Air Force SBIR – Enabling Technologies – Baker Micro CI Fuel Injection System

The US DoD has been driving towards the Single Fuel Concept for decades with the goal of using JP8 or F24 kerosene-based products for all ground and air vehicles. Implementation of a single fuel has been challenging for small engine applications such as generators and particularly small, unmanned aircraft applications.

Red flag


Fuel system components are not commercially available for very small compression ignition heavy fuel engines. Small heavy fuel engines have instead been limited to low compression spark ignited operation resulting in drastically lower power density than either spark ignited gasoline engines or compression ignition heavy fuel engines.
SBIR Case Study
Solution Icon


Baker Engineering approached the need for small scale fuel system components for compression ignition heavy fuel engines from multiple directions over the course of several consecutive SBIR efforts for diverse DoD customers including US Navy, US Airforce and US Army, ultimately developing a compact common rail fuel system and demonstrating the system on several engines from 28 cc to 400 cc per combustion chamber.

The Micro CI fuel system consists of the Micro CI injector, the Micro CI pump, a passively regulated common fuel rail, and an engine integrated pump drive.

The Micro CI injector is a solenoid actuated common rail diesel injector with reduced body length, flow optimized for engines of 2-35 hp per combustion chamber, and application specific needle travel and spray geometry.

The Micro CI pump, currently available in two capacities can be operated up to 1000 bar fuel pressure and up to 7500 cycles/min depending on application requirements. In most small engine applications, the Micro CI pump is paired with a single injector.

Fuel pressure in the Micro CI fuel system is passively controlled by a bypass fuel pressure regulator integrated into the compact common fuel rail. Active control can also be achieved through metering of the pump inlet by inlet pressure or by an inlet metering valve depending on desired system complexity and weight requirements.

Baker Engineering continues to improve the system, most recently developing internal capabilities for measurement of injector flow to create injector calibration data sets for use in engine calibration.

  • Micro high pressure fuel pump and drive
  • Compact passively regulated fuel rail
  • Compact solenoid actuated common rail injectors
  • Engine integrated pump drive

View More Case Studies

Enabling Technologies Baker Case Study

Air Force Phase II SBIR – Enabling Technologies – Baker Light Weight Dry Sump System

  • U.S. Air Force
  • U.S. Army
  • U.S. Navy
To support the addition of an oil lubricated turbocharger and fuel pump drive on the Baker Heavy Fuel Rotary Engine, a compact, lightweight dry sump oil system was developed.

U.S. Army Phase II SBIR – Stryker – Opposed Piston APU

  • U.S. Army
Baker Engineering developed our single cylinder opposed piston engine into a complete APU package with integrated support systems in the front sponson of the Stryker vehicle.
Tigershark Case Study

Air Force Phase II SBIR – Tigershark UAV Baker Heavy Fuel Rotary Demonstrator – Flight Test

  • U.S. Air Force
As part of an Air Force Research Lab (AFRL) SBIR contract, Baker Engineering developed a turbocharged direct injected heavy fuel rotary engine in flight tests.

Connect With an Engineer

Whether you have a government or private project, connecting with an experienced Baker engineer is an excellent way to ensure that your technical requirements are understood.

Reach out to us, and we will set a meeting between your team and one of our qualified engineers, who can answer your questions.

"*" indicates required fields

This field is for validation purposes and should be left unchanged.