Suivre ce blog Administration + Créer mon blog
19 mars 2015 4 19 /03 /mars /2015 17:20
Concept design for the SilentHawk hybrid-electric motorcycle - Logos Technlogies

Concept design for the SilentHawk hybrid-electric motorcycle - Logos Technlogies


March 19, 2015: Strategy Page


U.S. SOCOM (Special Operations Command) is testing a SilentHawk hybrid-electric motorcycle for troops to use in places where lightweight transportation is needed, especially in areas (like Afghanistan and Iraq) where roads may be risky because of roadside bombs and mines.


Some countries have already used conventional motorcycles with some success, but found that the noise a conventional motor generates was sometimes a problem. The SilentHawk has a max range of 370 kilometers (170 miles) but can run silent (on just batteries) for up to 80 kilometers. Weighing 149 kg (350 pounds) SilentHawk can also carry 34 kg (75 pounds) of cargo. While based on a commercial bile (RedShift), SOCOM is testing to see if the militarized version is rugged and reliable for battlefield use. SOCOM has tested all-electric bikes before but those did not have the range required for combat use. Despite that SilentHawk is designed so the gasoline motor can be easily removed providing a shorter (and a bit lighter) range all-electric bike.


Despite the noise factor British special operations troops used a militarized versions of the Yamaha Grizzly 450 in Afghanistan. Basically the Grizzly is a four wheel, 285 kg (628 pound) cross country motorcycle. This ATV (all-terrain vehicles) is 2.73 meters (six feet) long and 1.1 meters (3.5 feet) wide. In addition to the driver, there are racks on the bike that can carry another 80 kg (175 pounds). Grizzly can tow a trailer carrying another 159 kg (350 pounds) of cargo. Top speed, on a flat surface, without a trailer, is about 75 kilometers an hour. Cross country, it's usually about half that and a bit less if a trailer is being hauled. The British Army bought 250 Grizzly 450s in 2005, and these were very popular with the troops in Afghanistan. There they are used for patrolling and hauling supplies to troops in isolated positions. The British paid $41,000 for each bike, although that includes a trailer, spare parts, and technical services. The civilian version goes for about $8,000 each.


MV850 ATV photo Polaris  Industries Inc

MV850 ATV photo Polaris Industries Inc


ATVs have proved particularly useful, and popular, in Afghanistan, especially for special operations forces. There are many models in use, all of them militarized civilian vehicles. These vehicles are innovative both in original concept and how they are constantly modified and upgraded. One useful innovation was the use of non-pneumatic tires. This first showed up as optional equipment for the MV850 ATV. This is an 800 kg (1,800 pound) 4x4 vehicle with the largest cargo carrying capacity (385 kg/850 pounds) of any vehicle in its class. It is a compact vehicle at 242.3x120.1x152.4cm (94.5x47.3x60 inches). It can also haul a trailer carrying 680 kg (1,500 pounds). Top speed is 83 kilometers an hour.  The non-pneumatic tires are not solid like traditional tires but built with a web of plastic honeycomb and surrounded by a thick band of rubber that is very similar to the tread found on pneumatic tires. These tires can survive a hit by a 12.7mm (.50 caliber) bullet and keep going. They feel about the same as pneumatic tires, although some users report they are not as effective in mud or watery surfaces.


The U.S. Department of Defense has been buying ATVs (as well as motorcycles) for American troops in Afghanistan since 2004. One of the more popular models was the Ranger, which is a militarized ATV that is 2.9 meters (nine feet) long, 1.6 meters (five feet) wide, weighs 760 kg, and can carry nearly as much. There are two seats and a rear deck that can hold up to half a ton of cargo. The top speed of 67 kilometers an hour and the ability to ford 76 cm (30 inches) of water contributes to excellent cross country performance. A 49 liter (13 gallon) fuel tank gives the Ranger a range of 500 kilometers or more, depending on how much time is spent off-roads. The Ranger engine burns military JP8 fuel and generates 40 horsepower. The Ranger began arriving in Afghanistan and Iraq in 2006, initially for use by light infantry and commandos. Troop reaction was positive. SOCOM has long been a user of various ATVs. Eventually, regular army units got the ATVs, mostly for hauling gear around remote outposts. ATVs could be flown in slung under a helicopter. The ATVs were often used to collect air dropped supplies that, because of the often unpredictable winds, fell far from the base.


The ATVs have been so popular that many troops have bought them when they get back home and use them for cross-country trips (for camping, hunting, or just sightseeing). The army has bought some of these ATVs for use by troops just returned from Iraq or Afghanistan. It's the kind of high-excitement recreation that has been found to help the troops decompress after returning from a combat tour.

Partager cet article
18 mars 2015 3 18 /03 /mars /2015 08:20
Concept design for the SilentHawk hybrid-electric motorcycle - photo Logos Technlogies

Concept design for the SilentHawk hybrid-electric motorcycle - photo Logos Technlogies


March 16, 2015 By Joe Gould – Defense News


WASHINGTON — Picture a small team of US special operators racing quietly through the night on stealth motorcycles, cruising over rugged terrain to catch enemy fighters completely unawares.


That is the scenario Virginia-based Logos Technologies envisions as it develops its hybrid-electric motorcycle SilentHawk on behalf of a Defense Advanced Research Projects Agency (DARPA) project started in 2014. Logos, teamed with Alta Motors, is developing a prototype for their phase II Small Business Innovation Research award from DARPA.


Once the prototyping phase is complete, the next phase could see the military replace motorcycles in service, such as the Kawasaki M1030 M1. DARPA anticipates Marines, soldiers and special operations forces will buy it, and there could also be a substantial commercial market.


Logos' hybrid-electric propulsion system, originally designed for an unmanned aircraft, is integrated into Alta Motors' RedShift MX electric motocross bike. Logos is also known for its Kestrel wide-area persistent surveillance system, used by the US military in Afghanistan.


The quiet, all-wheel drive bike would run on an all-electric motor, gasoline or JP-8. Its total range is intended to be 120 miles on fuel and 50 miles on the battery or silent mode, and it would maintain speeds above 50 mph for long distances, on a flat dirt road.


Developers envision a small special operations team being dropped off by a small helicopter or V-22 Osprey, then closing with their target in the bike's silent mode. They might take the target and stealthily rendezvous at a second landing zone.


From an outpost in Afghanistan, for instance, the bikes could be used to avoid predictable routes and evade ambushes by traveling though woods or terrain that would be impassible in a four-wheel vehicle.


"You're trying to create uncertainty for the enemy about your location, and you make it difficult for them by being quiet, or by them being unable to determine where you are, especially when you operate at night," said Wade Pulliam, manager of advanced concepts for Logos Technologies.


The bike's combustion engine would be loud as 75 decibels, but in silent mode, would have to operate at 55 decibels — considered a stretch goal, Pulliam said.


Having an engine that is powerful, yet compact enough to fit on the bike, with a battery, was a challenge. The Alta battery pack itself is compact at 180 watt-hours per kilogram, which is comparable to a laptop battery, and still rugged.


The key to the design is that the bike's hybrid-electric unit fits under the seat and can be attached or detached from the rest of the bike in 30 minutes. That allows operators in the field to swap from a hybrid-electric version to electric-only version for short-range, all-silent missions.


The team tested regenerative braking, meaning it converts its kinetic energy to charge the battery, a boon on rough terrain, when braking is frequent. In the design phase, it was tested on the real wheel, but with an all-wheel drive prototype, Pulliam expects to see an improvement.


"In off-road conditions you see a real benefit," he said.

Partager cet article


  • : RP Defense
  • : Web review defence industry - Revue du web industrie de défense - company information - news in France, Europe and elsewhere ...
  • Contact


Articles Récents