	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Texas	Experimental	2022-05-10	Valid
N963DG	Kolb FIRESTAR II	Fixed-wing, single engine	Individual owner Wyoming	Experimental	2022-04-29	Valid
N50903	Leon James M FLIGHTSTAR IISC	Fixed-wing, single engine	Individual owner North Carolina	Experimental	2022-04-19	Valid
N1453F	Gutierrez Jess R TALON MAGNUM	Fixed-wing, single engine	Individual owner Idaho	Experimental	2022-04-09	Valid
N6110R	Williford Drury F Jr CHALLENGER II	Fixed-wing, single engine	Individual owner Mississippi	Experimental	2022-04-08	Valid
N8113Y	Adams Dale HORNET	Fixed-wing, single engine	Individual owner Georgia	Experimental	2022-02-22	Valid
N5518L	North Wing Design Inc APACHE CLASSIC	Weight-shift control	Individual owner Maine	Experimental	2022-02-17	Valid
N6964R	Quad City Ultralights CHALLENGER II	Fixed-wing, single engine	Individual owner Texas	Experimental	2021-12-09	Valid
N1701B	Maxair DRIFTER XP	Fixed-wing, single engine	Kedish Kirk Helena, Montana	Experimental	2021-12-06	Valid
N75185	Behrendt John P THUNDERGULL 2000	Fixed-wing, single engine	Individual owner Washington	Experimental	2021-10-29	Valid
N10342	Golden Circle TBIRD I	Fixed-wing, single engine	Individual owner New Mexico	Experimental	2021-10-28	Valid
N405AC	Campbell Arnold CHALLENGER 2	Fixed-wing, single engine	Individual owner Indiana	Experimental	2021-10-20	Valid
N682FS	Kolb Aircraft FIRESTAR II	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2021-10-12	Valid
N2753	Moughan James J RANS S-5 COYOTE	Fixed-wing, single engine	Masterson Paul C Windsor, Missouri	Experimental	2021-09-22	Valid
N370BP	Rundall Dg/Kirkpatrick Dg CHALLENGER E LSS	Fixed-wing, single engine	Individual owner Virginia	Experimental	2021-09-08	Valid
N51722	Kolb Aircraft FIRESTAR II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2021-08-28	Valid
N99TY	Young Terry J SR2	Powered parachute	Individual owner Tennessee	Experimental	2021-08-21	Valid
N93106	Hladilek Anthony T F QUICK E	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2021-08-17	Valid
N7094T	Kolb FIRESTAR II	Fixed-wing, single engine	Individual owner New York	Experimental	2021-08-07	Valid
N7029N	Flightstar Sportplane SPYDER	Fixed-wing, single engine	Individual owner Mississippi	Experimental	2021-06-28	Valid
N2494X	Parham John B Iii FERGY II B	Fixed-wing, single engine	Individual owner Georgia	Experimental	2021-06-22	Valid
N50548	Bjornstad Norman L FRIGATE	Weight-shift control	Co-owned owner Arizona	Experimental	2021-06-11	Valid
N5119V	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner North Carolina	Experimental	2021-06-02	Valid
N7511Y	Cosmos BISON	Weight-shift control	Individual owner Texas	Experimental	2021-06-01	Valid
N3039G	Lindquist F R /Mcdonnell Tim R CHALLENGER II	Fixed-wing, single engine	Individual owner Ohio	Experimental	2021-05-25	Valid
N375HH	New Kolb Aircraft Co FIRESTAR II	Fixed-wing, single engine	Individual owner Washington	Experimental	2021-05-20	Valid
N45575	Weber Eugene F BEE DIFFERENT	Rotorcraft	Individual owner Florida	Experimental	2021-05-18	Valid
N899RD	Larry W Dunn QUAD CITY ACFT CHALL	Fixed-wing, single engine	Individual owner Missouri	Experimental	2021-05-12	Valid
N7065Y	Martin Helen Tabor RIDGE RUNNER	Fixed-wing, single engine	Individual owner California	Experimental	2021-05-07	Valid
N4145S	Strickland Benjamin F CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2021-05-05	Valid
N3094K	Reed Robert A CHALLENGER I CWS	Fixed-wing, single engine	Individual owner Texas	Experimental	2021-05-03	Valid
N21PR	Reneberg-Peck QUICKIE	Fixed-wing, single engine	Individual owner Kansas	Experimental	2021-04-27	Valid
N8507V	Holland Henry L TITAN A/C TORNADO I	Fixed-wing, single engine	Individual owner Arkansas	Experimental	2021-04-24	Valid
N7UL	Addison Keith E QUICKSILVER SPRINTII	Fixed-wing, single engine	Taylor Aviation INC North Aurora, Illinois	Experimental	2021-04-23	Valid
N95386	Aerochute Ind Pty Ltd AEROCHUTE	Powered parachute	Individual owner Illinois	Experimental	2021-04-19	Valid
N7072Z	Alfred Keith SKY RAIDER II	Fixed-wing, single engine	Individual owner California	Experimental	2021-03-24	Valid
N7043P	New Kolb Aircraft Co FIRESTAR II	Fixed-wing, single engine	Individual owner Texas	Experimental	2021-03-23	Valid
N657SB	Near Thomas C CHALLENGER II	Fixed-wing, single engine	Individual owner Kansas	Experimental	2021-03-01	Valid
N748JB	Benton James H Jr CHALLENGER II	Fixed-wing, single engine	Individual owner Georgia	Experimental	2021-02-20	Valid
N6052E	Glover E R KOLB FIRESTAR II	Fixed-wing, single engine	Individual owner California	Experimental	2021-02-19	Valid
N3010F	North Wing APACHE	Weight-shift control	Individual owner Arkansas	Experimental	2021-02-09	Valid
N898NT	Taylor Gregory S EXCALIBUR	Fixed-wing, single engine	Individual owner Ohio	Experimental	2021-01-25	Valid
N2710N	Eipper Acft Inc QUICKSILVER MF	Fixed-wing, single engine	Individual owner Oregon	Experimental	2021-01-23	Valid
N105CE	Fly Virginia Beach Inc NORTHWING COYOTE	Weight-shift control	Individual owner New Jersey	Experimental	2021-01-13	Valid
N987Y	Hytek HURRICANE	Fixed-wing, single engine	Individual owner California	Experimental	2021-01-09	Valid
N142DH	Pegasus SUPER SPORT	Weight-shift control	Individual owner Missouri	Experimental	2021-01-07	Valid
N2825N	Lockwood Leeza DRIFTER	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2021-01-06	Valid
N80422	Slipstream REVELATION	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2021-01-06	Valid
N2532N	Six Chuter Inc SR7	Powered parachute	Tom Dodson LLC Leonard, Oklahoma	Experimental	2020-12-30	Valid
N34FS	Fasone Philip R FLIGHTSTAR IISC	Fixed-wing, single engine	Individual owner Georgia	Experimental	2020-12-21	Valid
N183SW	Whitley Scott CHALLENGER II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2020-12-17	Valid
N6115Y	Davis Brent QUICKSILVER	Fixed-wing, single engine	Individual owner California	Experimental	2020-12-10	Valid
N2647T	Challenger SINGLE SEAT LW	Fixed-wing, single engine	Individual owner Kentucky	Experimental	2020-12-03	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.