Underwater Missiles - TORPEDO

Generally, most of the people assume that torpedo can only launched from a submarine or a U-boat. But not all torpedoes can be launched from a submarine. This is because a light torpedo can be dropped by an aircraft for a close attack, while the heavy torpedo, a standoff weapon are launched by submerged submarines.

Torpedo is a self-propelled mechanism, explosive projectile weapon. It can be launched above or below the water surface. These torpedoes will propelled underwater towards a target, and is designed to detonated either on contact with the target or in proximity with the target.

Back about in 1900, "torpedo" has been used strictly to designate an underwater self-propelled missile. The first working prototype of the modern self-propelled torpedo was created by a commission placed by Giovanni Luppis with a blue print of it, and Robert Whitehead perfects it to be a self-propelled torpedo in 1866.

Modern torpedoes are the Homing Torpedo type. These torpedoes can be used as passive or active guidance, or a combination of both. The passive acoustic torpedoes home in on emission from a target, while the Active acoustic torpedoes home in on reflection of a signal, or "ping", from the torpedo or its parent vehicle. The disadvantage about the signal is that it gives away the presence of the torpedo.

During semi-active mode, a torpedo can be fired to the last known position or calculated position of the target, which is then acoustically illuminated ("pinged") once the torpedo is within attack range.

In the Second World War, the German torpedoes, G7 es torpedoes; were designed to have acoustic (homing) guidance systems. Pattern-following and wake homing torpedoes were also developed during that era. After the Second World War, the basis for torpedo guidance for acoustic homing torpedo was formed.

Torpedo Hits A Destroyer

# Teet teet # - Incoming Missile Detected -

Strategic and Tactical missile detection require basically two functions. One of these functions is that the detection of the missile being launch and the burning fuel from the propellant during the acceleration into ballistic trajectory. The other will be the tracking of the missile on where it is targeted.

Normally, strategic and tactical missile launch detection and tracking systems use infrared surveillance techniques that employed by satellite sensors.

Satellite sensors are required to view the entire whole earth at one time, because the missiles could be launched from any location at any time. Furthermore, it is a must for the satellites sensors to detect where the missile probably going and, from the trajectory, to find where the missile would preferably hit with a high proba

bility detection.

Many known missile detection systems sense

infrared radiation in a single band. This band contains information about the missile as well as unwanted background. On the other hand, the composite signal contains actual, but weak, target signals which are less than the threshold over a portion of the detection band. It is to say that, when the threshold level is raised too high, many actual targets would remain undetected, that would cause a false alarm due to false detection.

Military Spy Satellite

First of all, Spy Satellites is referred as military reconnaissance and surveillance satellites. Though these Spy Satellites operate in many parts of the electromagnetic spectrum, these military satellites provide intelligence of the enemy capabilities and their activities.

The first generation of spy satellites was Corona and Zenit. During the development of these satellites, it was officially requested and demanded by the United States Air Force dated March the 16^th, 1955.

The main purpose of the demands was to have a continuous surveillance of some areas of some potential enemies in determining the weapons-making capabilities. Between the year of 1957 and 1999, about 4000 satellites were launched into space without fail, and about 50 percent of these satellites, will be used for specifically military purposes. Other functions of the satellites are such positioning and navigation, analyzing and recording information about the terrain (remote sensing), geodesy, research and meteorology. Though other satellites such as civil commercial satellites were used at times for several military tasks, which includes command assistance and military logistics support; a satellite with purely military uses, have certain capabilities and multiple systems that is specify for military uses that differs from the commercial ones.

NAVSTAR GPS (Navigation Signal Timing and Ranging Global Positioning System), is one of the best example of a military satellite that is operated by the US Air Force. It was first launched in 1978, but for the system to be fully operational was declared in April, 1995. The NAVSTAR satellites are arranged in six planes, each orbit back to the same spot on earth in a 12 hour, 20,000km high orbit. Each of the satellite will broadcast out two L-band radio signals containing ranging codes, ephemeris parameters, and Coordinate Universal Time (UTC) synchronization information. Other military users such as civilian users are able to receive, decode, and process the signals that receive from the NAVSTAR-GPS, to gain 2D or 3D position, velocity and time information. Civilian receivers then to lack of ability to read coded portions of the satellite transmissions.

References:

David Darling - The Internet Encyclopedia of Science: Satellites & Space Probes, “NAVSTAR (Navigation Satellite Time and Ranging)” [Online] Available from http://www.daviddarling.info/encyclopedia/N/NAVSTAR.html [Accessed on 17th January 2011]

Charlie Leonard (1999) – Introduction to NAVSTAR GPS. [Online] Available from http://people.csail.mit.edu/rudolph/Teaching/Lectures07/L8-navstar-2.pdf [Accessed on 17th January 2011]

Nicholas M. Short – RST, Introduction Technical and Historical Perspectives or Remote Sensing “Military Intelligence Satellites”. [Online] Available from http://rst.gsfc.nasa.gov/Intro/Part2_26e.html [Accessed on 17th January 2011]

Jason C. Chacis (2010) – BrightHub, Space Technology “Military Satellites: Meaning and Purpose”. [Online] Available from http://www.brighthub.com/science/space/articles/26768.aspx [Accessed on 17th January 2011]