The first Indian planetary mission to moon, Chandrayaan-1, launched on 22nd October, 2008, with a suite of Indian and International payloads on board, collected very significant data over its mission duration of close to one year. This mission was a huge success. Here we present some of the achievements of Chandrayaan -1.
TYPES OF PROPULSION SYSTEM
Missile propulsion will be mainly of the following two types:
The air breathing rocket engines use the surrounding medium of' air for the support of their oxidiser. Thus they can be used only within the Earth's atmosphere whereas in the case of non-air breathing engines the rocket engine itself' carries its fuel and oxidiser on board and hence can be used in space above the Earth’s atmosphere also and is thus independent of the air medium.
Depending on the physical state of matter of the propellant used, the rocket propulsion system is designated as a solid rocket motor, a liquid propulsion system or a hybrid propulsion system.
The Predator UAV is a medium-altitude; long-range aircraft that operates much like any other small plane. These high-tech aircraft, controlled by a crew miles away from the dangers of combat, are capable of reconnaissance, combat and support roles in the hairiest of battles. In a worst-case scenario, if a Predator is lost in battle, military personal can simply "crack another one out of the box" and have it up in the air shortly -- and that's without the trauma of casualties or prisoners normally associated with an aircraft going down.
PRIMARY FLIGHT CONTROLS
Aircraft primarily controls itself by using its primary flight controls. These are
Propulsion is the means of providing power to accelerate the missile body and sustain, if necessary, to reach the required target. The basis for the working of missile propulsion systems are the well-known Newton's laws of motion. In order to aid a quick retrospect, these are stated here again.
A body continues in its state of rest or in uniform motion in a straight line unless acted upon by an unbalanced force.
When two solid objects interact in a mechanical process, forces are transmitted, or applied, at the point of contact. But when a solid object interacts with a fluid, things are more difficult to describe because the fluid can change its shape. For a solid body immersed in a fluid, the "point of contact" is every point on the surface of the body. The fluid can flow around the body and maintain physical contact at all points. The transmission, or application, of mechanical forces between a solid body and a fluid occurs at every point on the surface of the body. And the transmission occurs through the fluid pressure.
Definitions of Lift and Drag
Since the fluid is in motion, we can define a flow direction along the motion. The component of the net force perpendicular (or normal) to the flow direction is called the lift; the component of the net force along the flow direction is called the drag. These are definitions. In reality, there is a single, net, integrated force caused by the pressure variations along a body. This aerodynamic force acts through the average location of the pressure variation which is called the center of pressure
What is a missile?
Basically any object thrown at a target with the aim of hitting it is a missile. Thus, a stone thrown at a bird is a missile. The bird, by using its power of reasoning may evade the missile (the stone) by moving either to the Left, right, top or bottom with respect to the flight path (trajectory) of the missile. Thus, the missile in this case has been ineffective in its objective of hitting the bird (the target). Now, if the stone too is imparted with some intelligence and quick response to move with respect to the bird, to overcome aiming errors and the bird's evasive actions and hit it accurately, the stone now becomes a guided missile.
The incorporation of energy source in a missile to provide the required force for its movement (propulsion), intelligence to go in the correct direction (guidance) and effective maneuvering (control) are mainly the technologies of guided missiles. They help in making a missile specific to a target, that is, they determine the size, range and state of motion of a missile.
Types Of Guided Missiles
Presently, there are many types of guided missiles. They can be broadly classified on the basis of their features such as type of target; range; mode of launching; system adopted for control, propulsion or guidance; aerodynamics; etc. They are also termed in a broad sense as strategic or tactical, defensive or offensive.
On the basis of target they could be called
Year 2100, ISRO, s robotic probe is conducting experiments in keiuper belt outside the solar system. Suddenly the probe detects some unusual signals. Scientists at ISRO confused, they have no idea where did these signals came from. The disturbance in communication between ground station and robotic probe is increasing. All the radar stations are pointed in the direction of the robotic probe. Within matter of minutes Scientists found huge electromagnetic wave patterns. ISRO concluded probably some kind of communication system, but who are they? The whole world turned towards that what they found was shocking news. A fleet of alien crafts rapidly approaching earth, is this is the end of Homo sapiens?
The above described scenario is not unlikely. In this vast universe there is all the possibility of an advanced civilization. What we do if that alien civilization attack us. In the present technological advancement is not enough to counter an alien threat. But in the future surely we develop something to counter an alien invasion. Here is a brief idea about countering an alien attack.
Every enemy has a weakness we should find out what it is. To repeal an alien attack we need three things.
1)Intelligence: we need to know who they are , what their strength and weakness
2)Defense : we need to reinforce the lines of defense to protect earth
3)Attack strategy : if they do land on earth we need weapons & strategy to counter them
We need an early warning system to detect the aliens. Radars are the best choice for that. We need to monitor the entire solar system; the intruders will come in any direction. But there is a problem the area of solar system is 6*10 26 sq miles. We can’t monitor this much area using the radar systems on the earth. But there is a solution. The outer edge of the solar system is the aur cloud a region of huge comets. We can use those comets as radar stations & can create a network of radar system that can monitor the entire solar system and can monitor the intruders in every direction.
Still there is some problems these alien crafts may be stealthy even humans are using stealth aircrafts , ships etc. maybe we can find the larger mother ships but it is not easy to find the tiny alien probes dispatched from the mother ships especially most of the outer space radars using high frequency electromagnetic waves. Hmm we need something else to find the alien ships. To detect the stealth alien ships we can use another frequency called X-rays. X rays are very small i.e.; they are billions of times smaller than the radar signals they can pick up an object in the size of sand X rays are ideal solution for finding alien intruders and also we can create ultra sensitive X ray scanners on board robots and place them in aur clouds & can fly through the comets and scan for tiny alien probes.
The following are some of the real pictures of scramjet, tested by the ISRO some months ago mounted on a Rohini Rocket. This is a brief description of scramjet based on these pictures. We are preparing a detailed article about different propulsive devices including scramjet, so followers will get more information about scramjet in the coming days.
What is a scramjet?
Scramjet, or Supersonic Combustion Ramjet is a kind of air breathing (It sucks the air from atmosphere) propulsion. In scramjet the combustion taking place at supersonic speeds while in other air breathing propulsive devices, combustion occurs at subsonic speeds. Scramjets are simple devices compared to jet engines which also are air breathing propulsion. Unlike jet engines scramjets doesn’t have any moving parts to compress the incoming air that makes scramjets less complex than the jet engines.
Scramjet typically works well in hypersonic speeds and is not suitable for supersonic and subsonic speeds. For supersonic speeds ramjets are the best option. In ramjets the intake decelerates the incoming air to subsonic speeds and then ignites the subsonic compressed air to supersonic speeds. But in scramjets the combustion take place at supersonic speeds so does the exhaust gases accelerate to hypersonic speeds.