An aeroplane flies about 400-500 metres above the water at a speed of approximately 60 - 70 m/s. Then the aircraft will send out a pulse which is moderately reflected off the surface of the water and moderately broadcasted into the water and reflected off the oceans floor, as a result two pulses are sent back to the aircraft. The pulse which was reflected of the surface of the water is a red beam (infrared) which measures the aircraft height above the water and is directed vertically downward. The beam which reflects off the seabed is a green colour and is examined over a semicircle of +/ -15 degrees to the planes bearing and pulsates at approx 160 pulses per second.
The aircrafts equipment will record the speed of the wave and the travel time during air to calculate depth . Therefore LADS must be flown during hours of darkness to eliminate the errors caused by the reflection of the sun off the water, which return false reading to the aircraft causing inaccurate depth.
The calculate the green beam (which travels to the seabed and back up) you must obtain the speed of light in water which is given by Maxwell?s equations which basically show that When passing through a transparent or translucent material medium, like glass or air, light will have a slower speed than in a vacuum . Therefore the extra time and distance traveled by the green pulse can be calculated, giving the depth of the water.
The aircraft needs to use two beams to ensure that the pulses return to the aircraft. In certain situations the pulse may not return to the aircraft due to flat glassy water surface (because of the law of reflection) . The Lads software automatically compiles arrival times and fixes errors in the data like tidal variations. Maps can be made after data is compiled from the aircraft by using Global Positioning Satellites, which constructs coordinates and data collected.
The green laser is used due to its incorporation of light in murky waters is the slightest at these wavelengths. One laser is applies which creates an infrared laser. A frequency double then changes the frequency of a fraction of the beam by a aspect of two , resulting in a green light laser.
Some Advantages and Disadvantages of LADS include:
Advantages Disadvantages
? A quick and effortless way of measuring depth of waters.
? Can compile its data and send it to satellites, which create map images.
In our lifetime, the ocean has remained untamed and unexplored. “Modern Day” technology has only been able to come so far in venturing out to sea and to the world below the surface. However, in the past 10 years this has all been changed. With research being done throughout the world studying the movement and anatomy of fish, the gap between the surface and the sea floor could be speedily lessening. For years humans have marveled at the speed and grace of most marine life. The lack of drag, the force propulsion, and the ability to live at such impossible depths have been forever the envy of submarines and sea explorers. After years of observing these incredible functions, researchers are finally beginning to mimic and apply these characteristics to marine technology. These robo-fish hold the potential to make underwater exploration far more accessible, safer, and more efficient due to their naturalistic design.
In seismology, there are several types of waves studied, each of these waves have characteristics that define them. Seismic waves can be split into two categories, and they are body waves and surface waves. Body waves travel and move within the earths subsurface and inner layers. There are two types of body waves, P-Waves also known as compressional waves or primary waves, and S-Waves also called secondary or shear waves. The S-Waves have a vertical (Sv) and horizontal (Sh) component. “In an infinite homogenous isotropic medium, only P and S waves exist” (Telford et. al, 1990). On the other hand, as indicated by the name, surface waves travel and move along the surface of the earth. In general, surface waves have a lower frequency than body waves, therefore, they can easily be distinguished from body waves on a seismogram. There are two types of surface waves, Love waves and Rayleigh Waves. Love waves is the fastest surface wave, its movement mainly consists of a side to side completely horizontal motion. Rayleigh (1885) waves are surface waves that “roll” along the ground; they are a consequence of interfering P and Sv-Waves. Our project
In this treatment, two types of laser beams are utilized. First is an erbium YAG laser and the other is a carbon dioxide laser. YAG laser was used earlier which is now replaced by the modern type carbon dioxide laser.
Hackmann, Willem Dirk. “SONAR.” Encyclopedia of World War II. Vol. 2. New York: Facts on File, 2007. Modern World History Online. Web. 21 Mar. 2012. .
Aviation has come a long way since the 19th century, from the Wright brothers taking flight with the first powered and controlled gliders, to aircraft that can travel up to supersonic speeds, orbiting satellites and space stations which then were only thought to be science-fiction. Aerospace and aviation has proven to be one of the biggest challenges to advance in the entirety of human existence. There are many factors and characteristics that contributed to this advancement such as the engines of aircraft, forces of flight, aerodynamic forces, wingspans etc. The two most significant aspects however have been; World War 1 and World War 2.
Ultrasounds use the same concepts that allow sonar on boats to see the bottom of the o...
El Niño is detected using satellites, moored and drifted buoys, and a sea level analysis.
These theories attract the most attention, and are what have promoted the Bermuda triangle to the status of “Legend”. Now, let us explore some of the more prominent ones, namely the Electronic Fog theory, the Hutchinson effect, and government experiments with advanced radar at AUTEC naval base. Electronic Fog will be the first theory discussed in this paper. Electronic fog is a theory first publicized by Bruce Gernon, and several others have claimed to witness the fog, as they call it. Generally, it is described as a gray fog which causes instruments to go crazy, pilots and passengers become dizzy or unconscious, and in some cases, time warps.
Review: The opportunity and endeavor of exploring the Earth’s oceans can reap great rewards for mankind and unravel many of the mysteries that the Earth has left to discover.
“How and why is it that I do not describe my method for remaining underwater and how long I can remain there without coming up for air? I do not wish to divulge or publish this because of the evil nature of men, who might use it for murder on the sea-bed.” – Leonardo Da Vinci [1].
the history of our mission to conquer the underwater world.” Geographical Aug. 2005:54+. Student Edition. 3 Nov. 2009 .
There are two causes of ocean currents: wind and convection. The more important of the two is convection. The act of convection in a fluid is the tendency of a heated part of the fluid to rise up due to the fact the it is less dense and it is replaced by cooler fluid which is then heated, rises up, and again replaced by cooler fluid. There has been plenty of recent research on the topic of ocean currents and convection, some of which might change the way we view the ocean. In this paper I will explain exactly what convection is, I will explain how and why it makes such a drastic effect in our ocean, and I will discuss the latest research that has been done on ocean currents.
Tillery, B. (2012). Wave Motions and Sound. Physical science (9th ed., pp. 115-134). New York,
Sound waves are measured in frequency which can be defined as the number of pressure waves passing a fixed point in a set time. “The velocity of sound in seawater is approximately 1500ms”(Wright et al., 1995, p. 71) Wavelength is the distance
The Global Positioning System consists of three sections, 1.satellites which are orbiting the planet, 2.there are numerous control/monitoring centers here on the ground, and 3. gps receivers which are used by their owners. The satellites send down signals from orbit, which are received by GPS receivers on the ground in the air or on the water, the GPS receiver then converts this information into a location longitude, latitude and altitude along with time.