Solar Plane Lasts All Night Long

Swiss researchers yesterday marked a major milestone in the development of a solar-powered, single-pilot aircraft that they hope will eventually circumnavigate the globe. They kept their craft aloft through an entire night on stored solar energy.

In the wake of the event, the pilot, André Borschberg--CEO and cofounder of the Solar Impulse project--declared: "I have just flown more than 26 hours without using a drop of fuel and without causing any pollution!" The plane took off from a Swiss airbase early Wednesday and landed there at dawn Thursday.

Of course, it is a long way from this stunt to an aviation industry that isn't reliant on energy-dense jet fuel to hoist hundreds of thousands of pounds of cargo and passengers to cruising altitude. Unlike cars--which can today drive respectable distances on stored electrical energy--commercial aircraft will be dependent on liquid fuels for a long time.

But the Solar Impulse plane does include some novel engineering feats. Its wings are covered with 11,000 solar cells, and it uses lightweight composite structural parts and has a wingspan of 210 feet, not far from that of the world's biggest commercial jet, the Airbus A380, which has a wingspan of 260 feet. Keeping the plane's weight down to 3,500 pounds required optimizing electrical components in order to keep battery size as small as possible. The design was honed with computer modeling help from the European Space Agency and the Swiss Federal Institute of Technology. Still, the plane must fly at a pokey 28 miles per hour to save electricity. The lessons learned from the test flight will be used to develop an improved version of the plane that would attempt to fly around the world.

"It's good engineering, as you would expect from a Swiss team," said John Hansman, professor of aeronautics at MIT. But while the project is interesting, he says: "Solar will be a niche application for aircraft. It's hard to have enough energy capture to use for transportation, and solar cell efficiency is not high enough."

Despite their dubious commercial potential, lightweight solar-powered planes could be crucial to conducting long-term surveillance, and that's why various governments, including that of the United States, have been researching the technology. NASA's solar-powered Helios aircraft, one such unmanned effort, disintegrated due to turbulence during a 2003 test flight.

The unmanned solar powered record, set by QinetiQ's Zephyr UAV in 2008, stands at 82 hours 37 minutes or 3 1/2 days, exceeding the current official world record for unmanned flight which stands at 30 hours 24 minutes set by Global Hawk in 2001.

In 1999, the leader of the Solar Impulse project, Swiss adventurer Bertrand Piccard, became the first person (along with his copilot) to fly nonstop around the world in a balloon. "This is a highly symbolic moment," he said in a statement yesterday. "Flying by night using solely solar power is a stunning manifestation of the potential that clean technologies offer today to reduce the dependency of our society on fossil fuels."

Solar-powered Swiss plane gets its day in the sun (w/Video)

An experimental solar-powered plane whose Swiss makers hope someday to fly around the globe soared into uncharted territory Wednesday — the cold, dark night.

The team of adventurers and engineers behind the Solar Impulse project are already celebrating an aviation milestone for the longest solar flight after keeping the single-seat prototype aloft for almost 15 hours.

But with the goal of 24 hours of nonstop flight, the team set its sights on keeping the sleek aircraft with a 207-foot (63-meter) wingspan in the air until Thursday morning.

Pilot Andre Borschberg "will stay up there as long as possible," said Bertrand Piccard, the project's co-founder.

"Hopefully he will still be in the air at sunrise tomorrow. That is the challenge."
Borschberg took off from Payerne airfield into the clear blue sky shortly before 7 a.m. Wednesday, allowing the plane to soak up plenty of sunshine and fly in gentle loops over the Jura mountains west of the Swiss Alps.

As the sun set, technicians hoped the Solar Impulse's batteries — charged from the 12,000 solar cells fixed to the wings and body — would keep the four-engine plane engines airborne through the night. The batteries would begin charging again at dawn.
Earlier in the afternoon, Piccard told The Associated Press the flight was going "extremely well."

A record-breaking balloonist whose father and grandfather also accomplished pioneering airborne and submarine feats, Piccard has become the figurehead for the project and will be one of two pilots when it eventually takes off for its round-the-world attempt in 2013, with a scheduled five stops along the way.

Piccard said the night flight was a key step toward achieving that ultimate feat.
"The goal of the project is to have a solar-powered plane flying day and night without fuel," he said. "This flight is crucial for the credibility of the project."
At 9:30 p.m., Piccard told reporters that strong winds had pushed the plane off course, cutting the safety margin by one hour.

"If there is one hour missing tomorrow morning, it will be that hour," he said.
Should Borschberg or the team decide that it looks like the Solar Impulse won't make it through the night, the pilot will have the difficult task of landing the fragile aircraft before the batteries run out.

Borschberg was circling in Swiss airspace, first at 28,000 feet (8,535 meters) and then gently easing down through the night — always within gliding range of Payerne airport, so he can land if the plane runs out of energy, Piccard said. Still, the 57-year-old former Swiss fighter pilot is wearing a parachute — just in case.

Engineers in Payerne are closely monitoring every aspect of the aircraft, which has a thin fuselage and a wingspan of a Boeing 777 passenger jet. Its top speed is only 75 mph (120 kph) and it has no room for passengers or baggage, so it is as light and efficient as possible.

Piccard said the test flight — the third major step after its first "flea hop" and an extended flight earlier this year — will demonstrate whether the round-the-world trip is feasible.

The team had hoped to make its 24-hour test flight last week, when days in the northern hemisphere were even longer. But a problem with a key piece of communications equipment forced them to ground the plane while modifications were made.

Piccard, who achieved the first nonstop circumnavigation of the globe in a balloon, the Breitling Orbiter III, in 1999, said the next major step will be a solar Atlantic crossing. That will be done in a second, lighter prototype, because it will involve new challenges and dangers, he said.

Although the goal is to show that emissions-free air travel is possible, the team said it doesn't see solar technology replacing conventional jet propulsion any time soon. Instead, the project is designed to test and promote new energy-efficient technologies.

"Solar Impulse is a message as much as an airplane," he said.

Supersonic Green Machine

This future aircraft design concept for supersonic flight over land comes from a team led by the Lockheed Martin Corporation.

The only commercial supersonic aircraft to go into service, the Concorde, could only fly between New York and either Paris or London because most countries banning Concorde flights over land due to the sonic boom that constantly trails the aircraft at speeds above MACH 1.

The Lockheed team's simulation shows possibility for achieving overland flight by dramatically lowering the level of sonic booms through the use of an "inverted-V" engine-under wing configuration. Other revolutionary technologies help achieve range, payload and environmental goals.

One other major problem with the Concorde was that due to the enormous fuel consumption of the aircraft at MACH 2, the cost of a typical return transatlantic flight was around $24,000 - or the price of a new small car. To solve this problem we're wondering if either Boeing, Lockheed Martin or NASA are looking to resurect Project Pluto, a nuclear powered ramjet experiment from the 1960s or some of the aircraft reactor experiments (ARE) from the 1950s based on Molten-Salt Thorium Reactors.

This Lockheed Martin concept is one of two designs presented in April 2010 to the NASA Aeronautics Research Mission Directorate for its NASA Research Announcement-funded studies into advanced supersonic cruise aircraft that could enter service in the 2030-2035 timeframe.

EADS unveils four-engine electric aerobatic plane

EADS Innovation Works is casting its net wide in the search for solutions to aviation's environmental challenges. At the Green Aviation Show under way (June 18-22) in Le Bourget, Paris, EADS's research arm is presenting the first four-engined, all-electric aerobatic aircraft, based on the tiny Cri-Cri homebuilt.

Partnered by Aero Composites Saintonge and the Greencri-cri Association, EADS Innovation Works has presented Cri-Cri, the first-ever four-engined all-electric aerobatic plane, at the Green Aviation Show in Le Bourget from 18 to 22 June.

This aerobatic plane incorporates numerous innovative technologies such as lightweight composite structures that reduce the weight of the airframe and compensate for the additional weight of the batteries, four brushless electric motors with counter-rotating propellers which deliver propulsion without CO2 emissions and significantly lower noise compared to thermal propulsion, and high energy-density Lithium batteries.

The combined utilisation of these environment-friendly technical innovations enables the Cri-Cri to deliver novel performance values: 30 minutes of autonomous cruise flight at 110 km/h, 15 minutes of autonomous aerobatics at speeds reaching up to 250 km/h, and a climb rate of approximately 5.3 m/sec.

Set to undergo its first flight tests in the next few days, this four-engine electric plane paves the way for a new generation of environment-friendly high-performance aircraft.

Northrop Grumman wins contract to build US Army's long-endurance hybrid airship

A new hybrid airship weapons system, just larger than the length of a football field, will take to the skies in just 18 months to provide an unblinking, persistent eye for more than three weeks at a time to aid U.S. Army troops in Afghanistan, according to Northrop Grumman Corporation.

The company today announced it has been awarded a $517 million agreement to develop up to three Long Endurance Multi-Intelligence Vehicle (LEMV) systems for the U.S. Army. Northrop Grumman has designed a system with plug-and-play capability to readily integrate into the Army's existing common ground station command centers and ground troops in forward operating bases--the main objective to provide U.S. warfighters with persistent ISR capability to increase awareness of the ever changing battlefield.

"This opportunity leverages our longstanding leadership positions in developing innovative unmanned air vehicles, C4ISR weapon systems, and leading edge systems integration, and moves Northrop Grumman into this rapidly emerging market space of airships for the military and homeland defense arenas," said Gary Ervin, corporate vice president and president of Northrop Grumman Aerospace Systems sector.

Under the agreement, awarded by the U.S. Army Space and Missile Defense Command/Army Forces Strategic Command, Northrop Grumman will design, develop and test a long-duration hybrid airship system within an 18-month time period, and then transport the asset to the Middle East for military assessment.

"It is critical that our warfighters are equipped with more enabling integrated ISR capability to tackle today's and tomorrow's conflicts," said Alan Metzger, Northrop Grumman LEMV program manager. "Our offering supports the Army's Joint Military Utility Assessment that this disruptive innovation must meet the Army's objective of a persistent unblinking stare while providing increased operational utility to battlefield commanders. Part of our innovative offering includes open architecture design in the payload bay to allow sensor changes by service personnel in the field."

LEMV will sustain altitudes of 20,000 feet for a three-week period, and it will operate within national and international airspace. It will be forward-located to support extended geostationary operations from austere operating locations using beyond-line-of-sight command and control.

Northrop Grumman has teamed with Hybrid Air Vehicles, Ltd. of the United Kingdom using its HAV304 platform, Warwick Mills, ILC Dover, AAI Corporation, SAIC, and a team of technology leaders from 18 U.S. states to build LEMV. Northrop Grumman will provide system integration expertise and flight and ground control operations to safely take off and land the unmanned vehicle for worldwide operations.

Germany Firm Debuts Single Seater Electric Airplane

Calin Gologan, CEO of PC Aero introduced his Elektra One all-electric, single-seat airplane at Aero 2010 in Friedrichshafen, Germany. The 120 kg (264 lbs) composite airplane is powered by a 16 kW (peak) electric motor and has a operational endurance of up to 3 hours at 120 km/h. Its wingspan is 8.6 meters (28 ft) and it has an effective payload of 90 kg. (164 lbs).

It is designed to compete in the CAFE Green Flight Challenge in California this July. Partnering with NASA, the Challenge requires the aircraft to fly at least 100 miles per passenger on less than half a gallon of fuel or 17kWh of electric power at a minimum speed of 100 mph. The maximum range of the Elektra One is 400 km at 160 km/h.

PC Aero estimates that the all-electric airplane can fly up to 300 hours a year on the solar energy provided by just 20 square meters (215 sq ft) of solar panels, with an ROI of just eight years at current operating cost in Europe. It estimates flying clubs can operate Elektra One for €30 an hour.

DARPA's Solar Powered Radar Blimp to Hover 12 Miles over Future Battlefields

A high-altitude reconnaissance and surveillance platform, the Integrated Sensor Is the Structure (ISIS) is a tall order—literally. The unmanned airship, which measures 450 feet in length, will soar 70,000 feet above Earth for up to 10 years. It's not exactly the Goodyear blimp, and—in case you haven't guessed already—it's designed to cover more than the Super Bowl.

ISIS, like all blimps, is filled with helium, but comparisons end there. Hovering in the stratosphere, safely out of range of most surface-to-air or air-to-air missiles, ISIS is designed to provide unsurpassed situational awareness with a surveillance range of 187 miles for individuals on the ground and 373 miles for advanced cruise missiles.

From its parking space in the heavens, ISIS will have an excellent vantage point for surveillance and tracking. For example, objects on the ground can't disappear from the view of ISIS behind trees or mountains. "It's not just point coverage, like a view of a city," says Perry Hamlyn, head of MITRE's Advanced Wireless Electronics department. "You can see significant areas of an entire region."

As its name implies, ISIS features a highly creative design that takes the performance-to-mass ratio to a new level. In comparison with a conventional airship, in which the payload is two or three percent of the system mass, the ISIS payload will approach 30 percent.

An Unmanned Sensor Requiring Less Support

The system study for ISIS began in 2004 at the Defense Advanced Research Projects Agency (DARPA). In essence, ISIS offers more intelligence for less cost. "The whole idea behind ISIS is that the cost of the logistics is reduced considerably," says Weiqun Shi, a group leader in MITRE's Advanced Wireless Electronics division. "You don't have people in the air; you don't have multiple planes to keep an orbit going. Once you've launched an airship, it could be used 24 hours a day, seven days a week, with no humans on board. Think of it as an enormous, autonomous, unmanned sensor with years of persistence in surveillance and tracking of air and ground targets."

ISIS offers a compelling cost savings over existing reconnaissance aircraft that depend on forward-based logistics. At an airspeed of 60 knots sustained and 100 knots in a sprint, ISIS can deploy globally in 10 days from a permanent ground station in the continental United States. Current costs associated with reconnaissance—a local air base, multiple aircraft for a single mission, air crews, ground crews, fuel supplies, and maintenance facilities—will no longer be required.



New Designs for Enabling Technologies

To develop a stratospheric, airship-based, autonomous, unmanned sensor requires new technologies. The challenge for ISIS is to integrate an extremely lightweight, phased array radar into an airship platform. This involves three enabling technologies: the hull material, active-array antenna, and power system.

The hull material, which has significantly reduced fabric mass over the current state of the art, is a key design feature. It has to be stronger, lighter, and last 10 times longer than conventional hull material. This is a huge task.

Another distinguishing characteristic of ISIS is that the performance of its active-array antenna is based on size, not power. The exceedingly lofty height of ISIS allows the integrated airship-radar to use its aperture—not high power—to meet radar performance requirements. This approach, which exploits the platform's size and at the same time conforms to its limitations on weight and power, allows for the elimination of heavy high-power electronics. In addition, low-power transmit and receive modules based on low-cost "cell phone" technology contribute to the design requirements.

Energy generation and storage present another significant design challenge. ISIS includes novel power systems for the airship that are based on solar-regenerative power. Solar cells collect energy from the sun and create hydrogen and oxygen from water during the day. At night, the hydrogen and oxygen are recombined in the fuel cell, which releases energy that allows the airship to operate after dark. Fuel cells were chosen for energy storage since they offer the best mass-to-energy storage ratio when compared to batteries and other storage systems.

"We developed solar availability and system energy models, performed trade studies, and provided technical support to ISIS from the early concept phase all the way up to the current demonstration phase," says Hamlyn. "Throughout the program, we have been helping the contractors and the government ensure the technical feasibility of the project."

Testing Viability of the Total System

In its capacity as a manager of federally funded research and development centers, MITRE is able to play a critical role in working with the various contractors associated with the ISIS program. "We have been involved in all major technical challenge areas and have influenced the contractors toward viewing the viability of the total system, not just individual parts," says Shi. "For example we have tried to help all those working on ISIS understand how much power the whole system needs and the trade-offs associated with various options."

"Even though each subsystem—airship, radar, and energy generation and storage—is defined individually, we're helping the individual subsystem teams understand the complex interactions," adds Hamlyn. "All the systems have to react appropriately to each other in order to make the ISIS system possible."

The Air Force and DARPA have signed an agreement to develop a small demonstration prototype by 2014. Currently, ISIS is in phase three, which includes demo system design, large-scale integration, high-fidelity flight test simulation, demonstration system build, and flight demonstration. Much more remains to be done between now and the 2014 airship demonstration. "We are looking forward to seeing a revolutionary new ISR [intelligence, surveillance, and reconnaissance] capability for the future battlefield," says Hamlyn.

Electric Plasma Rocket Could Travel to Mars in 40 Days

Replacing chemical rockets with electric motors could cut the 6 month travel time between Earth and Mars by 75%. A company called Ad Astra has successfully tested a 200 Kw proto-type electro-magnetic thruster at full power and says a 20-megawatt engine could propel human missions to Mars in just 39 days.

A VAriable Specific Impulse Magnetoplasma Rocket (VASIMR) sometimes referred to as Electro-thermal Plasma Thruster or Electro-thermal Magnetoplasma Rocket, capable of reaching speeds of up to 126,000 miles per hour, uses radio waves to ionize and heat a gas such as argon, xenon, or hydrogen to 51.8 million degrees Fahrenheit (11 million degrees Celsius) contained and directed by a magnetic field to accelerate the resulting plasma and generate thrust.

We've had a look at Plasma Jet Engines possibly replacing fossil fueled jet turbines in commercial aircraft and it seems Plasma motors are the preferred option for NASAs future propulsion systems. Although a VASIMR is not suitable to launch payloads from the surface of the Earth due to its low thrust to weight ratio, they are well suited to act as an upper stage and can reduce the fuel requirements for in-space transportation, in some applications they are one-twentieth the cost of operating chemical rockets.

As with a Plasma Jet Engine, the electrical power source may be a challenge. As a station keeping motor on the International Space Station (ISS) the VASIMR could maintain the ISS's orbit without requiring any additional fuel as the motor would be powered by the Stations solar panels and use hydrogen as the propellant gas which is already generated as a waste product on the Station.

While the 200-kilowatt prototype VASIMR engine will suffice for ISS station keeping, the distance between the Earth and Mars varies between 35 and 250 million miles (55 million and 400 million kilometers) depending on their points of orbit, so a 20-megawatt plasma rocket is required for a human flight to Mars. Solar isn't really an option at these power levels. The entire solar array on the ISS generates 120 kW. Using Solar to generate 20 MW would require an array 160 times the size and it would produce less energy as the spacecraft traveled further away from the sun so the only option is a Nuclear power source.

The VASIMR is expected to be put to work on the ISS for orbit re-boosting duty in late 2013 or early 2014.

Ad Astra Rocket Company

Solar-powered UAV could aid Australia fire monitoring

Queensland University of Technology is aiming to have a lightweight, hand-launched, solar-powered unmanned air vehicle commercially available within 24 months following successful flight tests.

The Green Falcon solar UAV, which can provide 24h service without fuel or pollution, is particularly targeted at emergency services. Other potential applications include coastal and border surveillance; atmospheric and weather research and prediction; environmental, forestry, agricultural and oceanic monitoring; and imaging for the media and real estate industries.

Another possibility is monitoring fires. "Bush fires in Australia have killed many people and caused millions of dollars in damage. The Green Falcon is a next-generation warning system with remote sensing and visual data capability," says the university's aerospace avionics engineer Dr Felipe Gonzalez.

The UAV has a 2.5m (8.2ft) wingspan and weighs 4kg (8.8lb) without a payload and 5kg with. It is powered by 28 advanced highly efficient monocrystalline solar cells and features a maximum power point tracker, a purpose-built energy management system and an efficient lithium-ion battery, says Gonzalez.

Unlike other solar UAVs that have been developed, Gonzalez says the Green Falcon is cost-effective and easy to launch with minimum maintenance requirements. "The Green Falcon is lightweight, it can be hand-launched and costs are low compared with other UAVs available today," he says.

The design supports improved swarming capabilities compared with other UAVs, says Gonzalez, which will allow the Green Falcon to provide coverage over large areas in as short a time possible, particularly useful in rescue or fire monitoring missions.

The Green Falcon performed its maiden flight in June. Work is currently focused on optimal flightpath planning ahead of the next flight-test campaign at the Australian Research Centre for Aerospace Automation/Queensland University of Technology's flight-test range facility near Kingaroy, Queensland.

To take the project further, including testing the methodology for continuous flying, funding in the region of A$50,000-80,000 ($45,000-75,000) is required or support in the areas of electronics, manufacturing and advanced wireless cameras, says Gonzalez.

Ultra-Light Mosquito Electric Helicopter Can Even Fly in Caves

The electrically powered ultra-lightweight mosquito helicopter concept has been designed for army to commute through difficult terrains like canyons, forests and even caves.

This flying object is empowered with four GEMINI technology based powerful electric motor and contains carbon nanotube super-capacitors that provides the energy to run the motors.

When the pilot triggers the helicopter, the integrated computer controls the stability and levitation of the helicopter and to rotate it left, right, backward, forward, up and down, the driver has to lever his both hands to shift the helicopter in the preferred direction.

However, the concept is not able to generate a high speed, but its silent operation and excellent steering capability can make it a very functional. In case of any danger, the computer will activate the emergency landing program automatically.

Yuneec e430 Electric Plane To Ship in 2011

The Yuneec E430 is a twin seat, single engine, LSA class aircraft designed to be simple to use, easy to fly and with virtually zero vibration, it's very smooth. Because it's an EV it has low noise, no emissions, no fuel and with only 2 moving parts in the motor (the bearings) the reliability and maintenance are like nothing seen before.

Yuneec say the e430 will be ready for sale next year. If the company delivers on its promise, this electrically powered plane could change the world, costing just two dollars per hour to power its flight.

The first planes will cost $89,000. That's not too bad as far as private planes go. If its whisper-quiet engine is too loud for you (or if you've run out of power during its 1.5- to 3-hour flight time), the plane's 25:1 glide ratio will give you plenty of time to find a place to land or can extend the aircraft's range by combining powered and glider flight.

NASA Designs a One-Man Electric VTOL Stealth Plane

A super-quiet, hover-capable aircraft design, NASA's experimental one-man Puffin could show just how much electric propulsion can transform our ideas of flight. It looks like nothing less than a flying suit or a jet pack with a cockpit.

On the ground, the Puffin is designed to stand on its tail, which splits into four legs to help serve as landing gear. As a pilot prepares to take off, flaps on the wings would tilt to deflect air from the 2.3-meter-wide propeller rotors upward, keeping the plane on the ground until it was ready to fly and preventing errant gusts from tipping it over. The Puffin would rise, hover and then lean over to fly horizontally, with the pilot lying prone as if in a glider. When landing, the extending spring legs would support the 3.7-meter-long, 4.1-meter-wingspan craft, which is designed with carbon-fiber composites to weigh in at 135 kilograms, not including 45 kilograms of rechargeable lithium phosphate batteries.

In principle, the Puffin can cruise at 240 kilometers per hour and dash at more than 480 kph. It has no flight ceiling—it is not air-breathing like gas engines are, and thus is not limited by thin air—so it could go up to about 9,150 meters before its energy runs low enough to drive it to descend. With current state-of-the-art batteries, it has a range of just 80 kilometers if cruising, "but many researchers are proposing a tripling of current battery energy densities in the next five to seven years, so we could see a range of 240 to 320 kilometers by 2017," says researcher Mark Moore, an aerospace engineer at NASA's Langley Research Center in Hampton, Va. He and his colleagues will officially unveil the Puffin design on January 20 at an American Helicopter Society meeting in San Francisco.

Moore and his colleagues at NASA, the Massachusetts Institute of Technology, the Georgia Institute of Technology, the National Institute of Aerospace, and M-DOT Aerospace named their craft the Puffin because "if you've ever seen a puffin on the ground, it looks very awkward, with wings too small to fly, and that's exactly what our vehicle looks like," he explains. "But it's also apparently called the most environmentally friendly bird, because it hides its poop, and we're environmentally friendly because we have essentially no emissions. Also, puffins tend to live in solitude, only ever coming together on land to mate, and ours is a one-person vehicle."

This design relies on electric motors. These remain efficient regardless of their size, whereas internal combustion engines become less efficient the smaller they are. As such, electric aircraft can use small motors while generating impressive propulsion—the Puffin can lift a person with just 60 horsepower.

At up to 95 percent efficiency, electric motors are far more efficient than internal combustion engines, which only rate some 18 to 23 percent. This means electric aircraft are much quieter than regular planes—at some 150 meters, it is as loud as 50 decibels, or roughly the volume of a conversation, making it roughly 10 times quieter than current low-noise helicopters.

This super-quiet quality makes the Puffin potentially ideal for covert military insertions of special operations units and other troops—indeed, it was originally aimed to launch from submarines; unmanned versions could also help transport supplies. Quieter aircraft also mean that airports for civil applications such as personal travel and fast courier services could be located much closer to population centers and perhaps even residences without bothering others, significantly cutting down commute times. Inventors all over the world are still striving to develop personal air vehicles, the equivalent of a plane in every garage—for instance, Samson Motorworks is trying to develop a land/air-capable motorcycle.

In addition, since electric motors are so efficient, they also generate far less heat. This not only gives them a lower thermal signature for military stealth, but means they don't need anywhere near the same amount of cooling air flowing over them that internal combustion engines do, thereby reducing aerodynamic drag that can slow them down.

Because electric motors have fewer moving parts, they are perhaps 10 or even 20 times more reliable than piston engines. In addition, the Puffin's design allows pieces of either of its two electric motors to fail without any reduction in power to the prop rotors. The plane could also take a hard, forceful landing if necessary, as the landing gear supports the brunt of the load instead of the pilot, unlike some other one-man flying craft.

"The Puffin is an exciting idea.... It converges and demonstrates many technologies at once," said Brien Seeley, president of the Comparative Aircraft Flight Efficiency (CAFE) Foundation, a Santa Rosa, Calif.–based independent flight test agency that hosts the annual Electric Aircraft Symposium. "In my opinion, a mass-marketable version will need conventional seating, cup holders and a short runway for glide-in, view-ahead landings—but opening up people's imagination is the first essential step."

By March, the researchers plan on finishing a one third–size, hover-capable Puffin demonstrator, and in the three months following that they will begin investigating how well it transitions from cruise to hover flight. They are already looking past the Puffin, however. The next-generation of this design might incorporate more than just two pairs of prop rotors, so that if one was struck by, say, a bird or gunfire, the aircraft could survive on redundant systems. "We could make it so there's no single point of failure—that's the cool next step," Moore says.

Korea University plan solar-powered UAV

An ambitious project has been launched to develop an ultra high-altitude solar powered unmanned aerial vehicle (UAV) - which can hover at an altitude of 20 km for several months. On January 7, Korea Aerospace University (KAU) and the Korea Institute of Science and Technology (KIST) signed a memorandum of understanding (MoU) on developing a solar-powered unmanned aerial vehicle. The MoU came to push ahead with a plan to create a solar-powered drone by merging the KAU's design technology for mid-altitude unmanned aerial vehicles with KIST's solar cell power generation technology.

At the end of last month, KIST had already inked a MoU with Korea Aerospace Research Institute (KARI) to develop unmanned aerial vehicles. The KAU and KIST plan on ultimately developing an unmanned aerial vehicle with 40m-long wings, to which solar cells are attached to power the motor-operated propeller. At night, electricity stored on the lithium-ion battery will come into play to help the drone stay at high altitudes.

By 2012, a prototype UAV with 4m-long wings is expected to be flown on a pilot run, and a UAV, 10 times the size of the prototype UAV, will emerge by the second half of 2010. Officials from KIST and the KAU have set their first goal of a 48-hour non-stop flight. Since solar powered UAVs- effectively used for aerial surveillance over a vast geographic area around the clock for 364 days- have strategic military value, NASA (the United States space agency), the UK and Germany are keen on developing ultra high altitude drones.

NASA developed "Helios", a solar-powered UAV which was designed to fly in the stratosphere, but it fell down from an altitude of 8,000m and crashed during its test flight in 2003.

Electric Fuel Cell UAV Sets Unofficial Endurance Record

The Naval Research Laboratory's (NRL's) Ion Tiger, a hydrogen-powered fuel cell unmanned air vehicle (UAV), has flown 23 hours and 17 minutes, setting an unofficial flight endurance record for a fuel-cell powered flight. The test flight took place on October 9th through 10th at Aberdeen Proving Ground. The Ion Tiger fuel cell development system team is led by NRL and includes Protonex Technology Corporation, the University of Hawaii, and HyperComp Engineering. The program is sponsored by the Office of Naval Research (ONR).

The electric fuel cell propulsion system onboard the Ion Tiger has the low noise and signature of a battery-powered UAV, while taking advantage of hydrogen, a high-energy fuel. Fuel cells create an electrical current when they convert hydrogen and oxygen into water, with only water and heat as byproducts. The 550-Watt (0.75 horsepower) fuel cell onboard the Ion Tiger has about 4 times the efficiency of a comparable internal combustion engine and the system provides 7 times the energy in the equivalent weight of batteries. The Ion Tiger weighs approximately 37 pounds and carries a 4 to 5 pound payload.

Small UAVs are growing in importance for naval missions, as they provide capabilities ranging from surveillance collection to communication links. Electric UAVs have the additional feature of being nearly undetectable from the ground. Due to the high energy in the fuel cell system onboard the Ion Tiger, it is now possible to do long endurance missions with an electric UAV, thus allowing a larger cruise range and reducing the number of daily launches and landings. This provides more capability while saving time and effort for the crew.

In 2005, NRL backed initial research in fuel cell technologies for UAVs. Today, says NRL's Karen Swider-Lyons, "the long endurance flight was made possible by the team's research on high power, efficient fuel cell systems, lightweight hydrogen-gas storage tanks, improved thermal management, and the effective integration of these systems."

Fuel cell technology is being developed to impact the operational spectrum of technologies including ground, air and undersea vehicles and man-portable power for Marine expeditionary missions. "The Ion Tiger successfully demonstrates ONR's vision to show how efficient, clean technology can be used to improve the warfighter's capabilities," comments ONR's Michele Anderson.