🎯 Overview
⚠️ IMPORTANT WARNING
This instrument is intended for situational awareness enhancement only. DO NOT use as primary navigation instrument!
Use of the program removes any responsibility from developers. Always rely on certified aviation instruments for critical decisions in flight.
EFU (Electronic Flight Unit) is a modern electronic flight instrument system (EFIS) designed for general aviation. The system provides integrated display of all primary flight parameters on a single high-quality display.
Artificial Horizon
Accurate display of roll and pitch with dynamic error compensation
Heading Indicator
Electronic compass with turn indicator and course marker setting
Altimeter
Digital altimeter with QNH/QFE support and barometric correction
Airspeed Indicator
Color-coded V-speed arcs with configurable boundaries
Variometer
High-sensitivity vertical speed indicator
GPS Navigation
Display of ground speed, course and coordinates
⚙️ Technical Specifications
Display
- Type: FT8xx EVE TFT
- Resolution: 0.01 hPa
- Size: 4.3 inches
- Brightness: Adjustable 0-500
Power
- Voltage: 12V/24V aircraft power
- Consumption: ~150 mA
- Protection: Reverse polarity
- Filtering: Interference protection
Interfaces
- Encoder: Menu navigation
- UART2: AHRS sensor
- UART3: GPS module
- I2C: Pressure sensors
Working Conditions
- Temperature: -20°C...+70°C
- Humidity: Up to 95% without condensation
- Vibration: Aviation
- Altitude: Up to 18,000 m
🔬 Sensors
🚀 3-Space™ Nano Carrier Board - AHRS System Heart
This is a professional AHRS sensor from Yost Labs - the real pride of our system!
🎯 Incredible Accuracy
- 9-axis motion sensor
- Heading accuracy: ±2°
- Roll/pitch accuracy: ±1°
- Update rate: 100 Hz
🧠 Intelligent Calibration
- Automatic drift compensation
- Adaptive noise filtering
- System self-diagnosis
- Magnetic interference compensation
💪 Reliability
- Military quality standard
- Vibration resistance
- Temperature compensation
- Long service life
⚡ Performance
- Ready time: <30 sec
- Low power consumption
- Digital data output
- Advanced fusion algorithms
💧 Pressure measurement system
Static port (BMP280 @ 0x77)
- Accuracy: ±1 hPa
- Resolution: 0.01 hPa
- Range
- Function
Pitot (BMP280 @ 0x76)
- Accuracy: ±1 hPa
- Sensitivity: High
- Response: Fast
- Function: Airspeed measurement
🛰️ GPS System
GPS Capabilities
- Ground Speed (GS): Accuracy up to 0.1 km/h
- Course Over Ground (COG): Magnetic and true
- GPS Altitude: Additional barometric altitude check
- UTC Time: Automatic synchronization
- Number of satellites: Signal quality indication
🎛️ Instruments
🎯 Artificial Horizon
Display Features
- Dynamic sky: Color changes depending on pitch
- Colored ground: Reddish tint during descent
- Roll angles: Marks 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°
- Yellow airplane: Fixed aircraft symbol
- Turn indicator: Standard and accelerated scale
💨 Airspeed Indicator
| Color Arc | Purpose | Setting | Typical Values |
|---|---|---|---|
| White Arc | Flap range | WA Start - WA End | 0-500 km/h |
| Green Arc | Normal flight | GA Start - GA End | 0-500 km/h |
| Yellow Arc | Caution | GA End - Red Line | 0-500 km/h |
| Blue Line | Optimal gliding speed | Blue Line | 0-500 km/h |
| Red Line | VNE - never exceed | Red Line | 0-500 km/h |
📏 Altimeter
Barometric correction modes
- QNH mode: Altitude above sea level (standard pressure 1013.25 hPa)
- QFE mode: Altitude above aerodrome (shows 0 at current altitude)
- Automatic QFE calculation: System calculates aerodrome pressure automatically
- Manual correction: Ability to enter exact pressure
📈 Variometer (VSI)
High-sensitivity system
- Range: Configurable ±5...±50 m/s
- Sensitivity: Adjustable gain coefficient
- Smoothing: Adaptive filtering
- Units: m/s or ft/s
- Color indication: Green dynamic line
⏱️ Flight timer system
Current flight
- Format: HH:MM:SS
- Automatic start/stop
- Memory when powered off
Total time
- Flight counter
- Hours counter
- EEPROM storage
🎮 System Operation
🚀 Startup and Initialization
Startup Sequence
- Power Supply: System automatically turns on
- Boot Screen: Displayed for 8 seconds with "eFlyUnit" text
- Sensor Check: Automatic diagnostics:
- Pitot Port Sensor @ 0x76
- Yost Labs AHRS Sensor on UART2
- Ready to work: Switch to main screen
🎛️ Encoder Control
| Action | Function | Mode |
|---|---|---|
| Rotate left/right | Menu navigation | Main screen |
| Press | Enter selected menu | Main screen |
| Rotate in menu | Change value | Settings mode |
| Press + rotate | Quick change | Settings mode |
| Press in menu | Exit/save | Settings mode |
📊 Status Indication
Screen Indicators
- Snsr Err: Sensor status (green = OK, red = error)
- GPS data: GS (ground speed), ALT (GPS altitude), COG (course over ground)
- Flight timer: Current flight (HH:MM:SS) and total flight time (HHH:MM)
- Red X: Critical sensor error - DO NOT NAVIGATE!
⚠️ Warning Modes
Safety System
- AHRS Loss: Red X displayed when AHRS sensor communication is lost
- Sensor Error: "Snsr Err" indicator turns red
- Speed Limit Exceeded: System warns when red line speed is exceeded
- GPS Loss: "---" displayed instead of GPS values
🎯 Calibration and Setup
🧭 AHRS Calibration (3-Space™ Nano)
Complete AHRS Calibration Procedure
- Preparation: Place instrument in horizontal position, nose to magnetic north
- Menu entry: CALIB → RESET AHRS
- Confirmation: Turn encoder right to select "Zero AHRS and Save"
- Execution: Press encoder to start calibration
- Waiting: Do not touch instrument for 30-60 seconds
- Completion: System will automatically save settings
⚖️ Precise Offset Calibration
| Parameter | When to Calibrate | Method | Adjustment step: 0.1 units for precise tuning |
|---|---|---|---|
| Roll Offset | Roll not zero in level flight | Set wings level, adjust | 0.5° (0.00872 rad) |
| Pitch Offset | Pitch does not match actual | Level flight, correction by reference | 0.5° (0.00872 rad) |
| Compass Dev | Heading does not match magnetic compass | Compare with calibrated compass | 0.5° |
🌡️ Pressure Sensor Calibration
Calibration Sequence
- Static Calib:
- Compare altitude reading with known airport elevation
- Each correction unit ≈ 8 meters (25 feet)
- Range: -10...+10
- Pitot Calib:
- Compare speed reading with GPS or reference instrument
- Each correction unit ≈ 1 mile/hour
- Range: -70...+70
📈 Variometer Sensitivity Setup
Variometer Operation Optimization
- Low sensitivity (-5.5...-1.0): For calm air, less "jerky"
- Medium sensitivity (-1.0...+1.0): Universal setting
- High sensitivity (+1.0...+5.5): For thermal hunting, maximum reaction
- Adjustment step: 0.1 units for precise tuning
🔧 Troubleshooting
❌ Common Problems
🚨 Erratic Artificial Horizon
Cause: AHRS calibration needed
Solution: Perform level and compass calibration
- Check UART2 connection, restart system
📊 Wrong Altitude Reading
Cause: Incorrect QNH/QFE setting
Solution: Set correct barometric pressure
🌐 No GPS Signal
Cause: Poor satellite reception
Solution: Check antenna, wait for signal acquisition
⚙️ Diagnostic Codes
| Indicator | State | Value | Action |
|---|---|---|---|
| Snsr Err | Green | All sensors working | Normal operation |
| Snsr Err | Red | Sensor Error: "Snsr Err" indicator turns red | Check connections |
| Static Port Sensor | NOT FOUND @ 0x77 | Altitude sensor not found | Check I2C connection |
| Pitot Port Sensor | NOT FOUND @ 0x76 | Speed sensor not found | Check I2C connection |
| AHRS Sensor | Searching on UART2 | Searching AHRS sensor | Check UART2 connection |
🔄 Factory Reset
Full system reset
- Enter CONF → RST menu
- Confirm "YES" in reset dialog
- IMPORTANT: After pressing YES wait 10-30 seconds
- System will restart automatically
- All settings will return to factory defaults
- AHRS recalibration will be required
📞 Technical Support
Website: www.eFlyUnit.com