The US special forces are about to be equipped with stealth locusts

Light weight, made for fast and rugged terrain, locomotives allow special forces to cross the forest, squeeze between narrow canyons, through alleys . But that dusty motorbike really very noisy, so any secret mission is revealed by the roar of the engine.

That's why DARPA, the US Department of Defense's future research and development agency, is funding a project to develop electric locomotives so that task forces can run the car smoothly. may. The car was called "SilentHawk" (silent falcon) and after receiving the first prototype, DARPA was too satisfied with the request so it ordered two more.

SilentHawk is the result of a partnership between Logos Technologies, which produces military tools such as drones and sensors, and Alta Motors, the manufacturer of locomotives.

Creating a noise-free motorcycle means starting from an electric car. By design, a modified version of SilentHawk will use a hybrid engine, so it can run on gasoline for most of the time, and power when it needs to be quiet. And this car not only limits fuel to gasoline, it also runs diesel as well as jet fuel JP5 and JP8. Therefore the task force using this vehicle on the battlefield can load any fuel they have. When powered by fuel, SilentHawk charges itself and any electronic device that the soldiers have, such as a radio, GPS or tablet signal receiver.

SilentHawk can also run on jet fuel.

"Because they are motorcycles and they are quite small, you can put some of these cars on the back of a V-22 plane and they can be dropped anywhere , " said Doug Rombough, Vice Chairman of Logos Technologies said. "They can run 50 miles (more than 80km) and when they reach about 10 miles (16km) from the subject, the driver can turn off the multi-fuel engine for electric driving - and the only noise arises. That time will be the noise of the wheels on the surface or the chain of the car ".

When running fuel with the generator activated, the car emits about 75 decibels of noise. Switching to all electrics, SilentHawk chief development engineer Alex Dzwill said that it produced no more than 55 decibels of noise, or the sound of normal conversation. Can it make it quieter?

"The thing that makes the most noise is the chain and we can equip it with a belt, even though there are dozens of reasons why you don't want a belt on a locomotive, " Dzwill said. "If you go on a rocky road, you will remove that belt, but if you are on a sandy terrain like a desert, you may use the belt and it is very good."

SilentHawk has a maximum speed of 80 mph when running on electric motors or hybrid engines.

Therefore, 55 decibels is probably the quietest noise that such a scratch car can achieve. The rickshaws are regulated to produce noise levels below 113 decibels, so compared to howling engines often come with scratchy cars SilentHawk is a significant improvement.

The car was so smooth that it was the designer who was surprised. Mr. Dzwill recalled an experiment in the forest, where a driver could sneak in without him noticing."He jumped up from behind us, like our sound was walking, just enough to completely hide the sound of the approaching motorcycle behind us , " he said. For comparison, you can hear a gasoline-powered locomotive up to a mile away.

Other invisibility SilentHawk besides the engine runs smoothly, but that may be enough for a professional soldier to run it into the battlefield. Moving without being detected is a huge advantage, making the vehicle not a barrier to soldiers. That meets one of DARPA's goals when it comes to creating new models: weight reduction while retaining all the additional features.

Other factors include a 270-pound Alta Motors electric motor (122kg). With many other things added to the first prototype, including two rudders, hybrid engines and control systems, the car weighs 350 pounds (159kg).

SilentHawk.

To reduce that weight, Logos will need to work again on the hybrid engine. Originally built for the Parahawk unmanned transport program, this engine is liquid-cooled. An air-cooled engine may reduce the overall vehicle weight.

And to create flexibility and lighten the vehicle's load, SilentHawk is modular. A kit will provide auxiliary power, a user interface and device storage. Another set will expand the range of the vehicle. Both kits can operate with seat-mounted hybrid and saddle engines that can be commutated for a standard saddle. (Generator can also operate even if the car is not running). The ultimate goal is something versatile for many needs to be able to fit into the battlefield.

"You can turn a hybrid motorbike into an electric car, in about 30 minutes or maybe an hour if you don't have the experience to do it," said Rombough, vice president of Logos Technologies. "You can swap the engine back and forth if you want a lighter motorcycle for your upcoming mission."

These prototype cars will be produced within 1 year. If DARPA wants to, the next stage will be to produce a terrain motorcycle that task forces can move wherever they want without being detected.