Fuel Level Alert System Aboard F-5 jets is 'unsafe,' Navy says

If you’ve spent any time around the cockpit of an F-5 Tiger, you know that situational awareness is everything.

While the F-5 jet is a legendary adversary platform, the current fuel monitoring system leaves a bit to be desired. Right now, pilots are only alerted to low fuel when they hit the 350-410 lbs threshold—a stage that the Navy identifies as an “unsafe condition.” The Naval Air Systems Command (NAVAIR) is looking to change that and is turning to industry for help.

The Mission: Upgrading the F-5 Fuel Interface

NAVAIR’s PMA-226 recently issued a Sources Sought notice to identify potential solutions for a custom fuel alert system for both the single-seat F-5N and the dual-seat F-5F. The fuel level alert system is also known as “Bingo” or “Joker” fuel bugs.

The goal is to enable pilots to configure, set, and activate mission-specific fuel alerts during pre-flight. By allowing aircrew to dial in their custom thresholds, they can better manage their energy state throughout a sortie, rather than relying solely on a low-fuel warning light.

What the Government is Looking For

NAVAIR is prioritizing Commercial Off-The-Shelf (COTS) solutions. The goal is to minimize non-recurring engineering (NRE) costs and development time by utilizing tech that is already designed and qualified for F-5 configurations.

Here are the key performance requirements NAVAIR is seeking:

• Fuel Monitoring: Real-time tracking of fuel levels (0-2,500 lbs) via the existing capacitance signal system.
• Custom Thresholds: The ability to set "Bingo" and "Joker" levels in 100 lb increments.
• Ergonomics: Easy, tactile adjustments (like a knob) that allow pilots to adjust levels in-flight or pre-flight.
• Form Factor: If the solution requires replacing the current fuel indicator (part number 14-64900-9), the new unit must be the same size and weight to ensure seamless integration.

The Timeline at a Glance

NAVAIR has laid out an ambitious but defined schedule for this project:

• NRE Period: Max 18 months from award.
• Airworthiness Approval: Max 4 months post-validation.
• Quantity: An initial request for 15 units.

This is a market research effort, not a formal request for proposals, but it’s a vital step for companies looking to be part of the F-5 program's future. Companies have until June 8 to respond and support the work.

The F-5 was developed by Northrop Grumman in February 1965. Today, the fleet is primarily used as adversary aircraft for training. The fleet is managed by NAVAIR’s Adversary and Specialized Aircraft Program Office (PMA-226).