1. Introduction

SafePanel™ combines a solid-state turn coordinator + inclinometer with altitude, VSI, and—when connected to the optional Airspeed (ASI) dongle—a live airspeed tape + digital readout.
Without the dongle, SafePanel defaults to displaying AGL instead of airspeed.

SafePanel installs in any 2¼″ or 3⅛″ instrument hole and continuously charges from the aircraft bus, maintaining its internal battery as a self-contained reserve.
If the bus power is lost or disconnected, the unit alerts the pilot and continues operating on its internal battery.

SafePanel is an advisory-use instrument, not TSO’d, and is intended for situational awareness and redundancy in Experimental and General Aviation aircraft.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

​2. Specifications

• Display:   2" Sunlight Readable

• Functions: Turn Coordination, Slip / Skid ball, Digital Altimeter, Digital Above Ground Level (AGL) Altimeter, AGL Tape, Digital VSI, VSI Tape, Optional ASI, Optional ASI Tape, Settable Kollsman Window

• Mounting:  2 1/4" or 3 1/8" panel hole (notch required for full 2 1/4" display)

• Power:  Input  9 to 30V

• Power Consumption: 160mah maximum, full bright screen + charging

• Battery:  Internal Lithium for backup (500mah) (4 hours of usage)

• Controls:  Kollsman Up / Down; Dim; Gyro Setting; General Setup

• ALERT:  Shows when external power is present or absent

• Weight:  Approximately two ounces (55 grams)

• Thickness: Approximately 0.75" (2 cm)​

 

​​​​​​​​​​​​​​​​​​3. Controls and Indicators

Front Display

• Turn indicator with smooth bar and digital yaw rate

• Slip/skid ball for coordination

• Digital altitude and Kollsman setting

• VSI digital readout and trend tape

• AGL digital readout and tape (or ASI digital and tape when dongle connected)

• Battery and bus-power status icons

• BUS DISCONNECTED alert indicator

Buttons

• Short press 

  • Left: Kollsman down

  • Right: Kollsman up

  • Both: set STD (29.92 inHg / 1013.5 hPa)

• Long press / hold

  • Left long: brightness step (keep holding to roll)

  • Both long: gyro filter 0→1→2→3→0

  • Right hold: CAL (hold until “CAL” appears; unit saves offsets and reboots)

Settings are retained across power cycles.

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4. Power and Charging

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SafePanel is wired to the aircraft’s 14 V or 28 V bus and automatically maintains charge on its internal Li-ion cell. No pilot action is required; charging is automatic whenever external power is present.

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If the bus disconnects (breaker pull, master off, etc.), the unit automatically switches to battery power and alerts the pilot (and continues operating).

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28 V bus operation (required external resistor): If you power SafePanel from a 28 V aircraft bus, you must install an external series resistor in the power lead to limit input power and heat. Use a 91 Ω, 5 W (minimum) resistor (a 5 W part is recommended). This resistor is not supplied by Radiant. A suitable example is Yageo SQP500JB-91R (91 Ω, 5 W) — available from DigiKey as 91W-5-ND (DigiKey) and from Mouser as 603-SQP500JB-91R (mouser.com). (Equivalent 91 Ω, ≥5 W resistors are acceptable; mount where it can safely dissipate heat.)

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5. Mounting and Installation

• Fits any standard 2¼″ or 3⅛″ instrument cutout.

• Use included mounting ring and hardware.

• Connect aircraft power (typically +12–28 V and GND).

• Optional: connect Radiant ASI dongle to the rear RS-485 connector if airspeed display is desired.

• Avoid mounting near high heat sources or magnetic disturbances.

 

6. Setup and Configuration (AGL only units)

Important: Setup is entered at power-on

SafePanel’s configuration “wizard” is only entered during boot via a power-on button hold. “In-flight” menu navigation is not how this firmware configures the unit.

6.1 Entering Setup (AGL configuration wizard)

1. Power the unit OFF.

2. Press and hold the LEFT button, then power the unit ON.

3. The unit will display the first setup prompt (see next section). Release the button and follow the prompts.

6.2 Step 0 — Select Kollsman units (inHg vs hPa)

On entry, SafePanel shows a two-choice prompt:

• Left box: 2992 (29.92 inHg)

• Right box: 1013 (represents 1013.5 hPa “standard”; stored internally as 10135)

To prevent accidental selection, the firmware arms only after both buttons have been released once. Then the first press chooses the units:

• Press LEFT → select inHg

• Press RIGHT → select hPa

The choice is saved to flash and held on-screen briefly for confirmation.

6.3 Steps 3–6 — Program the AGL tape landmarks (Val0–Val3)

After units selection, the wizard programs four AGL “landmark” values (0–9999). These define how the AGL tape behaves (including the top of tape clamp).

You will set:

• #3 → Val0 (usually 400 feet AGL)

• #4 → Val1 (usually 800 feet AGL)

• #5 → Val2 (usually 900 feet AGL)

• #6 → Val3 (usually 1200 feet AGL)

Editing controls inside the wizard:

• Left short: −1

• Right short: +1

• Left long: −10

• Right long: +10

• Both long: commit/advance to next step

Validity rules (must be strictly increasing):
Val1 > Val0, Val2 > Val1, Val3 > Val2, and Val3 < 10000.

If valid, the values are saved to flash and used immediately for AGL behavior.

6.4 Quick restore: Default “VFR pattern” AGL profile

If you want to quickly restore the default AGL landmarks:

1. Power the unit OFF

2. Hold RIGHT while powering ON

This forces and saves the defaults:

• Val0 = 400

• Val1 = 800

• Val2 = 900

• Val3 = 1200

 

7. Calibration (CAL)

Perform calibration on a level surface or in straight-and-level flight.

1. Hold Right ≥ 7 s.

2. Display shows “CAL.” Offsets are stored and the unit reboots.

Calibrate whenever the ball appears off-center in level flight or after installation angle changes.

 

8. Normal Operation

• Unit powers on automatically with aircraft bus.

• Display shows Turn + Slip/Skid, Altitude + Kollsman, VSI, and AGL or ASI depending on dongle presence.

• Brightness and filter preferences remain as last set.

• If bus voltage drops or disconnects, “BUS DISCONNECTED” appears and internal battery takes over.

• When bus returns, charging resumes automatically.

• AGL zero is auto-captured on first valid altitude after boot.

• AGL is clamped to your top-of-tape value (Val3 behavior).

 

​​​​​​​​​​9. Safety and Regulatory

SafePanel is an advisory-use instrument intended for situational awareness only.
It is not TSO’d and should not be relied upon as a primary flight instrument.

 

10. Troubleshooting

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11. Warranty and Returns

All Radiant instruments carry a three-year warranty from invoice date.
Returns must be in new, uninstalled condition within 14 days of receipt.
Ship to: Radiant Technology Company, PO Box 20690, Wichita, KS 67208.
For support or warranty service, contact support@radiantinstruments.com.