Basic Weaponry and related

Indian Sniper.001

Senior Member
Joined
Sep 22, 2016
Messages
1,454
Likes
6,737
Country flag
To be honest, many are blank when it comes to weaponry, or atleast I am. I don't have the grasp of weaponry, like I have on strategy (well, not an expert by any means, just better than the grasp I have on weaponry). Obviously, can't ask doubts on a particular thread and derail it, thus opening a new thread. Let anyone who has basic questions are noob in this subject ask questions without having the thought that it is stupid, after all everyone here is here to learn, and we can learn from each other. Hoping, this thread gets a good response. Yes, could have searched on google, but I felt this thread was missing on the forum for guys like me to raise noob and stupid questions and be a one stop place for seeing all basic weapons related questions, rather than search multiple times, hope you don't mind. My first question will be in the next post.
Tagging a few of them whom I think can contribute after seeing their answers on various questions, please feel free to untag yourself if not interested, and my sincere apologies for tagging if uninterested.

@Kunal Biswas @Mikesingh @lcafanboy @LETHALFORCE @pmaitra
 

Indian Sniper.001

Senior Member
Joined
Sep 22, 2016
Messages
1,454
Likes
6,737
Country flag
What is stealth and how does it need to be designed to get the status of being a stealth jet?
 

Shashank Sharma

Regular Member
Joined
Oct 23, 2016
Messages
47
Likes
36
What are the basic components in a rifle? I hear various confusing terms such as bolt, receiver, firing pin and I am unable to understand anything.
 

Johny_Baba

अज्ञानी
Senior Member
Joined
May 21, 2016
Messages
3,794
Likes
19,388
Country flag
What are the basic components in a rifle? I hear various confusing terms such as bolt, receiver, firing pin and I am unable to understand anything.
I wish i could answer all of your doubts but unfortunately nowadays i don't have that much free time.Still,I will give you some hints.

I would recommend you to underatand how bullet fires,and to understand it first learn about internals of bullet.

Next step would be to understand how Kalashnikov rifle (AK-47) fires.Believe me,by just looking at its operation many doubt related to basic firearm terminology will be solved.

There are plenty of Youtube channels where you can learn about these things.

At last,I would recommend you to install a game called 'World of Guns:Guns Disassembly' on Steam in case you have a pc with good internet connection.
Buy 'Weapons full access' pack which would allow you to access all firearms and it may help you give some basic information about operation of various firearms in interactive manner.
 

Shashank Sharma

Regular Member
Joined
Oct 23, 2016
Messages
47
Likes
36
I wish i could answer all of your doubts but unfortunately nowadays i don't have that much free time.Still,I will give you some hints.

I would recommend you to underatand how bullet fires,and to understand it first learn about internals of bullet.

Next step would be to understand how Kalashnikov rifle (AK-47) fires.Believe me,by just looking at its operation many doubt related to basic firearm terminology will be solved.

There are plenty of Youtube channels where you can learn about these things.

At last,I would recommend you to install a game called 'World of Guns:Guns Disassembly' on Steam in case you have a pc with good internet connection.
Buy 'Weapons full access' pack which would allow you to access all firearms and it may help you give some basic information about operation of various firearms in interactive manner.

Much appreciated! Thank you! +++++
 

nongaddarliberal

Senior Member
Joined
Nov 1, 2016
Messages
3,939
Likes
22,313
Country flag
What is stealth and how does it need to be designed to get the status of being a stealth jet?
A stealth aircraft must be shaped in a way, and coated with a material that makes incoming radar waves bounce off in another direction, or get absorbed in the coating itself, so that the radar that sent the waves doesn't receive them back, which means it cannot detect the plane. The technical term is RCS, Radar Cross Section. The goal is to achieve the minimum RCS possible in a plane.

Regarding shape, common strategies include having angled sides on the plane which will deflect the radar waves in different directions. Another aspect is to remove all irregularities on the surface. Any irregularity on the surface will add to the RCS of the plane, which is why weapons in 5th gen fighters are stored in internal bays, so that the missiles don't change the smooth exterior shape of the plane. In a proper 5th gen aircraft, even the engine outlet has stealth features, such as the f 22 or Yf 23 Black Widow (Sexy beast).

The second component is radar absorbent coating. I'm not sure what exactly the material being used is. Maybe someone can shed some light on it. But the point is it absorbs radar waves.

It must be noted, that even aircraft that are not officially called stealth aircraft can have much lower RCS than other planes of the same generation. An example is the rafale which has a lower RCS than a Su 30MKI. Another example is the F 15 "Silent Eagle" sold to South Korea, which is an F 15 with additional stealth features.
 

Indian Sniper.001

Senior Member
Joined
Sep 22, 2016
Messages
1,454
Likes
6,737
Country flag
Cross posting from Agni-Vi thread.

Regarding range, once the missile is outside the earth's atmosphere it can coast forever. In a sense it will in in orbit around earth and therefore have an almost unlimited range.

For example, where the Agni 5 is concerned, the first stage is fired for 90 seconds, getting the missile to 40 kms altitude, the second stage separates at the 155 second stage, getting the A-5 to 110 kms altitude, and the third stage separated after firing for the next approx 135 seconds to reach the missile into space and outside of the earth’s pull, with the built-up momentum taking the A-5 to its ballistic apogee of around 600 kms.

At this altitude, a missile is in orbit around the earth. For example, the CARTOSAT series of satellites have an orbit with a perigee of 200 km and an apogee of 1,200 km above the earth’s surface and will be in orbit for the better part of a decade covering millions of kms.

Thus the A-5 with an apogee of 600 km can be in orbit almost indefinitely, resulting in an infinite range like other ICBMs. But it needs to be got down to hit the target for which an enormous amount fuel is needed for re-entry into the atmosphere. Here lies the rub! Fuel! :cool3:

By the way, early Soviet and American manned orbital missions used modified ICBMs as launch vehicles.
@Mikesingh sir, please can you explain a bit more on the basics of ICBM missiles and how they work - I mean the stages and stuff. Thank you.
 

Mikesingh

Professional
Joined
Sep 7, 2015
Messages
7,353
Likes
30,450
Country flag
@Mikesingh sir, please can you explain a bit more on the basics of ICBM missiles and how they work - I mean the stages and stuff. Thank you.
Bro, I suggest you check out this infographic which would explain the fundamentals...



A launch vehicle capable of putting into orbit a world-circling satellite can also be used to send a nuclear warhead to any point on the surface of the Earth. But remember, peak speed for an ICBM is in the ballpark of 6-7km/s (any faster and the payload would go orbital), and it takes about 10 minutes to accelerate to that speed.



A ballistic rocket, also known as intercontinental ballistic missile, burns up all its fuel in order to put the warhead on a ballistic trajectory, and then the warhead goes back through the atmosphere very much like a deorbiting spacecraft. Essentially, there is no reason why you couldn’t put the warhead into orbit, keep it there for a while and then deorbit when convenient. This, however, is not deemed practical as it is assumed that the missile launch will trigger a retaliatory strike, so making circles around the Earth is a waste of precious time.

Phases

The first phase is the Active Phase which includes Boost Phase, because in this phase the trajectory can be fixed by the thrust, which can also corrects the trajectory in following passive phase.

The second phase is the Passive Phase which include both Midcourse Phase and Terminal Phase, because in this phase, there is no more thrust supplied to change the trajectory actively.

For the first phase, the ballistic missile is supplied thrust by the propulsion system. At this occasion, all thrust, gravity force and air resistance affect the trajectory.

For the second phase, only gravity force and air resistance affect the trajectory.

So the Active Phase is the most important part. In this phase, the missile not only rises upwards but also finishes the initial part of the correct trajectory(curve), so that 3-5 minutes later, when the fuel burns out, the ballistic missile will move in the rest of the trajectory only in the effect of gravity force and air resistance and hit the target accurately.

However, remember if the speed is > 7km/sec the missile would go into orbit around the earth and you would need extra fuel and thrusters to decelerate it to bring it back to earth. With a missile having MIRVs the situation gets even more complicated!

Cheers!
 

bhramos

Senior Member
Joined
Mar 21, 2009
Messages
25,625
Likes
37,233
Country flag
silly question for newbies

What happens when bullet fire in air? does it kill anyone who is under it?
 

Krusty

Senior Member
Joined
Nov 26, 2015
Messages
2,529
Likes
4,869
Country flag
silly question for newbies

What happens when bullet fire in air? does it kill anyone who is under it?
I have no prior knowledge so am answering purely from a scientific perspective. Too many variables. Type of gun/rifle. Type of round used. Angle at which it's fired. Fitness of the individual and where the bullet lands.

For simplicity sake I'll take a 9mm handgun fired straight up as an example, the falling bullet will reach a terminal velocity (thanks to air resistance) which is far lower than what it had exiting the barrel. I Guess a healthy individual can survive a 9mm bullet falling in his shoulder or even his head. It probably will leave a painful sore. Landing on eye or ear will probably kill. (Larger rounds like. .50 cal might still have enough momentum to shatter the skull perhaps, but it's a Guess)

Shooting at increasingly lesser angle increases the lethality since the effect of gravity slowing down the bullet becomes lesser, the flatter the angle gets.

As a rule, the farther away from the gun you are (fired upwards at angles) the lesser the chances of surviving the hit. All other variables being constant. The bigger the round the farther (and the higher the angle) the lethal reach.

Noob answer I know. But my best Guess.
 

Dovah

Untermensch
Senior Member
Joined
May 23, 2011
Messages
5,614
Likes
6,793
Country flag
silly question for newbies

What happens when bullet fire in air? does it kill anyone who is under it?
There are a few reported injuries/fatalities from falling stray bullets every year. But the probability of a stray bullet to hit a person is very low.
 

bhramos

Senior Member
Joined
Mar 21, 2009
Messages
25,625
Likes
37,233
Country flag
There are a few reported injuries/fatalities from falling stray bullets every year. But the probability of a stray bullet to hit a person is very low.
your answer is quite near my expectation, every year 100s get injured during pakistani kite festival, during that time 100's of people fire into air

 

Gessler

Senior Member
Joined
Jan 10, 2016
Messages
2,296
Likes
11,129
Country flag
What is stealth and how does it need to be designed to get the status of being a stealth jet?
I'm gonna try to keep the whole thing as brief as possible...

The term 'stealth aircraft' is used to denote a plane that's designed to be very difficult to detect or track with radar. Otherwise known as Very Low Observable (VLO) planes. Examples are the F-117, B-2, F-22, F-35, PAK-FA, J-20 and J-31.

Note that stealth aircraft are not completely invisible - they just reduce the DISTANCE at which they can be detected by radar. For example, if a non-stealth aircraft like Su-30MKI can be detected by an X-band radar at a distance of 100km, then that same radar would be able to see an F-35 at around 10-20 km only. (Numbers are only for example).

How to make an aircraft stealthy? To understand this one first needs to understand how a radar works: a radar has a transmitter & a receiver. The transmitter sends out a waveform of radiowave energy which bounces off any surface they touch and scatter in different directions (depending on the nature of the surface) and some of the bounced waves return back to the receiver on the radar. By measuring the time between transmission & reception, and the direction they came from, a radar can register that there is an object at X distance from itself, at a set bearing. Radars of higher resolutions (such as those carried by jet fighters) can accurately scan the size & shape of the object they are looking at, helping the radar computer to identify the object.

Note that every object has a quantifiable amount of surface area which is capable of reflecting a wave back to the radar - this is called that object's Radar Cross-Section (RCS) and is usually measured in square meters.



So how can an aircraft prevent getting seen by a radar in this way? The PRIMARY method for aircraft stealth today is AIRFRAME-SHAPING. The surfaces of the aircraft have to be designed in such a way that they reflect as less radar energy as possible. Note that a radar will see the aircraft only when a radiowave coming from the radar touches the aircraft and GOES BACK TO THE RADAR. The surfaces on a stealth aircraft are designed to deflect the radiowave away from the direction it came from. If enough radiowave energy fails to travel back to the receiver, the radar registers nothing (note that a little bit of energy still goes back, but it's too little to matter. We'll get to that later).



If you look at the surfaces on stealth aircraft, you'll see that they have very specific angles designed to ensure that their surfaces manage to face a radar from an angled position as much as possible, avoiding perpendicular contact wherever possible, reducing it's RCS.



This attention to aspect angles removes a majority of the radar return which a plane would otherwise have if it were conventionally designed (with only aerodynamics in mind). But this is not enough to make a stealth aircraft. A stealth jet also needs to have internal weapon bays (as missiles & bombs are not designed to deflect radar and are therefore easy to detect) in order to remain combat-effective while still maintaining stealth.

However, a good stealth shape isn't always a good aerodynamic shape. So when designing an aircraft that's supposed to have great aerodynamic performance (like a fighter), it's imperative to make a few compromises with regard to stealth-shaping. Like sharp edges/corners etc. This is where the many SECONDARY stealth methods come into play, such as:

  • Radar-Absorbent Materials (RAM). This malleable, paint-like material is applied on the parts of an aircraft where stealth-shaping is impossible as doing so would destroy it's aerodynamic properties. Such as the corners & wing leading-edges of the F-22 Raptor. Note that early stealth planes like F-117 had much more extensive use of RAM, but this is reduced today given the increased usage of less conductive construction materials and superior, computer-assisted shaping designs.

How does RAM work? Once a radiowave hits a RAM-coated surface, the material absorbs the waveform, dissipating it's energy within the molecular structure of the RAM, so that very little energy, if any, goes back to wherever it came from. As a side-effect, when a RAM-coated surface is exposed to radar waves from extended periods, it heats up a lot (making your aircraft more easily visible to Infra-Red optical systems).



  • Radar-Absorbent Structures (RAS). These are entire structures/airframe components made out of materials which are inherently less reflective to radar. Like Carbon-Fiber Composites (CFC), Fiber mats, etc. which play a huge role in modern aircraft construction.

  • Serrated edges & other deflective structures. These are machined components designed to scatter and/or deflect a radar wave as it follows a surface, so that the wave doesn't make it to a part of the airframe which could reflect it back. You can find such serrations & saw-toothed edges on the surfaces of all stealth aircraft (and even some non-VLO aircraft like Rafale, as a means of reducing RCS).


Coming back to radar basics, it's important to remember that no matter how well your aircraft is shaped & coated, it still reflects a tiny amount of energy back to the radar. However all radars have a programmable Clutter-Rejection Threshold (CRT). This is a defining mark which stops the radar computer from reading every raindrop, bird & honeybee as a target - technically, even if a radar CAN see these extremely tiny signatures, it rejects them as clutter so as to reduce false alarm rates. In the following diagram you can see how a large signature stands out to a radar computer among many small signatures (the image is rendered to represent this and make it easy to present/understand, this isn't how a radar actually sees a target).



So as long as your aircraft's radar return is very small, the enemy radar won't register your presence and your signature will be lost among the various tiny signatures below the CRT -

 
Last edited:

Indian Sniper.001

Senior Member
Joined
Sep 22, 2016
Messages
1,454
Likes
6,737
Country flag
We keep hearing about missile tests. Now take for eg. India has Agni-V where the range is declared to be 5k kms (perhaps more), but they obviously can't test to the full distance, so what is the minimum distance for a missile test to be successful, and is the minimum distance different for cruise missile and ICBMs?
 

Latest Replies

Global Defence

New threads

Articles

Top