Panther Drive Unit Series
The Panther Contra is a high-performance contra-drive system designed for full-scale 2M class F3A aircraft. All critical components—shafts, gears, and pulleys—are CNC-machined to ensure exceptional precision, durability, and smooth operation.
There are two versions of Contra drive. The one is complete version and another one is kit version.
Complete version (Coming soon in April)
This version is a complete contra drive unit that can be installed the airplane without separate assembly.
Kit version
This contra drive unit KIT version does not include a motor, propellers and unassembled. This is useful if you have a motor or want to buy it separately.
We recommend the motor Egodrift TENGU 4025EC (Eclipse) 650 Kv with a 40 mm outer shaft length, or any equivalent motor suitable for F3A contra applications and also recommended propellers is Falcon Carbon Prop 23 X 20 or 23.5 X 20 <- better*Notice : The 4 mounding holes of motor are should be M4 and distance between the holes is 30mm.
Specification
Weight: 182 g (without motor and mount)
Outer Size: 84 × 76 × 101 mm
External Shaft: Ø 6 mm × 40 mm length
Reduction Ratio: 4.77
Contents
Panther Contra Unit — 1 set
Mount Set (Ø 82 mm) — 1 set
Spinner Set (Ø 82 mm) — 1 set
Repair Parts for Panther Contra
Main Helical Gear
Belt HTD 207-3M
Inner Shaft
Collet Set
Motor Pulley & Gear
Prop Adapter
Motor Mount Set
Spinner Set
Ball Bearing Set
The Panther SD 70 is a single-belt drive unit designed specifically for 70-class F3A aircraft.
Notice
The motor is not included. Pilots may choose a motor based on their aircraft’s type and weight.
We recommend the Scorpion HK3226-1530 Kv or an equivalent motor for optimal performance.
Warning
The Panther operates at high rotational speeds. Always ensure that no people or objects are near the aircraft before operating.
If you experience unusual vibration or noise, stop operation immediately and investigate the cause.
Specification
Weight (without motor): 146 g
Size: 141.5 × 110 × 90 mm
Contents
Panther 70 — 1 pc
Motor Pulley (5 mm ID) — 1 pc
Motor Pulley (6 mm ID) — 1 pc
70 mm Mount Set — 1 set
Repair Parts for Panther 70
Belt: HTD204-3M
Collet Set
The Panther SD F3A is a single belt-drive system designed for full-scale 2M class F3A airplanes. All major components—including shafts, gears, and pulleys—are CNC-machined for high precision, durability, and smooth performance.
Notice
This drive unit does not include a motor.
For best results, we recommend the Egodrift TENGU 4025EC (Eclipse) 650 Kv motor with a 40 mm outer shaft length, or an equivalent motor suited for F3A single-drive applications.
Specification
Weight: 182 g (without motor and mount)
Outer Size: 84 × 76 × 101 mm
External Shaft: Ø 6 mm × 40 mm length
Reduction Ratio: 4.77
Contents
Panther SD F3A Unit — 1 set
Mount Set (Ø 82 mm) — 1 set
Repair Parts for Panther SD F3A
Pinion Pulley
Belt HTD 207-3M
High-efficiency motor drives engineered for smooth power delivery, precise control, and reliable performance in demanding RC aircraft setups.
PathFinder, Flight Logger for Model airplanes
The PathFinder is a high-precision flight logger for model aircraft, designed to record the aircraft’s position and orientation throughout the entire flight. It captures detailed flight-path and attitude data using a full suite of sensors, including:
3-axis gyros
3-axis accelerometers
Barometer
Magnetometer (compass)
GPS (15–25 samples per second)
This is the plug-and-play version — no calibration required. Insert a micro SD card, power it up, and you're ready to fly.
Specifications
Size: 75.5 × 41.5 × 17 mm (2.97" × 1.63" × 0.67")
Weight: 42 g (1.45 oz)
Input Voltage: 4.8 V ~ 7.4 V
Current Consumption: 30 mA
Connector: JR type, 250 mm lead
Contents
PathFinder — 1 pc
5V Regulator — 1 pc
Instruction Manual — 1 pc
Proton Sticker — 1 pc
Velcro Mount — 1 pc
Not included:
Micro SD card (use < 64 GB, Sandisk Extreme/Extreme Plus recommended)
USB 2.0 A Male → Micro B Male (5-pin) cable
Installation
Mount the PathFinder with the triangle marking facing forward, centered on the aircraft and parallel to the ground.
Connect the power plug to an unused receiver port.
If your receiver battery is 6–7.4 V, attach the included 5V regulator between the receiver and the PathFinder.
Insert a micro SD card into the slot on the side of the device.
Important:
Do not install the PathFinder close to the receiver, ESC, servos, or battery pack — these may interfere with GPS reception.
Although this unit is plug-and-play, periodic calibration improves long-term accuracy.
Operation
Power on the receiver.
Wait until the blue and yellow (or green) LEDs turn solid (not blinking) — this indicates sensor and GPS readiness.
Cold start: ~2 minutes
Warm start: ~30 seconds
Hot start: ~20 seconds
Take off and begin your flight.
PathFinder is a compact, high-precision flight logger for model aircraft, built to capture complete flight-path and attitude data from takeoff to landing. Using an advanced sensor suite—including 3-axis gyros and accelerometers, barometer, magnetometer, and high-rate GPS (15–25 Hz)—it records accurate position and orientation data for detailed post-flight analysis.
This plug-and-play version requires no calibration. Simply insert a microSD card, power it on, and fly.
Atom Servos
Clearance Sale
1 Pack: $5 → $4
5 Pack: $25 → $15
10 Pack: $50 → $20
The Story of Atom Servo
The Atom Standard Servo is engineered for pilots who need dependable, consistent performance at an exceptional value. Built around Proton’s FRF (Fiberglass Reinforced Frame) architecture, the Atom Standard delivers stable operation, precise movement, and long-term durability—making it a reliable choice for park flyers, trainers, sport models, and general RC applications.
The FRF Advantage
Our 20% Fiberglass Reinforced Frame (FRF) was developed after extensive structural testing to reduce case distortion and maintain alignment between the motor, gear set, and potentiometer. This results in:
Smooth, consistent gear movement
Reduced vibration effects
Improved centering precision
Better long-term durability
Designed for Reliability
The Atom Standard uses a brushed motor and a lightweight, efficient gear train. While it does not include ball bearings or O-rings (per the table specifications), the FRF frame provides enhanced structural rigidity—giving the Standard model excellent performance within its class.
Specifications
Modulation: Digital
Motor: Brushed (Mabuchi RF020TH)
Weight: 36 g
Input Voltage: 5 V
• 4.8 V direct use
• 6–12 V when used with included 5 V regulator
Torque: 3.10 kg-cm (43.0 oz-in)
Speed: 0.21 sec / 60°
Gear Type: Plastic (Torque Gear Set included)
Ball Bearings: None
O-Rings: None
Connector: JR
Contents (Per Set)
Atom Standard Servo — 1 pc
5V Servo Regulator — 1 pc
Servo Horn Set — 1 pc
Grommet Set — 1 pc
Clearance Sale
1 Pack: $15 → $5
5 Pack: $75 → $20
10 Pack: $150 → $30
The Story of Atom Servo
The Atom Marine Servo is purpose-built to handle wet, high-moisture, and water-spray environments. Using Proton’s FRF (Fiberglass Reinforced Frame) architecture combined with an O-ring sealing system, the Marine model offers enhanced protection against water intrusion while maintaining smooth and accurate control movement.
The FRF Advantage
Our 20% Fiberglass Reinforced Frame (FRF) reduces case distortion and maintains stable alignment between the motor, gear train, and potentiometer. This ensures:
Smooth and consistent servo operation
Improved centering precision
Increased durability, especially under vibration and mechanical load
Marine-Grade Sealing
Unlike the Standard and High Performance models, the Atom Marine Servo includes O-rings integrated into the FRF’s dual U-groove sealing system. When assembled, the upper and lower covers compress the O-rings to create a sealed enclosure—ideal for boats, marine aircraft, seaplanes, and other environments where moisture protection is essential.
Specifications
Modulation: Digital
Motor: Brushed (Mabuchi RF020TH)
Weight: 36 g
Input Voltage: 5 V
• 4.8 V direct use
• 6–12 V with included 5 V regulator
Torque: 3.10 kg-cm (43.0 oz-in)
Speed: 0.21 sec / 60°
Gear Type: Plastic (Torque Gear Set included)
Ball Bearings: None
O-Rings: Included
Connector: JR
Contents (Per Set)
Atom Marine Servo — 1 pc
5V Servo Regulator — 1 pc
Servo Horn Set — 1 pc
Grommet Set — 1 pc
Clearance Sale
1 Pack: $15 → $8
5 Pack: $75 → $35
10 Pack: $150 → $60
The Story of Atom Servo
The Atom High Performance Servo is designed for pilots who demand precision, speed, and power. Built on Proton’s FRF (Fiberglass Reinforced Frame) architecture, it delivers exceptional stability under load and maintains precise gear alignment—critical for high-performance aerobatics, competition flying, and advanced RC applications.
The FRF Advantage
The 20% Fiberglass Reinforced Frame (FRF) minimizes structural distortion and keeps the motor, gear train, and potentiometer perfectly aligned. This results in:
Faster response and smoother movement
Superior precision and repeatability
Increased durability under high torque loads
Engineered for High Voltage Power
With an HV-rated 7.4 V input, a coreless motor, and dual ball bearings, the High Performance model delivers significantly stronger torque and faster speed than the Standard version—making it ideal for demanding control surfaces.
(Note: The HP model does not include O-rings.)
Specifications
Modulation: Digital
Motor: Coreless
Weight: 35 g
Input Voltage: HV 7.4 V
Torque: 5.20 kg-cm
Speed: 0.18 sec / 60°
Gear Type: Plastic (Torque Gear Set included)
Ball Bearings: Dual ball bearings
O-Rings: None
Connector: JR
Contents (Per Set)
Atom High Performance Servo — 1 pc
Servo Horn Set — 1 pc
Grommet Set — 1 pc
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