Wolverine UAS engine

Ricardo today announced that it is developing a new purpose-built family of unmanned aerial vehicle (UAV) engines called Wolverine for both civilian and military applications.

The first engine in the family – the Ricardo Wolverine 3 – is designed to power lightweight aircraft and use military-spec heavy fuels. It is a 3.1-horsepower, two-cylinder, two-stroke, air-cooled engine with spark ignition, direct fuel injection and 500 watts of on-board power, thanks to an integrated starter-generator. Ricardo is studying plans to develop Wolverine engines to power UAVs with heavier payload and greater range and endurance requirements.

“UAVs are extremely versatile and give our soldiers tactical and operational advantages on the battlefield. That’s why the Pentagon’s investment in UAVs has more than doubled to $4 billion since 2006,” said Kent Niederhofer, president of Ricardo’s North American subsidiary Ricardo, Inc. “In addition, UAVs are becoming an increasingly valuable tool for border protection, drug interdiction, fire-fighting and more. Whatever the mission, Ricardo will engineer Wolverine engines that are far more capable and vastly more reliable than what’s in use today.”

Engineers at Ricardo’s Detroit Technology Campus in Van Buren Township have taken the Wolverine 3 from concept to production readiness in six months, and they successfully completed the engine’s “first fire” on a dynamometer test stand in early May. Next, the Wolverine 3 will be installed in a small tactical UAV in preparation for its first flight, which is scheduled for summer 2010 at the Nevada test site. Ricardo is currently in talks with over a dozen UAV integrators about putting the engine into series production.

Ricardo’s lightweight, heavy-fuel solution
Over the last decade, military UAVs have been developed to carry out a wide range of missions, from surveillance to heavy-ordnance delivery. Since 2006, the U.S. military’s UAV operations have grown from about 165,000 hours to more than 550,000 hours annually, according to the U.S. Department of Defense. Today, the U.S. Air Force actually trains more unmanned than manned aircraft pilots.

According to Dr. Ron Storm, director, military market development at Ricardo Inc., smaller UAVs routinely carry multimillion-dollar systems of cameras, sensors and other electronics, but are typically powered by gasoline engines originally designed for lawn and garden equipment, or model planes. “Today, the engine is the weak link in the UAV system, especially in these smaller aircraft,” said Storm. “The military and aircraft integrators worked with off-the-shelf engines and adapted them for UAVs so they could deploy the technology to war fighters rapidly. However, the engines weren’t designed as part of a complete system around the needs of soldiers in the field, so failures have been unacceptably high.”

To understand the specific needs of UAV customers and pilots, Ricardo worked with military and civilian experts, including Rick Scudder, director of the University of Dayton (Ohio) Research Institute’s Center for UAV Exploitation, and Larrell Walters, director of the University of Dayton-led Institute for Development and Commercialization of Advanced Sensors Technology.

“This program has been an exciting collaboration,” said Stephen Cakebread, Ricardo Inc. project director, unmanned systems, and architect of the Wolverine 3. “As we learned more from people with hands-on UAV development and in-field experience, we realized that an engine that isn’t purpose-built for aviation is going to be inherently compromised from the standpoint of performance, weight, package efficiency and durability.”

In particular, relying on gasoline creates logistical and reliability problems in the field, Ricardo learned.

“Most military vehicles and stationary power sources use heavy fuels, so gasoline is often shipped in at enormous expense or sourced locally, which means that octane and purity levels can vary widely,” said Ricardo’s Tom Howell, chief engineer. “It’s not uncommon for engines to fail after only a few hours of service, and poor fuel quality is often the culprit. Our heavy-fuel design will help reduce these costly failures that put lives at risk.”

Ends

Key specifications of the Wolverine 3:

Configuration: 2-Cylinder
Cycle: 2-Stroke
Cooling: Air
Power: 3.1hp/2.3kW
Displacement 5.37cu in/88cc
Max. Speed 6,000 rev/min
Ignition: Spark
Fuel Injection: Direct
Starting: Starter Generator 500W
Width: 10.5″ / 267mm
Height 6.9″ / 175mm
Length 7.6″ / 193mm

Gary Mortimer

Founder and Editor of sUAS News | Gary Mortimer has been a commercial balloon pilot for 25 years and also flies full-size helicopters. Prior to that, he made tea and coffee in air traffic control towers across the UK as a member of the Royal Air Force.