New Fasteners which works as Crack Sensor

    Alcoa is developing aircraft fasteners with Sanford researchers that also function as sensors capable of detecting crack propagation in multilayer composite structures

The technology could reduce inspection frequencies for wing stringers by one-half. Fatigue cracks forming at fastener holes are a common form of airframe damage.

How it works?

   In the invention, a fastener couples layers of a multi-layer structure together via an opening that traverses the structure. A sensor circuit is inserted into the opening with the fastener, inducing an electrical response in a portion of the multi-layer structure adjacent to the opening. If the structure surrounding the fastener hole is damaged, the electrical response is slowed, indicating a failure.

In one example of the technology, a sensor film is embedded on the shank of an aircraft fastener, such as a 1.5 inch shank fastener from Alcoa Fastening Systems. An eddy current is applied to the sensor. The sensor's circuit is established by a coating applied to the fastener and the conformable film.

   The sensor circuit includes an active conductor to induce the electrical response, and a passive conductor to sense the induced electrical response. The active and passive conductors are wound around an outer diameter of the mechanical coupler to form an alternating winding pattern of active and passive conductor lines. 

"When you plug this in, you can see if there is a crack and if it has propagated," says Bill Christopher, executive vice president of Alcoa.

Structural health monitoring (SHM) technology:

    Stanford University developed the structural health monitoring (SHM) technology under a research grant sponsored by Alcoa.

Alcoa's SHM system can be used for aluminum aircraft structures as well as hybrid structures that combine carbon fiber-reinforced composite and aluminum. For example, the SHM system can be applied to the joint between aluminum ribs and carbon fiber reinforced wing skins.

 

Pre-production prototypes of Alcoa's SHM system are currently being tested with select customers for commercial applications.  Alcoa plans to complete comprehensive testing with select customers before SHM reaches full production.

 
 

 

 

VORTEX SURFING SAVES FUEL AND MONEY

Flight tests with C-17s "vortex surfing" at Edwards Air Force Base, Calif., Sept. 6 and Oct. 2, have demonstrated potentially large savings of fuel and money by doing what geese do naturally. Tests show that flying in formation might be smarter than flying alone for Airmen, and not just for birds

Vortex surfing involves the whirlwinds of turbulence generated at the wingtips of planes in flight. Because they produce turbulence and drag, aeronautical engineers do their best to minimize these. That’s the reason for the little winglets on aircraft. Now, instead of trying to get rid of vortices, the USAF is trying to exploit them to increase fuel economy.

This may be cutting edge as far as aviation is concerned, but vortex surfing has been around a long time. In fact, nature has been exploiting it for millions of years. Geese flying in formation vortex surf. The lead bird generates vortices as it flies and the other geese position themselves inside the wave of turbulence also known as a slipstream. Though the lead bird is working hard, the vortices it generates increase lift for the following birds. The lead bird has to work harder, but the net energy savings for the flock as a whole goes down.

The concept, formally known as Surfing Aircraft Vortices for Energy, or SAVE, involves two or more aircraft flying together for a reduced drag effect like what you see with a flock of geese," said Dr. Donald Erbschloe, the Air Mobility Command chief scientist.

Early indications from the tests promise a reduction of fuel consumption by up to 10 percent for the duration of a flight. Over long distances and with even a small fraction of Air Mobility Command's average of more than 80,000 flights a year, the fuel and cost savings could reach into the millions of dollars, experts say.

The Air Force Research Laboratory will analyze the data from for possible applications to other aircraft on a variety of missions.

• Dr. Erbschloe said larger air mobility aircraft like the C-17 can fly in formations that are potentially easy to maintain and which do not require the planes to be exceptionally close together.

• "The test flights were flown at longitudinal separations of 4,000 or greater," said William Blake, one of the key developers of save at the AFRL.

• According to AFRL officials, modified C-17 formation flight system software enabled precise auto-pilot and auto-throttle systems to ensure the trailing aircraft achieved and maintained proper flight position without active assistance from pilots.

• "The autopilot held the position extremely well -- even close to the vortex," said Capt. Zachary Schaffer, an aircraft commander on one of the test flights. "The flight conditions were very safe; this was as hands-off as any current formation flying we do."

• Other pilots found differing levels of ride quality and discovered some flight test points might be difficult for long-endurance flights.

• "The key will be finding the right balance of quality for improving fuel efficiency and ride," said Maj. Eric Bippert, another aircraft commander on one of the test flights.

 

• Bippert said being a part of the test program with so many talented engineers was a remarkable experience, and the concept could eventually impact global air transportation, overall.

• "AMC has done really well with fuel efficiency at the operational level," said Erbschloe. "The command has worked to gain efficiencies from the 'low-hanging fruit' such as optimizing flight routing, reducing weight where possible, and by not carrying excess fuel. save offers significant efficiency gains, if employed in concert with these initiatives."

• He said early indications show the tests meet AMC criteria of the concept regarding safety and minimization of aircrew and aircraft strain while also being operationally sensible with a viable return on investment.

• "AMC consumes 20 percent of the fuel used by the overall federal government, so we're constantly looking for pragmatic ways to improve our fuel efficiency," said Erbschloe.

• "Assured energy advantage for our Air Force is only possible through revolutionary energy initiatives like save," said Dr. Mark Maybury, Air Force chief scientist, upon hearing the results of the tests.

• The save concept was previously highlighted in the 2011 Energy Horizons study, sponsored by the Secretary of the Air Force and chaired by Maybury.

• The tests were the culmination of an ongoing, combined effort between AMC, the AFRL, the 412th Test Wing, the Air Force Life Cycle Management Center, the Defense Advanced Research Projects Agency, the Boeing Company and NASA Dryden Flight Research Center.

Morphing leading edge reduces drag and noise in takeoff and landing

The morphing leading edge concept would replace traditional leading edge slats on fixed wing aircraft

      Passengers looking out the window of a passenger plane will likely have noticed slats on the leading edge of the wing, along with the flaps on the trailing edge of the wing, being extended during takeoff and landing. These leading edge slats provide the lift necessary at low speeds, with the gap between the wing and the slats directing air from the underside of the wing to the top. Unfortunately, this gap also generates a lot of noise. A team of researchers has now developed a morphing leading edge that eliminates the gap and reduces noise and drag during landing.

      The “smart droop nose” developed by researchers at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) working with partners Airbus, EADS Innovation Works and Cassidian Air Systems, literally morphs into a different shape during takeoff and landing so that no separate slats – and no gap – is necessary.

The morphing leading edge can be lowered by up to 20 degrees with virtually no loss of lift

      In developing the new leading edge, the researchers faced a number of challenges. "On the one hand, the structure needs to be very elastic, to enable it to morph to the required shapes, but on the other it has to be very rigid,” said DLR Department Head Hans-Peter Monner. Ultimately, the leading edge must bear around one third of the weight of the aircraft during landing."

The morphing leading edge is made from glass-fiber reinforced material

      The material also had to produce wing surfaces that are as flat as possible to achieve laminar airflow. Concentrating on the glass- and carbon-fiber reinforced composites typically used by the aviation industry, they found that glass-fiber reinforced material best fit the bill.

The droop nose design concept also sees the skin on the front edge of the wing curved, rather than stretched to minimize the stress placed on the material. Individual layers are then placed on top of each other so that the skin creates a structure with a customized rigidity distribution. The leading edge them morphs into the desired shape using actuators and support elements integrated along the wingspan.
The researchers have tested the system’s operation and performance in in one of Europe's largest wind tunnels at the Russian Central Aerohydrodynamics Institute’s (TsAGI) Zhukovsky research facility south of Moscow and found that the morphing leading edge can be lowered by up to 20 degrees with virtually no loss of lift.
The team plans to continue development of the concept to meet industrial requirements, such as lightning protection, de-icing and the ability to withstand bird strikes.

The morphing leading edge being tested at a wind tunnel in Moscow 

 

 

 This article is taken from AERO GIZMO.

Presentation on Aircraft propulsion system

This is my presentation on propulsion system of aircraft.
You can get basic idea of jet propulsion of aircraft in this presentation

To view the presentation click below

http://www.authorstream.com/Presentation/avionraky-1483268-aircraft-jet-propulsionsystem/

G-Suit

G.Force, you might familiar with this term. when you are in the giant wheel, little G-force can be experienced. But this is very small amount, we can not even sustain this small amount of G-force, then think about the Astronauts and fighter Pilots. they has to sustain the G-force of amount 3G to 10G.

                                Earth gravity is 9.8 m/s2. 
                                         3G = 3 * 9.8 m/s2
               now imagine      10G = 10* 9.8 m/s2
At this higher G-force our blood pressure goes to higher, and sometimes it leads to death.

There are two types of people experienced this G-force on a regular basis. Astronauts and fighter plane pilots.
Astronauts experiences when they are taking-off and re-entry situation. particularly when they re-entry.
when Astronauts re-entry to the earth atmosphere their space shuttle velocity is about 28,000 km/hr, this is hypersonic speed. at this situation they experience 10G.and their blood pressure is higher. To withstand this force they ware G-Suits.

How G-suit work : The suit is only pair of Chaps that has a waist that wraps around your gut. It has a hose that plugs into the aircraft which forces compressed air into bladders built into the suit. When the aircraft makes tight turns, causing g loads on the pilot, it forces the air into the lower legs, thighs, and gut area to force blood back up into the torso and to prevent it from pooling into your legs.

If they lose too much blood from their head under these loads they will lose consciousness and pass out. Once they pass out they will lose control and risk crashing. The G suit does not do all the work however, it only helps. The Astronaut in the spacecraft still has to do an enourmous amount of work to retain consciousness. They must flex the muscles in their legs and abs as hard as he can and take short, forced breaths.

After the re-entry Astronauts were loose their consciousness and feel giddy. It will take a week for them to come to normal situation.

SPACE ELEVATOR

Hello friends you might heard the story in MAHABARATHA, in which Arjuna was built a ladder to heaven through which Bheema was traveled.Yes its a story written by great "Vyasa maharshi". The same thing is going to be real now, you can travel to space and that too takes 5 hours journey, you can observe our Earth curvature and the sky turns to black color from blue. Which sounds like a Sci-fi movie story.

But this is not a story, this is real and this is really possible in our world, which is called SPACE ELEVATOR.

"Elevator to space". A space transportation system.Yuri Artsutanov first proposed the idea in 1960, and up until 15 years ago it was purely in the realm of science fiction. But Sumio Iijima's discovery of CARBON NANOTUBES (CNTs) in 1990 and Bradley Edward's engineering research in 2001 is clearing the road map to a space elevator's construction. Scientists today are conducting a lot of research in the field of nanotube tethers for commercial applications on Earth. Sooner than most people expect, I hope a space-elevator-capable CNT tether will become available and kick the space elevator's development into high gear.

 A space elevator is essentially a long cable extending from our planet's surface into space with its center of mass at geostationary Earth orbit (GEO), 35,786 km in altitude. Electromagnetic vehicles traveling along the cable could serve as a mass transportation system for moving people, payloads, and power between Earth and space. Current plans call for a base tower approximately 50 km tall -- the cable would be tethered to the top. To keep the cable structure from tumbling to Earth, it would be attached to a large counterbalance mass beyond geostationary orbit, perhaps an asteroid moved into place for that purpose.

Carbon nanotube :
         

                CNT is a new form of carbon, equivalent to a flat graphene sheet rolled into a tube. CNT exhibits extraordinary
mechanical properties: the Young's modulus  is over 1 TeraPascal and the estimated tensile strength is 200 GigaPascals. Fiber materials such as graphite, alumina, and quartz have exhibited tensile strengths greater than 20 GPa during laboratory testing for cable tethers. The desired strength for the space elevator is about 62 GPa. Carbon nanotubes have exceeded all other materials and appear to have a theoretical strength far above the desired range for space elevator structures. "The development of carbon nanotubes shows real promise," said Smitherman. "They're lightweight materials that are 100 times stronger than steel."

And there are some more technologies to build such a elevator.but CNT is the present assumption.

In his last years, Sir Arthur C. Clarke predicted that the space elevator will be built "about 10 years after everyone stops laughing". I believe people will stop laughing once a proper tether is demonstrated, and we think that this will happen within 5 to 10 years. Hopefully that means about 15 to 20 years before the first launch.

 Conceptual pictures:

Videos:

 NOVA Science now video

Hummel Helicopter

Exited....? Even i was exited.

This is the new concept of light weighted helicopter with TANDEM DUCTED ROTOR design.

The passenger capacity is two and it will not take more space, it can be folded flat.

The Hummel could be of great help in emergency situations, when there is minimal space, because of its small size and folding ability.

Hemmel means "Bumble bee"

But this is just a conceptual design.It won't take much time for prototype.

It can be used for passenger transport, emergency transports like organs or units of stored blood and for conventional tasks, such as monitoring (e.g. coast guard, police, army, scientists).

This dose not require Helipad.

Further detail click the link below: