New Fuel Gauge Features Are Here

We’ve updated the RADIANT RFGA GEN-2 Fuel Gauge family with new features designed to make installation, calibration, troubleshooting, and everyday fuel monitoring more useful for experimental, ultralight, and qualifying Light Sport aircraft.

The updated RFGA display shows fuel level as an analog-style dial, large digital percent, fuel quantity, and trend information, giving pilots a clearer view of both current fuel level and recent fuel-level behavior.

The RFGA family is offered in two versions: the RFGA Resistive Fuel Gauge for passive resistive senders connected to ground, and the RFGA 0–5V Capacitive Fuel Gauge for analog sender systems that provide a 0 to 5 volt output.

New Calibration System

One of the biggest improvements is the new calibration system. Each tank may now be calibrated using 2, 3, or 5 calibration points, allowing the gauge to better match the actual fuel tank and sender installed in your aircraft. For new installations, the 5-point calibration option is especially helpful because it can better account for tank shape and sender nonlinearity.

Supports Single or Dual Tanks

The updated RFGA also supports single-tank or dual-tank display modes, with fuel shown as an analog-style dial, large digital percent, and fuel quantity in the selected units. You can display fuel quantity in US gallons, liters, or imperial gallons, and each tank may have its own capacity setting.

Real-time sender troubleshooting

For troubleshooting and setup, the new RFGA provides more live sender information. The resistive version shows the sender resistance in real time and can indicate OPEN or SHORT sender fault conditions. The 0–5V Capacitive version shows the incoming sender voltage in real time and supports voltage curves that rise or fall with fuel level, as long as the calibration points form a valid curve.

Last-hour trend/history display

We’ve also updated the trend display. The RFGA now includes a companion graph showing fuel level over time, giving the pilot a better view of recent fuel-level behavior. This is especially useful for observing slosh, sender movement, and fuel-use trends. Fuel flow rate is computed from recent history and is advisory only; it is not calculated from a dedicated fuel-flow sender and should not be used for flight planning.

Other updates include internal 8-step brightness control from the front buttons, a simplified four-wire harness, support for +9 to +16 VDC aircraft power through a 1 amp fuse or breaker, and availability for both 2-1/4 inch and 3-1/8 inch panel installations.

The updated RFGA Fuel Gauges continue the RADIANT approach: compact, sunlight-readable instruments that give pilots useful information at a glance, with a setup process designed around the aircraft they actually fly.

New and updated features include:

• 2, 3, or 5-point calibration per tank

• Single-tank or dual-tank display modes

• Fuel quantity in US gallons, liters, or imperial gallons

• Separate capacity settings for each tank

• Real-time sender resistance display on resistive units

• OPEN and SHORT sender fault indications on resistive units

• Real-time sender voltage display on 0–5V Voltage units

• Support for rising or falling sender curves through calibration

• Last-hour fuel-level trend graphing

• Internal 8-step brightness control from the front buttons

• 2-1/4 inch and 3-1/8 inch panel versions

  
  

The RFGA is intended for experimental, ultralight, and qualifying Light Sport aircraft with manufacturer approval.

You can view the updated RFGA manual and product information on the GEN-2 Fuel Gauges page.

Radiant Fuel Gauges are available at Aircraft Spruce.