Americans develop a plane that does not need to go down to the ground

Americans develop a plane that does not need to go down to the ground
A team of South American Institute of Lehigh is preparing a large unmanned aerial vehicle that is designed for continuous operations. Back in 1883 the Nobel Prize winner John Strutt, Baron Rayleigh physicist also nominated one constructive idea. John Strutt explored the mechanics of bird flight, namely, pelicans, and put forward the assumption that birds drew power for the flight from the difference of wind speeds, which in turn allowed them to soar in the sky without flapping their wings. Applying this technique of flight, which was designated as dynamic soaring, the aircraft could have, at least on a theoretical level, to fly without actually using the fuel for many weeks, months and maybe even years.

Dynamic guy by the name itself hover mode, in which the altitude is maintained by constantly changing layers of air, owning good horizontal velocities. Areas of significant gradient wind speed in most cases occur in any interference or the air flow near the surface. This method is quite often used birds. In most cases, it is used by sea birds that hover over the ocean waves, cycling strongly little energy for flight. In particular opytneyshemi in applying this method numbers of albatrosses that using dynamic soaring can travel many thousands of miles. Glider pilots in turn occasionally find quite similar gradients on huge heights.

Dynamic soaring based on the fact that the wind speed at each next layer is higher than in the past. For example, the strong wind speed at a height of 1 meter is 10 m / s, but if you climb to a height of 10 meters, the wind speed at her Strength 1.5. This phenomenon, which is particularly noticeable on the surface of aqua, very intensively use large birds: sea and ocean birds. Initially, they are rising to the upper air, to stock the desired inertia, then make a loop, vorachivayas into the lower layers of air at high speed. At the time of the cycle repeats birds or any of their synthetic analogs accelerated even stronger.

In the over 10’s years of work on dynamic soaring moved very slowly. Operators of radio controlled gliders used the advantages of this technology in order to increment the flight range, but scientists did not know whether you can apply this knowledge to larger aircraft. Despite this, in 2006 a team of engineers, which consisted of members of NASA and the U.S. Air Force took a long flight on a modified glider L-23 Blanik over air base Edwards, in practice, proving that a fairly large aircraft able to use the technique of dynamic soaring.

It should be noted that modern gliders quite often and have long use bird techniques to accelerate and climb. For example, in 2005, the Centre NASA flight research them. Dryden launched glider with the autopilot, which has managed to survive in the sky for an hour longer everyday due to the fact that catching thermals (so-called static hover). And in 2009, comparable to a small radio-controlled airplane was able to accelerate to 630 km / h, by using the method of dynamic soaring.

Currently, a team from the Institute of Lehigh, led by Dr. Joachim Grenshtedt engineering, is working on improving the concept of dynamic soaring. They try to make a big drone, which is designed to perform continuous operations. Not so long ago, they finished work on the creation of a 7-meter wing made of carbon fiber and designed for operation in the jet streams of air at a height of more than 6 km. This model should overload to 20 G (dynamic soaring causes severe wing loading machines) speeds up to 480 km / h

Later in 2013, this team of researchers is going to run tests with the model glider technology on a small height. In this case, these tests will be successful, says Grenshtedt, they are going to launch its own aircraft, received the title «Jet Streamer», in the jet stream, in which the wind speed can reach 320 km / h How to get rid of aircraft engineer cargo of fuel and power plant, flying in the sky can be reincarnated into something entirely new.

In the distant future, dynamic soaring aircraft fail to become observational platforms that will be able to monitor feral animals, people or the weather. Also they will be able to serve the communication transmitters, cellular or relaying television signals. In addition, they will even get the opportunity to travel at very high speeds over long distances.

How it works: Dynamic soaring based on the difference in wind speed

1. Glider rises, overcoming layers of measured air at low altitude to a more rapid and the highest layers of the air nose to the wind.
2. Glider retains its ground speed as it passes through the boundary air flow. Headwind assigns a higher airspeed and generates more lift as it moves across the wind of its wings.
3. Make a turn, the glider soars down, breaking with all this considerable distances.
4. Leaving windy layers of air, the glider climbs back to repeat the maneuver own. Until that time, as there is a difference in wind speeds, the cycle will be doing an infinite number of times.


Created by Sergey Yuferev
SQL - 16 | 0,464 сек. | 6.93 МБ