High-Powered Brushless Aircraft Motors from O.S.!
Patent pending
Pilots loyal to outstanding O.S. performance but eager to fly electric now have the ideal option — powering electric airplanes using new O.S. brushless motors!
Designed by O.S. engineers to be the "gold standard" in electric power, these motors offer the same legendary quality and reliability that have O.S. glow engines famous worldwide for 75 years.
Only O.S. brushless motors offer a ventilation system that increases efficiency and allows the motors to generate additional power. Key to this system is a unique centrifugal fan design. The fan draws air through specially angled ventilation holes, across the windings and over the magnets for greatly improved cooling.
Other performance features of O.S. brushless motors include:

- A thick can design that resists distortion
- High-quality bearings
- Rigid and secure rear mounting design
- Shortened motor length for easy installation in short cowls
- A stainless steel prop shaft
- Supplied backplate, prop shaft, and gold-plated female plugs
With these brushless motors, O.S. reaffirms its standing as R/C's most innovative and respected resource for all model power needs. In the future look for more sizes and choices for car, helicopter and ducted fan modelers!
[ Click here for a review by RCGroups ]
OSMG9505
OMA-3805-1200 (.05 Size)
Rotor Diameter (mm): 38
Magnet Length (mm): 10
kV: 1200
Watts: 250
Weight (oz/g): 2.7 (76)
OSMG9510
OMA-3810-1050 (.10 Size)
Rotor Diameter (mm): 38
Magnet Length (mm): 10
kV: 1050
Watts: 333
Weight (oz/g): 3.6 (102)
OSMG9515
OMA-3815-1000 (.15 Size)
Rotor Diameter (mm):38
Magnet Length (mm):15
kV:1000
Watts:388
Weight (oz/g): 4.6 (130)
OSMG9525
OMA-3820-1200 (.25 Size)
Rotor Diameter (mm): 38
Magnet Length (mm): 20
kV: 1200
Watts: 440
Weight (oz/g): 5.5 (155)
OSMG9526
OMA-3820-960 (.25 Size Acro)
Rotor Diameter (mm): 38
Magnet Length (mm): 20
kV: 960
Watts: 450
Weight (oz/g): 5.6 (160)
OSMG9530
OMA-3825-750 (.30 Size)
Rotor Diameter (mm): 38
Magnet Length (mm): 25
kV: 750
Watts: 590
Weight (oz/g): 6.7 (190)
OSMG9538
OMA-5010-810 (4-stroke .52 size)
Rotor Diameter (mm): 50
Magnet Length (mm): 10
kV: 810
Watts: 700
Weight (oz/g): 8.3 (234)
OSMG9540
OMA-5020-490 (.40 Size)
Rotor Diameter (mm): 50
Magnet Length (mm): 20
kV: 490
Watts: 1110
Weight (oz/g): 12.3 (350)
OSMG9550
OMA-5025-375 (.50 Size)
Rotor Diameter (mm): 50
Magnet Length (mm): 25
kV: 375
Watts: 1550
Weight (oz/g): 14.3 (405)
O.S. Brushless Motor Dimensions O.S. Brushless Motor Specifications