Engines · two-cycle piston · data as of October 7, 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

Model families, as a table

	aircraft
Quad City Ultralight Acft Corp CHALLENGER II	22
Quicksilver GT-400	11
Kolb FIRESTAR II	7
Quad City Ultralights CHALLENGER II	7
Airborne REDBACK	5
Kolb Aircraft FIRESTAR II	5
Aerotrike SAFARI	4
Kolb FIRESTAR	4
Quad City CHALLENGER II	4
Air Creation TWIN	3
Cosmos BISON	3
Cosmos PHASE II	3

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

Wisconsin36California35Texas34Florida31Illinois26Alabama25Washington22Georgia22Michigan17Ohio16

By state, as a table

	aircraft
Wisconsin	36
California	35
Texas	34
Florida	31
Illinois	26
Alabama	25
Washington	22
Georgia	22
Michigan	17
Ohio	16

Kind of aircraft

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

By kind, as a table

	aircraft	share
Piston singles	427	76%
Weight-shift and powered parachutes	120	21%
Helicopters	7	1%
Gyroplanes	3	0.5%
Gliders	3	0.5%

When the aircraft were built by decade

By decade built, as a table

	aircraft
1960	1
1980	23
1990	124
2000	247
2010	52
2020	12

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 26 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
N455T	Aero Trike SAFARI	Weight-shift control	Individual owner Illinois	Experimental	2007-06-14	Valid
N2055S	Graves David A CHALLENGER 1	Fixed-wing, single engine	Individual owner Indiana	Experimental	2007-06-13	Valid
N70577	Quitoriano Don MXLII	Fixed-wing, single engine	Individual owner Arizona	Experimental	2007-06-08	Valid
N77DK	Kelley Daniel S KELLEY ONE	Fixed-wing, single engine	Individual owner California	Experimental	2007-06-08	Valid
N62ET	Hipps RELIANT SX	Fixed-wing, single engine	Individual owner Florida	Experimental	2007-06-07	Valid
N2534J	Air Creation TWIN 503 TRIKE	Weight-shift control	Individual owner Wisconsin	Experimental	2007-06-06	Valid
N51641	Flightstar IISC	Fixed-wing, single engine	Individual owner Wisconsin	Experimental	2007-05-31	Valid
N5173J	Destiny VISION	Powered parachute	Individual owner Illinois	Experimental	2007-05-29	Valid
N157HT	Thresher Harry L CHALLENGER 2 LW	Fixed-wing, single engine	Individual owner Missouri	Experimental	2007-05-18	Valid
N38BV	Quad Cities Aircraft CHALLENGER II	Glider	Individual owner New York	Experimental	2007-05-17	Valid
N8595X	Murphy Don J CHALLENGER IISPECIAL	Fixed-wing, single engine	Individual owner Illinois	Experimental	2007-05-17	Valid
N104LH	Hood Lloyd A AIR CREATION GTE	Weight-shift control	Individual owner Alaska	Experimental	2007-05-09	Valid
N1610N	Airborne REDBACK	Weight-shift control	Individual owner Georgia	Experimental	2007-05-04	Valid
N184CT	Moore Steven J TUKAN TRIKE	Weight-shift control	Individual owner Colorado	Experimental	2007-04-30	Valid
N2552S	Phantom Aircraft Co PHANTOM X-1	Fixed-wing, single engine	Individual owner Michigan	Experimental	2007-04-25	Valid
N667W	Aerotrike SAFARI	Weight-shift control	Individual owner Washington	Experimental	2007-04-24	Valid
N426RF	Fernandez Robert DESTINY 2000	Powered parachute	Individual owner Illinois	Experimental	2007-04-12	Valid
N709FS	Kolb Aircraft FIRESTAR II	Fixed-wing, single engine	Individual owner Florida	Experimental	2007-04-10	Valid
N579RF	Quicksilver GT-400	Fixed-wing, single engine	Individual owner Illinois	Experimental	2007-04-04	Valid
N86030	Hurricane Co Inc TM CLIPPED WING	Fixed-wing, single engine	Individual owner California	Experimental	2007-04-04	Valid
N8604L	Hurricane Co Inc HAULER	Fixed-wing, single engine	Individual owner California	Experimental	2007-04-04	Valid
N202FS	Flightstar Inc FS-II	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2007-03-01	Valid
N40298	Six Chuter SR2	Powered parachute	Individual owner Wisconsin	Experimental	2007-02-06	Valid
N4020H	Quicksilver MXL II	Fixed-wing, single engine	Individual owner Minnesota	Experimental	2007-02-05	Valid
N229K	Kolb FIRESTAR II	Fixed-wing, single engine	Individual owner Michigan	Experimental	2007-01-31	Valid
N9062U	Neuman Michael R HURRICANE	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2007-01-30	Valid
N503XT	Airborne Windsports REDBACK TRIKE	Weight-shift control	Individual owner Missouri	Experimental	2007-01-29	Valid
N7049J	Flightstar Inc SPYDER	Fixed-wing, single engine	Individual owner Pennsylvania	Experimental	2007-01-17	Valid
N771AW	Wallace Larry Alfred TUKAN	Weight-shift control	Individual owner Alabama	Experimental	2007-01-04	Valid
N862P	Air Creation TWIN	Weight-shift control	Individual owner Illinois	Experimental	2007-01-04	Valid
N94436	Air Creation TWIN	Weight-shift control	Individual owner Maine	Experimental	2006-10-31	Valid
N416B	Quad City Ultralight Acft Corp CHALLENGER II	Fixed-wing, single engine	Individual owner Georgia	Experimental	2006-10-24	Valid
N8021F	Hablutzel Ronnie E RAPTOR	Weight-shift control	Individual owner California	Experimental	2006-09-26	Valid
N145JB	Welch John T WEEDHOPPER 2	Fixed-wing, single engine	Individual owner Texas	Experimental	2006-09-21	Valid
N119HB	Harris Brock E CHALLENGER II	Fixed-wing, single engine	Individual owner Washington	Experimental	2006-09-13	Valid
N46DN	Nicoson David H SIX CHUTER SKYRIDER	Powered parachute	Individual owner Wisconsin	Experimental	2006-09-11	Valid
N190PC	Quadcity Ultralights CHALLENGER II	Fixed-wing, single engine	Ultra Flight LLC Le Mars, Iowa	Experimental	2006-08-28	Valid
N93JB	Antares MA 31	Weight-shift control	Individual owner Alaska	Experimental	2006-08-23	Valid
N34MG	Graber Michael L T-BIRD T II	Fixed-wing, single engine	Individual owner Iowa	Experimental	2006-08-22	Valid
N30438	Gossett Daniel D CHALLENGER II	Fixed-wing, single engine	Individual owner Ohio	Experimental	2006-08-08	Valid
N662M	Tyre Danny J CHALLENGER II	Fixed-wing, single engine	Individual owner Georgia	Experimental	2006-07-25	Valid
N763T	Pegasus QUANTUM	Weight-shift control	Individual owner Wisconsin	Experimental	2006-07-07	Valid
N9034H	Silverwing Aviation Llc CHALLENGER II	Fixed-wing, single engine	Individual owner Missouri	Experimental	2006-06-26	Valid
N5080K	Lee Raymond H QUAD CITY CHALLENGER	Fixed-wing, single engine	Individual owner Texas	Experimental	2006-06-21	Valid
N3145	Edwards B-8M	Rotorcraft	Individual owner Arkansas	Experimental	2006-06-06	Valid
N17JX	Gilkey Jeffrey C AEROTRIKE COBRA	Weight-shift control	Individual owner New Mexico	Experimental	2006-04-21	Valid
N213FW	Walker Frederick C RAGWING SPECIAL	Fixed-wing, single engine	Individual owner Indiana	Experimental	2005-12-14	Valid
N924PJ	Bowden Mark H QCU CH II	Fixed-wing, single engine	Individual owner Alabama	Experimental	2005-04-15	Valid
N139SW	J & J Ultralights J&J TUKAN SE	Weight-shift control	Individual owner Florida	Experimental	2005-03-14	Valid
N670BV	Viele Bruce L QUAD CITY CHLNGER II	Fixed-wing, single engine	Individual owner Florida	Experimental	2002-02-05	Valid
N6080M	Cottrell Larry J KOLB FIRESTAR II	Fixed-wing, single engine	Individual owner Oregon	Experimental	2000-04-07	Valid
N106BL	Leftwich Brian L LEFTWICH SPRINT	Fixed-wing, single engine	Individual owner Ohio	Experimental		Pending
N112CL	Apex APEX CROSS-5X	Weight-shift control	Individual owner Illinois	Experimental		Sale reported
N203SD	Donahue Stephen J FIRESTAR II	Fixed-wing, single engine	Individual owner Florida	Experimental		Pending
N271SW	Rocky Mountain Wings Llc RIDGE RUNNER II	Fixed-wing, single engine	Individual owner Texas	Experimental		Pending
N31622	Quad City Ultralight Inc CHALLENGER II	Fixed-wing, single engine	Individual owner Louisiana	Experimental		Pending
N4404G	Brown Ransford E CHALLENGER II	Fixed-wing, single engine	No owner on file	Experimental		Assigned, not yet registered
N61211	Pegasus QUANTUM	Weight-shift control	Evolution Aircraft INC Zephyrhills, Florida	Experimental		Valid
N722QD	Shuman Donald J CHALLENGER II	Fixed-wing, single engine	Individual owner Wisconsin	Experimental		Canceled
N75656	Cosmos BISON	Weight-shift control	Evolution Aircraft INC Zephyrhills, Florida	Experimental		Valid

Source: FAA Civil Aviation Registry, Releasable Aircraft Database (the engine reference table and each aircraft's engine code), October 7, 2026. Horsepower and thrust are the FAA's figures for the series, not for a particular aircraft.