Military FAQ Thread

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aniket
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Re: FAQ Thread

Post by aniket »

What are those spike like things on the roof of the helicopter ?
http://www.copyright-free-pictures.org. ... l-huey.htm
nikhil_p
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Re: FAQ Thread

Post by nikhil_p »

^^^
IIRC it is something to do with Cutting wires, Wire Strike protection system.
Rahul M
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Re: FAQ Thread

Post by Rahul M »

FAQ Section 1 : Small arms

Contributor : ArmenT
The author also maintains an excellent blog on firearms which can be found at http://firearmshistory.blogspot.com/.


Q 1.1

Why is INSAS a semi-auto rifle only?

Because the Indian Army wanted it that way. This isn't the only rifle in the world that does this. The older 1A1 (the FN FAL clone) that was in service in India before the INSAS was also semi-auto only, as was the UK version of the FN FAL which the 1A1 was based off of. The US M16A1 is capable of full-auto fire, but was later replaced by the M16-A2 which is capable of firing 3 round burst at a time. So you can see that it isn't just the INSAS that works on semi-auto mode.

So why do so many military forces in the world supply their regular troops with semi-automatic only weapons? That's because of the US experience in Vietnam. They noted that less experienced soldiers generally tended to hold the trigger down and spray the bushes when they came under attack. As a result, many of them ended up using all their ammunition within a couple of minutes. To prevent this situation from occurring, regular troops were supplied with semi-auto only weapons and fully-auto weapons were only supplied to special forces units, who are well trained to use fire discipline.

Q 1.2
Why Indian army uses AK-47 in COIN, but not INSAS

First, not everyone carries an AK in COIN operations. Quite a few of the troops are equipped with INSAS or Tavors. Also, since real AK-47s are rare (as mentioned in the FAQ on AK family of arms later in this post), they are mostly carrying AKMs or type-56s. As to why they like them, the reasons are:
1. AKs require less maintenance and therefore suit the "grab your firearm and head out at odd times" nature of COIN ops.
2. While the INSAS has better accuracy, AK has better stopping power and automatic firing mode. Since most COIN ops happen at closer ranges, accuracy isn't as important.
3. AKs are capable of firing in full-auto mode which helps keep enemy heads down during COIN ops.
3. INSAS is the official rifle of Indian military and if one gets damaged during ops, the soldier has to fill up paperwork and explain the damage. AKs are recovered from terrorists and are considered as "unoffical weapons", so the soldier doesn't need to fill out the paperwork if one gets damaged.

Q 1.3
5.56 mm. vs. <your larger caliber here>


This is a question that there are a lot of arguments about. First we will start with some history. After World War II, Soviets unveiled a new firearm for soldier, the AK-47, which was designed to use 7.62x39 mm. bullets. This caliber was heavily influenced by developments of bullets of similar size in Germany. Meanwhile, NATO forces were using 7.62x51 mm. bullets, based on designs made by the US. Both these bullets pack a punch and have pretty good range. As it happens though, they also produce a good amount of recoil (especially the NATO rounds) and make a gun harder to control in automatic fire mode. One more factor to consider is that most people can't hit anything farther than 300 meters or so and therefore, giving them ammunition capable of firing well past this distance is not useful because they can't effectively use it. Additionally, the US military did some experiments in the late 1950s/early 1960s and determined that high rate of fire was the most important factor in infantry combat. To produce a high rate of fire means that a soldier needs to carry more ammunition. Therefore, the US military settled on a 5.56x45 mm. bullet, based on a .223 Remington cartridge that already existed. The 5.56x45 mm. NATO ammunition is close to half the weight of the 7.62x51 mm. ammo, therefore a soldier can carry twice as much.

As a side benefit, some people claimed that 5.56 is more likely to wound someone and therefore takes more than one person out of the fight because others have to tend to the wounded person's wounds and transport them to get medical attention. This was however NOT the reason why the 5.56x45 mm. was chosen, the main reason was because they could carry more of them. And, the 5.56x45 mm. is deadly at shorter ranges as well.

While the smaller bullet is fairly effective at shorter ranges, it loses some of its effectiveness at longer ranges. This is why some people argue that an intermediate bullet of 6.8x43 mm. might be a better compromise. It has effectiveness up to 500 meters or so and as it delivers about 50% more energy than 5.56x45 mm. at 100-300 meter ranges. However, it doesn't recoil as much as 7.62x51 mm. ammunition and provides better controllability. Also, since it isn't as heavy as 7.62x51 mm. ammo, a soldier can carry a good amount of them around.

Q 1.4
Which is better: M-16, AK-47, INSAS, Steyr etc.


Depends on who you ask. Rifle design is the art of striking a balance between various factors (e.g.) cost, accuracy, reliability, power, weight etc. and each country designs their rifle to their particular military's requirements.

For example, an AK-47 or other member of the AK family, such as AKM, AK-74 etc. are known for their reliability and ability to work in harsh conditions around the world, with very little maintenance. The Soviet military had a design competition where they specified that they wanted an assault rifle that should primarily be reliable in snow and muddy conditions, easy to manufacture with minimum factory requirements and also should be a simple mechanism which can be easily maintained by uneducated conscripts. These requirements were based on Soviet experience in World War II, where much combat happened in winter and muddy conditions and many soldiers were hastily conscripted from the ranks of poorly-educated peasants. Three different designers submitted their entries and while the other entries were better than the AK-47 in many other respects (lighter, cheaper, easier to control etc.), the AK-47 was more reliable and durable than the other two and that is why the Soviet military adopted it. This reason for the AK reliability is because of the wider tolerances between some moving parts and its long-stroke gas piston mechanism. This is why it is more tolerant to dirt, slush, dust etc. However, the very same features that make it more reliable also make it lose some accuracy and controllability in full automatic mode. The AK-47 and AKM also use a 7.62x39 mm. cartridge which is relatively larger and therefore packs a bigger punch.

Other rifles, such as the M-16, Steyr AUG, INSAS etc. are built to tighter specifications, which means they have better accuracy as the cost of some reliability. The assumption here is that the soldiers who use such rifles are trained professional soldiers and not hastily conscripted peasants and they will spend more time in doing proper rifle maintenance, which solves the reliability issue. They are also built to use a lighter 5.56x45 mm. NATO cartridge because the earlier NATO cartridge (7.62x51 mm.) was deemed too powerful for use by ordinary soldiers (i.e. hard to control the rifle because of excess recoil from a bigger cartridge and many people can't shoot accurately beyond 400 yards with iron sights, so why give them an over-powered cartridge). So while the smaller cartridge has a correspondingly smaller punch, it is also lighter in weight and therefore the soldier can carry many more of them. At ranges below 500 meters or so, the smaller cartridge is still pretty deadly. One more requirement for the US military was a higher rate of fire and the M-16 certainly shoots a good 15-35% faster than an AK-47 in full automatic mode. By the M16A2 version though, the US military decreed that automatic fire mode should be taken out of the M16 because too many fresh soldiers were wasting ammunition unnecessarily and hence the M16A2 is only capable of single-shot or three-round burst mode.

INSAS was also built to take 5.56x45 mm. NATO cartridges and was originally designed as a weapons system where a carbine, a standard rifle and a LMG could all be chambered to use the same ammunition and interchange many parts. INSAS was designed from the very beginning to have single shot mode and three-round burst fire mode only (just like M16A2 and unlike AK-47) because that's what the Indian military's specifications were (i.e. they didn't want soldiers to waste ammunition unnecessarily). INSAS's basic gas-operating mechanism has many features in common with the AK-47, with some features similar to FN-FAL (which was the basis of India's previous standard rifle) and some features influenced by Heckler & Koch's G3 rifle. It is also built to fire NATO standard rifle grenades. It doesn't have the firing rate of the M16, but is slightly higher than AK-47.

Steyr AUG was also built as a weapons system family: i.e. carbine, rifle, LMG where many common parts are shared. Like the M16, it was also designed to use the smaller 5.56x45 mm. NATO cartridge. The AUG family is unusual in that these rifles use a bullpup layout, which makes the firearms smaller and lighter to use. It has a translucent plastic magazine, a feature that the INSAS also has, so that the user can quickly tell how many bullets are left. It is also more expensive than the other rifles, but is used by a number of countries around the globe.

Q 1.5
What is the difference between AK-47, AK-56, AKM, AK-74, AK-101 etc.?


The AK-47 was the original assault rifle of the AK family of assault rifles. The design and development process started in 1946, but it was cleared for limited production in 1947 (hence, the designation 47 at the end of the name "AK-47"). They fired 7.62x39 mm. ammunition. The original AK-47 models were not really geared towards mass production. In particular, the receiver took a long time to make. The Soviets had originally tried making a stamped metal receiver made from sheet steel, but didn't have the technology then to make it properly and led to a large number of rejects. So they switched to a receiver made from forged steel which was milled into the final shape through various machining operations and hence it took longer time to manufacture. Early AK-47 (type-1) also didn't have chrome plated barrels or receivers, which were added later in AK-47(type-2) to increase resistance to corrosion

The AKM was an upgrade to the AK-47 and featured several improvements. The M in AKM stands for "Modernizirovanniy" (Russian word for "Modernized"). Design started in the 1950s and it was cleared for full production in 1959. The Soviets had acquired some mass production technologies from captured German engineers and these went into the AKM. The receiver on the AKM is made from a stamped steel sheet and like the AK-47 (type2), it has a chrome plated barrel and receiver. It also fires the same ammunition as AK-47. A number of improvements to the design contributed to better reliability and also capability of being mass produced. The weight was also reduced by 1kg and a simple muzzle brake (the slanted tip of the barrel) was added to counter the tendency of the muzzle to climb under automatic fire. Because of the ease of production, the AKM was exported to all the Warsaw Pact countries and several Asian and African countries and is very widespread.

AK-56 is the Chinese produced model in the AK family. It originally started being produced in China in 1956, as a direct copy of the AK-47 (type 1) model, but the Chinese gradually incorporated some of the improvements of the AKM (in particular, the stamped sheet metal receiver), as well as adding some of their own improvements. The official name of this is "type-56", but many people refer to this as the "AK-56". This is the most produced AK model around and the Chinese exported millions of these to various communist rebel movements around the world.

AK-74 is the model adopted by Soviet military in 1974 and still remains the rifle of the Russian military. This features use of plastic for some parts, in order to reduce weight and increase durability. One more big difference is that this fires 5.45x39 mm. ammunition instead of 7.62x39 mm. of its predecessors, as the Soviet military decreed this to be the new cartridge to be used by them. Because of this change of ammunition, a lot of the other parts are also changed to accommodate this new cartridge (e.g.) barrel, receiver, magazine, firing mechanism etc. Stock is changed to use laminated wood and later, polymer plastic.

AK-101 uses more plastic than AK-74. This is designed for export market and hence chambered to fire the NATO standard 5.56x45 mm. ammunition, which means the other parts are also modified to accommodate this ammunition. The AK-101 also has attachments to attach many telescopic sight models that are common in Europe and Russia.

Many times, when the news media refers to "AK-47s", they are most likely to be either AKMs or type-56 model, as true AK-47 models are actually very rare.

See: http://firearmshistory.blogspot.com/201 ... 7-akm.html for more details.

Q 1.6
What's with the slant barrel tip often seen on AKs being used by Indian forces? Are they wearing the barrels out or is it poor maintenance?


Neither actually. That slant on the barrel is deliberate. It is actually a simple device called a slant compensator. Basically, when a firearm is discharged, the barrel tends to rise upwards, due to the forces acting about the center of gravity of the weapon. The effect is more pronounced when the firearm in question is capable of automatic fire (like AKs are). To help keep the firearm on target, AKMs came with a compensator device. If you notice, the slant is pointed upwards and a bit to the right, because that's how AKs tend to move when fired, With the compensator in place, the exhaust gases leaving the rifle are directed upwards and to the right, thereby pushing the front of the barrel down and to the left, allowing the rifleman to more easily keep it pointed towards the target.

This simple device first appeared on AKM rifles and was backported to AK-47s as well, as the device is simply screwed on to the tip of the barrel.

See this discussion for more details: http://firearmshistory.blogspot.com/201 ... rakes.html
shiv
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Re: FAQ Thread

Post by shiv »

Rakesh wrote:
hnair wrote:HAPE is incredibly difficult to deal with at an individual level.
For all of you who do not know what HAPE means....enjoy!

http://en.wikipedia.org/wiki/High_altit ... nary_edema
These questions come up again and again on the China mil thread every few months. I had posted a series of articles on the problem that the Chinese military faces and what they are doing in the old china mil watch thread.

Will post them here too in one massive post (and will put them in the FAQ thread)

http://www.comhaha.com/blog/524004-f-11 ... -in-tibet/
PLA F-11 fighters flying over the exercises in Tibet.

LONDON August 10 report, according to Global Strategic Network 6 reported that the Chinese F -11 fighter flight training for the first time in Tibet. J -11 is the most advanced system of planes in China. Although 90 years since the last century, China is only less than 150 which built fighter planes, but they have appeared in many unexpected places. Reported that the Chinese Air Force planes stationed in Tibet is not, despite the old F -7 regular fighters often fly in the area, but mainly in large commercial airport, temporary assignments.

Report, said the past five years, the model of friction between China and Russia to become one of the reasons. In 1995, the price of 25 billion won from the construction of 200 Russian Su -27 fighter permissions. Russia is responsible for providing engines and aerospace electronic equipment, while the Chinese side is responsible for the drawings and specifications in accordance with the Russian construction of other parts. However, the construction of 95 Su -27 fighter, the Russian side to cancel this agreement. Russia says China has used Su -27 fighter procurement project from the knowledge gained, the construction of its replica of the Soviet Union -27, that is, F -11 fighter. Russia warned that China simply copy the Russian technology, can build a low-quality aircraft. Obviously, China does not think so, its use of technology to the development of the Chinese fighter J--11.

It is believed that F -11 fighter is now more advanced equipment, including aerospace electronic equipment and some other Chinese design improvement. China to produce F -11 fighter most of the parts, the main problem is its still has to import engines. China believes that in the next five to ten years, it will get rid of dependence on Russian military aircraft engines. At present, China imports two Russian engines - priced 3.5 million U.S. dollars of the AL-31 (Su -27/30, F -11, F -10) and Unit 2.5 million U.S. dollars of the RD-93 (MiG -29 dispensed RD-33 engine in a version).

Reported that the People's Liberation Army Air Force fighter planes stationed in Tibet is not the main reason was the region's high altitude, large quantities of fuel costs as well as in Tibet and other supplies required for the maintenance of aircraft. At present, only one railway to Tibet (made recently built), and one of the few passable roads for heavy trucks.

Moreover, the PLA officers and men of altitude sickness in Tibet is the Chinese presence in Tibet fighters to a major problem. When people who grew up from the plain areas (most of the world population is so) migrate to the high mountain areas, will be insufficient oxygen due to air in such a reaction occurs. This "mountain sickness," the main symptoms of shortness of breath, a sense of direction, confusion, nosebleeds, nausea, dehydration, decreased quality of sleep and eating problems, headaches, etc., if there is "Altitude Sickness" and stay at altitude for too long time loss of labor force will slow.

Reported that the average altitude of Tibet 4100 meters. Most people can adapt to local environment, but some people can not. Most of the soldiers came to the Tibetan plateau need to spend a few days or weeks to adjust to the local environment. But if they overworked, especially long exertion, still prone to altitude sickness. This has weakened the combat effectiveness of the Chinese troops stationed in Tibet.

Researchers recently found that in the past 3 1000-6 thousand years, Tibetans have evolved to adapt to this environment. The reason these people will become the main inhabitants of Tibet, mainly because they are more robust at high altitudes. Almost all Tibetans have this gene (control red blood cell activity, to maintain adequate oxygen levels). Low elevations, but very few Chinese people these genes.

Reported that the Chinese army is now putting in a lot of time, money and effort to solve this problem. Now, most of China's Chengdu Military Region, troops are deployed in the basin of the eastern half of the points. In Chengdu, western Tibet, China has deployed 52 and 53 Mountain Brigade, and strive to maintain the ability to perform tasks of 5,000 troops. The event of emergencies, like two years ago, as 13 and 14 near the army to its base in the lowlands to send troops overseas. However, once reached heights of more than 20% of soldiers are suffering from high disease, leading to disruption of work, but commanders have been trained to adapt to this situation.


Now, based in the plateau (the Sino-Indian border highland 4,500 meters) of the Chinese troops have the training room, training room in one of 1,000 square meters, and another 3,000 square meters, the training room are in oxygen-rich state. In the training room for training of soldiers, soldiers of the body can increase the oxygen content in the blood and reduce the prevalence of risk of altitude sickness. In this way, the soldiers deployed there can stay healthy. In addition, the Department of soldiers in high altitude patrol the border areas, usually carry oxygen bottles and breathing masks.

However, so far, China can only alleviate altitude sickness, not eradicate. Taking into account the aircraft maintenance personnel awareness of requirements, and the pilots prepare for flight, coupled with logistical problems, the PLA Air Force has announced timely training in Tibet, but not the air force deployed there. However, perhaps one day the Chinese Air Force will have to fight over in Tibet, so they should be there for related training



http://www.uyghurnews.com/tibetan/Read. ... 0611109346
China builds oxygen-rich barracks for soldiers in Tibet

Saibal Dasgupta, TNN
Times of India
June 27, 2010

BEIJING -- The People's Liberation Army in Chinahas come up with the first batch of ecologicaloxygen-enriched barracks for use by troops postedin the oxygen deficient mountain regions of Tibetacross the Indian border. It means lesserdependence on oxygen cylinders and higherperformance for soldiers, the PLA research team has reported.

This is one of the several recent innovations reported by Chinese defense establishment that include reduction in take-off time for ship-based helicopters, reorganizing the layout formulti-functional training ground in the slopes ofInner Mongolia and running digitalized medical services, according to the official media.

Oxygen enriched barracks built at a height of4,500 meters at the Naqu Military Sub-Command inTibet involved using plants to generateadditional oxygen in a special activity room andbarracks with floor space of 1,000 square metersand 3,000 square meters, respectively. Soldiersusing these facilities during exercise were foundto have 10% higher oxygen level in the blood ascompared to the outdoors and relieved of the problem of plateau anoxia.

The harsh environment with 48% oxygen as comparedto the hinterland has been a cause of worry forthe PLA, which found a large number of soldierssuffering from altitude diseases as alopecia andnail dent. Ecological experts including botanistsand altitude disease pathologists were brought infor an on-the-spot investigation in the largelyunpopulated area. This is what resulted in thecreation of barracks that use plants to generateadditional oxygen, the official media said.



http://www.eso.org/sci/facilities/alma/ ... ode25.html
the key to reducing the negative effects of high altitude will be the provision of oxygen enrichment in the site buildings and other enclosures such as transporter vehicle cabins and antenna receiver cabins, and the use of lightweight portable oxygen units where appropriate. An increase in the oxygen concentration in the buildings from the natural value of 21% to 26% will provide workers with an environment equivalent to that at an altitude of 3500m, which should be acceptable. The choice of 26% is a compromise between competing requirements: improved performance would be achieved with a higher concentration, but it would reduce the degree of acclimatization for indoor workers who must also work outdoors, and it would increase the cost and fire hazard. Oxygen enrichment is now feasible and economical because of the availability of molecular seive technology - it is no longer necessary to use liquid oxygen in bottles. The effective annual cost of oxygenation in a two-man office is about $500 per worker, a small fraction of an annual salary, and it would be still more economical if used on a larger scale. Oxygen enhancement produces an increased fire risk, which is particularly dangerous at high altitude because of the increased risk of asphyxiation. Inhaled smoke decreases an already diminished oxygen supply, so the time required for evacuation is reduced. In addition, the reduced oxygen causes combustion to be less complete, increasing the levels of carbon monoxide. Thus, special care must be taken in the design of the buildings, to provide adequate smoke detection sensors and emergency exit routes. The proposed oxygen concentration of 26% is within accepted standards (including those for the Space Program), and will not cause an unacceptable fire hazard.

For outside workers, particularly those who must perform tasks which are mentally or physically particularly demanding, portable oxygen units will be available and their use should be required. A light weight, back mounted oxygen tank feeds a nasal cannulas. With an oxygen supply rate equivalent to an altitude of 3500m and by using a demand regulator which supplies oxygen only when the user breathes in, a system weighing only 4 kg will supply oxygen for more than eight hours. A nasal cannula is preferred over a mask because it makes communication easier and is less intrusive. Such portable devices are widely used by medical patients and have been used for research and mining work at high altitude.



http://www.strategypage.com/htmw/htatri ... 00710.aspx
Researchers recently discovered that most Tibetans evolved in the last 3-6,000 years to deal with this problem. It appears that the most of the people moving to, and staying in, highland Tibet, where those with the rare genes that made them resistant to altitude sickness. These people became the dominant population in Tibet, mainly because they were healthier at high altitudes. Nearly all Tibetans have this gene (which controls how their red blood cells operate, to maintain sufficient oxygen levels). Very few lowland Chinese have these genes.

The Chinese military is spending a lot of time, effort and money trying to solve this problem. Currently, most of the troops in the Chinese Chengdu Military Region are in the eastern, lowland half. In the western portion (Tibet), they station the 52nd and 53d Mountain Brigades, and struggle to keep these 5,000 troops fit for duty. If there's an emergency, as there was two years ago, the nearby 13th and 14th Group Armies can send troops from their lowland bases. Over 20 percent of these troops will be hampered by altitude sickness once they reach the highlands, and commanders are trained to deal with that.

Chinese troops operating at the highest altitudes (4,500 meters, on the Indian border) now have access to exercise rooms (one of 1,000 square meters and another of 3,000 square meters) that are supplied with an oxygen enriched atmosphere. Troops exercising in these rooms increase the oxygen in the blood, and are much less likely to get hit with a case of altitude sickness. Thus the troops can stay in shape without getting sick. For border patrols at high altitudes, troops usually carry oxygen bottles and breathing masks.

So far, the Chinese have only been able to limit the attrition from altitude sickness, not eliminate it.


http://news.xinhuanet.com/english2010/c ... 259413.htm
BEIJING, April 20 (Xinhua) -- Altitude sickness poses the biggest challenge for rescuers from the military and armed police in their quake-relief efforts in northwest China's Qinghai Province, a senior military officer said Tuesday.

Wang Zhenguo, an officer with the Yushu quake-relief headquarters of the Chinese People's Liberation Army (PLA) and armed police, said at a press conference that no casualty had been reported among the quake-relief soldiers and armed police so far despite the difficulties.

However, all quake-relief soldiers and armed police suffered altitude sickness including dizziness, short of breath, fatigue and coma, said Wang.

Two soldiers had pulmonary edema after catching colds and were being treated in hospital, he said.

But the majority of the quake-relief soldiers only had slight symptoms such as dizziness and short of breath as most of them were young and had previously participated in military tasks on plateaus, according to officers attending the press conference.

To cope with altitude sickness, most of the soldiers were told to carry more medicine as well as oxygen concentrators and tanks, Xie Weikuan, an officer with the PLA General Logistics Department, said at the same press conference.

As of Tuesday, the PLA General Logistics Department had supplied 5,000 portions of medicine, 100 oxygen concentrators and 145 oxygen tanks to help soldiers cope with altitude sickness, Xie said


Image
http://www.business-standard.com/india/ ... s/39474/on
Army to induct cost-effective indigenous Hapo bags
Press Trust of India / Jammu June 07, 2008, 16:17 IST

Cost-effective indigenous Hapo (High Altitude Pulmonary Oedema) bags will soon replace imported ones in Jammu and Kashmir's Ladakh sector, Defence sources said today.

Each imported bag costs Rs 15-20 lakh while its Indian counterpart, developed by Bangalore's Defence Bioengineering and Electromedical Laboratory last year, costs only Rs 1 lakh.

An order has been placed for 3,000 such bags from manufacturers in Kolkata, Barkhi in Pune and Revari in Rajkot following successful field trials in the Khardungla and Siachen — some of the highest glacier belts in the world.

"A batch of 1,300 Hapo bags will reach Armymen in J&K soon," Lt Col S D Goswami said. "In the first phase, the portable one-man lifesaver would be deployed in Siachen, Kargil, Dault-Beigh-Oldi, Chashul, Leh and Kashmir plus some counter-insurgency areas in North-East and Pirpanjal range."

A Hapo bag typically absorbs carbon dioxide from the body of a patient suffering from pulmonary oedema, a condition in which water accumulates inside his lungs, by increasing surrounding temperature and pressure and pumping in oxygen.
shiv wrote: Erythropoietin is the hormone in the body that causes an increase in oxygen carrying red blood cells during high altitude acclimatization.

Maybe there is a business opportunity there. Here are the world's Erythropoietin producing companies. Mostly SDRE
:mrgreen:

http://en.wikipedia.org/wiki/Erythropoi ... iomedicine


* Epogen, which is made by Amgen
* Epotin, which is made by Gulf Pharmaceutical Ind. (JULPHAR)
* Betapoietin, which is made by CinnaGen and Zahravi
* ReliPoietin, which is made by Reliance Life Sciences Pvt. Ltd
* Erykine, which is made by Intas Biopharmaceutica Pvt. Ltd
* Shanpoietin, which is made by Shantha Biotechnics Ltd
* Zyrop, which is made by Cadila Healthcare Ltd.

ramana
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Re: FAQ Thread

Post by ramana »

Shiv, I saw on Discovery Channel a few years ago that research on Incas also showed they had some rare genes which made them immune to high altitude sickness.
shiv
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Re: FAQ Thread

Post by shiv »

Origins of Bundaar

In the late 1980s when Osama bin Laden was a great freedom fighter, the Chinese and the Americans were thick as thieves. China contracted Grumman corp to help her upgrade Chinese MiG 21 clones (called F-7) to create a super MiG 21 called "Super -7". What Grumman did was to put a nose cone on the design and move the intakes to the side. The nose cone of the "Super-7/Grumman Sabre II" was to house the radar of the F-20 Tigershark. Grumman was clearly playing with its own ideas about the F-5/F-20 and was trying to sell it to various nations. You probably know hat Grumman tried to palm off the F-20 to India. A sale of F-20s to Taiwan was blocked by the US government because the Chinese would get upset and get their kimkoms in a twist.

Here are photographs of the designs of Super-7/Saber-II.

Click on the image below to see the original Grumman Sabre II design, and the Super-7/FC-1 project that came later.

Image

The Sabre-II retained MiG 21s Delta wing but from the front the design looks pretty much like what the Thundaar does today. But Grumman had to pull out because of the Tiananmen love fest. But not before they had shared ideas with China, which went on and started what was called the FC-1 project that later became the Thundaar JF-17. The FC-1 retained the nosecone of the Super-7/Saber II/F-5 and the front profile looks very similar.

But what the Chinese did for the FC-1 was to change the classic MiG 21 delta to the delta with relatively shorter chord (and longer wingspan) that we see on the Bundaar as can be seen in the head on front views in the image above.
shiv
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Re: FAQ Thread

Post by shiv »

Indian names of aircraft:

Dassault Ouragan - Toofani
HF-24 Marut
HJT 16 Kiran
HPT 32 Deepak
HAL HAOP Pushpak
HAL HAOP Krishak
Alouette II Cheetah
Alouette III Chetak
Mi 8 Rana
Mi 17 Pratap
Jaguar Shamsher
IL 76 Gajraj
AN 32 Sutlej
Mirage 2000 Vajra
MiG 21 upg - Bison
MiG 23 Rakshak
MiG 27 Bahadur
Mig 29 - Baaz
ALH Dhruv


Aircraft with no special names AFAIK

Vampire
Hunter
Mystere
Canberra
MiG 21 earlier versions
HS-748
Iskra
Harvard
Dornier 228
Alize
Seahawk
Su-7
Su-30
Rahul M
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Re: FAQ Thread

Post by Rahul M »

mig-21FL possibly upto bis, trishul

mig-25 garud

this practice was discontinued from su-30mki onwards.
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Re: FAQ Thread

Post by merlin »

Rahul M wrote:mig-21FL possibly upto bis, trishul

mig-25 garud

this practice was discontinued from su-30mki onwards.
Practice discontinued for non-Indian aircraft. LCA is Tejas since its Indian.
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Re: FAQ Thread

Post by Bala Vignesh »

Another oft asked question in the LCH dhaga is "Why can't we add a gatling gun in lieu of the 20mm canon to the LCH??" or variations thereof.

The answer is simple for 2 reasons: Weight and Recoil

The Weight of a gatling gun of the same caliber is usually almost equal to or more than double the weight of the canon (M61A2 Vulcan weighs 92Kgs without the feed system, while the M621 canon weighs 46Kgs). So for a weight limited bird, to carry an useful payload at Himalayan altitudes, the canon is a better choice.

The second reason is the recoil generated by rapid firing of the gun, the raison d'être, for this kind of gun will generally push a hovering helicopter around. And this effects the grouping of the shots, making the weapon almost ineffective. The canon however can group shots more accurately and can fire of longer bursts on target.
Refer the recoil force of a M61 vulcan 20mm gatling canon here and the recoil force of a Nexter M621 20mm canon here.
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Re: FAQ Thread

Post by rajanb »

Bala Vignesh wrote:Another oft asked question in the LCH dhaga is "Why can't we add a gatling gun in lieu of the 20mm canon to the LCH??" or variations thereof.

The answer is simple for 2 reasons: Weight and Recoil

The Weight of a gatling gun of the same caliber is usually almost equal to or more than double the weight of the canon (M61A2 Vulcan weighs 92Kgs without the feed system, while the M621 canon weighs 46Kgs). So for a weight limited bird, to carry an useful payload at Himalayan altitudes, the canon is a better choice.

The second reason is the recoil generated by rapid firing of the gun, the raison d'être, for this kind of gun will generally push a hovering helicopter around. And this effects the grouping of the shots, making the weapon almost ineffective. The canon however can group shots more accurately and can fire of longer bursts on target.
Refer the recoil force of a M61 vulcan 20mm gatling canon here and the recoil force of a Nexter M621 20mm canon here.
Thanks Cap'n Bala. Informative.
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Re: FAQ Thread

Post by Rahul M »

balaji, would you mind putting it in BR wiki ?
thx.
http://bharatrakshak.wikia.com/wiki/Bharat-rakshak_Wiki

merlin sahab, not to counter your point but LCA is not a good example. it was named by ADA, not IAF.
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Re: FAQ Thread

Post by Bala Vignesh »

Rahulda,
Could you please guide me on how to do this??? I have not used wiki till date so don't know my way around in that is all..
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Re: FAQ Thread

Post by Rahul M »

please check PM.
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Re: FAQ Thread

Post by shiv »

When it comes to laying down intense firepower over an area, multiple rockets from pods are as deadly, if not more than a Gatling weight for weight. I had made this combo video to try to illustrate that.
http://www.youtube.com/cybersurg#p/u/7/VuLnnVDld-M
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Re: FAQ Thread

Post by Bala Vignesh »

Rahulji,
Is it okay if put the whole FAQ section in the BR Wikia page???
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Re: FAQ Thread

Post by Rahul M »

sure
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Re: FAQ Thread

Post by hnair »

shiv wrote:When it comes to laying down intense firepower over an area, multiple rockets from pods are as deadly, if not more than a Gatling weight for weight. I had made this combo video to try to illustrate that
And the user can select what round they want to unleash, unlike the gun. Plus with wind correction algo and some cheap imaging add-on kits (as khan was trying out with the venerable Hydra/Zuni family, the APKWS program), these things can get better accuracy than a gun at maximum range. Also these pod-fired systems needs minimal maalish-paalish at forward bases compared to complex gun-systems. Infact if they can have a pair of slewable pod-turrets (under chin to prevent backlash from launch), these things can fire off bore, with laser guidance.

But they are SDRE priced compared to TFTA priced Hellphyr and hence non-kosher for khan's contractors. So every Alky#3 deserves 1.x million USD on his head, instead of 1/10 that 8)
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Re: FAQ Thread

Post by shiv »

We had a discussion earlier whether one can or cannot see flame in a non afterburning jet exhaust. I know you can if you look directly from behind, especially at higher power settings. but videos are few and far between because no one can actually stand behind one to video it. But such videos do exist, and you can see flame in the exhaust of a non afterburning jet pipe. But you need to get directly behind and look inside.

http://www.youtube.com/watch?v=OvXcIFQHlgc
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Re: FAQ Thread

Post by shiv »

Hitesh wrote:How did you fix it?

I had the same problem when I tried to post youtube videos and all it showed was a big empty white of space.
How to post the following video as an embedded video on BR
http://www.youtube.com/watch?v=HvioAKTyK_4

Step 1: Click on the "youtube" box above the reply box to insert the code which looks like this: [you-tube][/youtube]

Step 2: paste the link in the space between the two words of the youtube code like so
[you-tube]http://www.youtube.com/watch?v=HvioAKTyK_4[/youtube]

Step 3: remove all the stuff starting from "http" up to the "=" sign, leaving only the video code; Remove the stuff shown in red below:
[you-tube]http://www.youtube.com/watch?v=HvioAKTyK_4[/youtube]

Step 4: Click "submit"

There you have it: 8)

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Re: FAQ Thread

Post by PratikDas »

shiv wrote:
HAHAHA! This is hilarious! :rotfl:

Is that your voice, Shiv ji? How did you not laugh?
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Re: FAQ Thread

Post by shiv »

This post from a former MiG 21 pilot of the IAF certainly needs to go on here
aharam wrote: That said, it was quite a bit of fun while it lasted. At the time, the primary focus was on WVR and merges, and that's what we were trained in. In that role, the Mig 21 was an excellent plane. Very light, beautiful turn characteristics - much like driving a sports car. It is not a forgiving plane and was designed in an era, where much more pilot attention had to be focussed on the basics. No FBW, so you had the whole flight envelope to yourself. This also meant that you had to be very careful with an aircraft that had its CG well aft of the pilot. You could into a deadly flat spin in certain stall conditions. In my years, I don't recall it being a "flying coffin" as it is termed now - you had to careful, it was drilled into us and training did involve recovery from various stall geometries. If you paid attention, it was not a dangerous plane per se. Then you get into a phase, where you are far more comfortable with the aircraft, so much so that regular sorties feel like a drive to the grocery store - albeit a fast drive :-). That's the dangerous part, because the plane is unforgiving of mistakes and when you get too comfortable, you are apt to miss something. When I see the crash statistics now, I am not sure if it is the pilot or the plane. The airframes are quite old now and maintenance was always an issue. In my time, each plane in the squadron was unique in that something about the feel was different, either the flight envelope, handling or even something as small as a nose wheel shimmy on landing or takeoff forcing you to keep pressure off of it. As the plane ages, these can get exacerbated and can cause crashes. Another possibility is simply that training is focussing more on FBW, where the flight envelope is determined by the computer, which has it own limit settings to ensure that you don't deviate. Much safer, but once you get used to no envelope restrictions, I don't know how FBW would feel - I never flew an FBW fighter, so I can't compare.

The Mig 21 certainly belonged to another era of fighter design. Light and agile. I don't know if folks here have read John Boyd's work on maneuverability, the 21 was the epitome of it. The agility of a plane is not just its specs - turn radius, climb rate, thrust/weight ratio. In WVR, it has much more to do with how rapidly you can change the attitude of the plane, for instance changing the direction of a roll. A plane that can rapidly switch from one position/attitude to another without losing much energy holds an advantage in a merge, since it can engage and disengage at will. That was the real fun of a lightweight interceptor. With heavy class fighters, particularly with TVC, although they can turn and climb very rapidly, I am not sure how many attitude/position transitions they can go through without losing significant energy. Energy is still critical at the end of the day - it is what you can accomplish with a given amount of energy that determines the better plane. All of this of course assumes identical pilot skills, which is generally not the case. With most engagements now in the BVR regime, I am not sure if the WVR regime is that important, which is why the 21 is from a different era. Small highly agile light fighters are not there any more and probably not needed in a networked environment where the aircraft is a delivery platform. Even the vaunted F16 is a lot heavier than when it started, and I am not sure it will really keep its edge in the presence of a competently flown 21 in the WVR regime.
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Re: FAQ Thread

Post by shiv »

Another FAQ-worthy post
aharam wrote:
srai wrote: According the the infamous presentation video of a USAF officer speaking on the topic of Red Flags, Su-30MKIs and F-22 Raptor, he mentioned that if the fighter with a TVC uses it beyond the lift dynamics of the aircraft the plane begins to sink rapidly while pivoting in the air. The opponent fighter seeing this will need to use his energy advantage by pulling up and then coming down for a kill with AAM or guns.
That is the conundrum of fighter performance. These days the focus is on multi-role aircraft. So the weight increases to support the various roles, some of which are as disparate as A2A and A2G. As weight increases, you need a heavier engine with higher thrust. In A2A, while you may have higher thrust, you are not just going straight. Combat maneuvers cause rapid change of position, and in a heavier plane you lose energy very rapidly. Essentially, you are using your engines to change your momentum vector rapidly and for a heavier plane, even the excess thrust is not sufficient to compensate for this. A lighter plane may not have the thrust to do a cobra - beyond a certain AoA, 21 falls on its back :-), but the 21 doesn't have the weight either. It can do several rapid rolls in opposite directions without losing a lot of energy and that gives you a lot of options in a dogfight. I believe even the F22 is too heavy to sustain a dogfight against a lighter plane. It can do so against an F15, but the F15 is overweight, so a victory doesn't count for much. Even the F16 started off as a much lighter platform and gained over the years, which detracts from its original design.

A good analogy here is a comparison between two sports cars in a slalom course (windy road). One is lighter, but has a smaller engine and the heavier one has a beefier engine. Both have the same engine HP per ton of weight. Which do you think is going to win a time trial? Even if you made the contest unequal and gave the heavier car somewhat better HP per ton of weight it would still lose on a slalom. It will win a straightaway course, but the constant twists in a slalom decelerate it too much on each turn for it to recover its energy position. A dogfight is a slalom.

Most likely a moot point in today's BVR environment :-)
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Re: FAQ Thread

Post by member_20010 »

I have written a piece "Contours of a Possible Indian Riposte to Future Chinese Agrssiveness" the piece is rather long- around 5000 words. Can I be guided on how to post this piece ? thanks
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Re: FAQ Thread

Post by shiv »

Some quotes from this article belong in the FAQ thread because the reasons for "time lags" in complex technology rich (for the country) programs seem to be unknown to educated jingos

It's about the JSF/F-35
http://www.aviationweek.com/aw/blogs/de ... d=blogDest
When the Joint Strike Fighter team told Guy Norris about the jet's first run to its Mach 1.6 design speed, a couple of minor facts slipped their minds. Nobody remembered that the jet had landed (from either that sortie or another run to Mach 1.6) with "peeling and bubbling" of coatings on the horizontal tails and damage to engine thermal panels. Or that the entire test force was subsequently limited to Mach 1.0
Experience from flight testing has eviscerated the argument ...that modeling and simulation had advanced to the point where problems would be designed out of the hardware. In fact, the F-35 is having just as many problems as earlier programs
Since flight testing started to pick up speed in June 2010, 725 engineering change requests have been initiated, of which 148 are ready to incorporate. On average, it takes 18-24 months between the identification of a change and its implementation in production
The underwing fuel dump system on the JSF doesn't get fuel clear of the aircraft surfaces, so that fuel accumulates in the flaperon and may get into the integrated power package (IPP) exhaust. That creates a fire hazard,
F-35 flight tests have not gone beyond 20 degrees angle of attack, and higher-than-predicted buffet loads have been experienced. So far, severity has been similar to current aircraft but it is experienced over a large part of the envelope. Exploration of the high-AoA envelope does not start until the fall of 2012 and full results will not be available until 2014. Excess buffet can accelerate airframe fatigue, and induces jitter in the HMD.
Today, the killer problem with EO-DAS is latency: the image in the helmet lags 130 milliseconds behind sightline movement where the spec is under 40 ms. (So the video is where the pilot's head was pointed an eighth of a second ago.) That can't be fixed without changing the JSF's integrated core processor - the jet's central brain - and the EO-DAS sensors.
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Re: FAQ Thread

Post by ramana »

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Re: FAQ Thread

Post by Kanson »

LCA TEJAS :: PITCHING MOMENT COMPENSATION ON DEPLOYMENT OF AIRBRAKES AND LESSONS LEARNED
====================================================================

Image
Image
Image
Image
Image

SOURCE: http://nal-ir.nal.res.in/5012/1/INCAST_2008-083.pdf
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Re: FAQ Thread

Post by PratikDas »

Thank you, Kanson. That was an excellent read even when glossing over the matrix manipulations. Please correct me if I'm mistaken but the paper stops short of declaring the pitching moment problem resolved. What did you infer?
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Re: FAQ Thread

Post by Kanson »

You are welcome, Das. Section 3 & 4 do say solutions were provided. Section 3 last line mentions Aero tables were updated from resultant study and Section 4 reports feedback loop gain was increased to compensate for the sideslip, wrt Airbrake position.
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Re: FAQ Thread

Post by PratikDas »

Thanks. I did note those changes.
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Re: FAQ Thread

Post by Craig Alpert »

Not sure where to post this, but are ppl having problems acessing BR homepage? I can access the forums but not www.bharat-rakshak.com ? Admins care to share what's up?
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Re: FAQ Thread

Post by yantra »

^^ It has been so for days now! Whats up?
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Re: FAQ Thread

Post by Kanson »

% of Composites used in LCA Tejas:

Image

45% by Structural weight.

90% & above by Surface Area.

Source: Composites Manufacturing Division, HAL.
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Re: FAQ Thread

Post by shiv »

I think that one perspective that is missed when we talk of aircraft design is how history has played a role in such a way that each new development in flying is based on an earlier improvement. This has been a continuous chain of innovation going back more than a century to the first aircraft that were built.

The earliest aircraft that flew were not designed for amy military requirement. They were recognized as being useful by militaries for reconnaissance. Early military aircraft had a man with a bomb to be thrown by hand in the open back cockpit or a man witha gun. This was clearly so unsatisfactory that militaries looked for better armament.

The next step was (IIRC) the machine gun in a gunner's cockpit. But by the time this innovation came, aircrfat were already flying. The basic design, the engine, the materials etc were already known. Adding a gun added complications that were made easier if you already knew how to build a plane.

The next step in evolution was the forward firing machine gun. One idea was to have a pusher propeller to bypass the problem of firing through the propeller. But I think it was the Germans who came up with a timer that mechanically linked the gun to the propeller so that the gun would not fire when there was a prop blade in front of the barrel. By the time this complexity was added, they knew how to build flying aircraft and design them to fly with the extra weight of guns.

Further steps would be the development of ways of carrying underslung bombs and releasing them. These would have require new designed with strengthened wings. So by the time world war 2 came - all the European and American (and japanese) companies had solved these initial issues. Tens of thousands of planes had been built by tens of thousands of engineers and factory workers at a time when India had just a handful of engineers of any kind.

The fierce fighting and research and numerous production lines set up for world war 2 spurred new aircraft designs, armament, radar and jet engines. By the time WW2 ended the warring nations were past masters at building reliable flying aircraft with reliable engines. The newest post WW2 designs used the old knowledge of aircraft with the new jet engines. By this time India had HAL, but it was under American control during WW2 and was mainly overhauling and repairing.

By 1951 HAL had designed its own first aircraft - the HT-2 which was apparently modern in capability as a basic trainer but in reality its power, performance etc were not even equal to that of a German Me-109 built in the mid 1930s. In contrast the Canberra bomber was entering service in Britain in 1951. Can you picture the technology gap between HT 2 and the Canberra? And the HT-2 had an imported engine of course.

The HF 24 first flew in 1961. Although it was a big achievement for India, compare with what was being done in Europe and USA: The Alouette II that we still fly flew in 1957, An 12-1957, Vulcan Bomber 1956, Boeing 707 1955, B-52 in 1955, KC-135 in 1956, Ouragan 1952, Dassault Etendard (just retired or about to be retioted French navy) 1958, Mirage III, (still in service) 1956, A-4 Skyhawk 1956 the list is in the link below - see for yourself and check the tech capability gap.
http://www.militaryfactory.com/aircraft ... 0-1959.asp
Heck MiG 21 was 1959!!

By 2015 we will have the LCA in service. The MiG 21 will just have retired. The Mirage III may have retired. The B 52 will not have retired. But the Tejas uses technology similar to the F-16 and Mirage 2000. The F-16 entered service in 1978 but I would rate the Tejas as probably having newer flight control and other tech than the early F-16s. The Mirage 2000 entered service in 1982.

If you look back you find that France took from 1956 to 1982 (26 years) to graduate from HF-24/Mirage III level to Mirage 2000. The US did the same leap from Skyhawk (1956) to F-16 - 1978 - 22 years. But both countries had been building engines from the 1800s and jet engines soon after they were invented. India has taken 50 plus years to graduate from HF-24 to Tejas. But the US and France already had 50 years of experience to reach the Skyhawk/Mirage III level. India got there in 10 years - minus the engine tech. It was surely the Kurt Tank effect.

Still, if you look at the history of the last 60 years of Indian aircraft manufacture, we remain about 30 years behind the top countries of the world in technology. We are of course decades ahead of many countries who are incapable of doing what we have done, but if choose to compare ourselves with the top 3, then we are anywhere from 20 to 35 years behind. From the early years of aviation around 1900, the US and France took about 80 years to reach F-16/Mirage 2000 level. India's "early years" started in 1950 and we have taken about 65 years to get to F-16/Mirage 2000 level.

It is worth remembering that countries like Britain and the US have probably had more accident deaths from test flying since the early 1900s than the total number of test pilots ever trained by India. And the US, Britain and Germany, probably had more aircraft engineers working in 1940 than we have in 2012.

So when you compare, please be aware of the history of your own country. People who work in Indian industry do not deserve contempt. They deserve support so that they too can work, make mistakes and learn. No one will teach us any other way. As a nation we have been so enamoured of foreign tech that we have been fooled into thinking that the people who are 30 years ahead will just give is the experience they have. You cannot transfer experience. "Deep" technology transfer, an expression that we on BRF went ga ga over a few years ago means little. We just have to learn the hard way.
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Re: FAQ Thread

Post by Mihir »

This post was prompted by what shiv wrote in Shiv in the China Military Watch thread:
If you can show me photos of any other engine that produces that characteristic blue afterburner flame I would say that the J-20 uses something different. There is something unique about that mix of gases coming out the back of an Al 31 that creates that flame. I have never seen that with any other engine.
Note that the the Tu-22M3's NK-25 and the B-1B's F-101 engines also produce a blue flame when on reheat.

The basic principle of an afterburner is simple: fuel is sprayed into the exhaust gases leaving the nozzle right after the turbine. The exhaust contains a large quantity of excess air, which makes combustion of this fuel possible. The result is that the exhaust is accelerated to a higher velocity, producing extra thrust. As the fuel injected into the exhaust gas stream burns, a visible flame is produced. The question is, why do some engines produce blue flames, while others produce yellow ones?

A yellow flame is characteristic of a rich fuel mixture. If you spray more fuel into the exhaust gases than what can undergo complete combustion, it leads to soot formation in the flame, giving it the characteristic yellow colour. On the other hand, using a leaner mixture with oxygen premixed in the fuel causes the fuel to burn completely, producing a blue flame. You can replicate this using a Bunsen burner. There are air inlets in the bottom of the burner that can be opened or closed. If you keep them closed, combustion is incomplete and you get a yellow flame. Open the holes, and air is sucked into the base of the burner, where it mixes with the fuel and ignites at the top, producing a blue flame. This is illustrated very well in the picture accompanying this article on Wikipedia.

Since a lean mixture wastes no fuel, it is obviously more efficient, but that efficiency comes at the cost of reduced thrust. Remember that the maximum thrust an afterburner can produce is limited by how much airflow is available. Design your afterburner to spray more fuel than can be fully combusted, and you are maximizing the thrust produced, but are wasting fuel and producing soot. Spray less fuel, and you aren't producing as much thrust as you potentially could, but you end up with a set-up is far more fuel-efficient. It seems sensible that the designers of an intercontinental bomber or a long-range fighter would choose to sacrifice thrust in favour of a more fuel-efficient afterburner, while the designers of a light/medium fighter would want to eke out as much thrust as possible from the engine, as a tiny difference in thrust could mean the difference between life and death, between success and failure against an opponent in an equally agile fighter.
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Re: FAQ Thread

Post by skher »

Saar, would like to procedure to delete account.It is not what it was it used to be -There was a clearly marked delete account earlier.
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Re: FAQ Thread

Post by koti »

After how many posts will I become an BR Oldie?
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Re: FAQ Thread

Post by shiv »

koti wrote:After how many posts will I become an BR Oldie?
skher wrote:Saar, would like to procedure to delete account.It is not what it was it used to be -There was a clearly marked delete account earlier.
Please post these Qs in the newbie thread.
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Re: FAQ Thread

Post by ramana »

koti
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Re: FAQ Thread

Post by koti »

Can anyone tell me how I can rename the thread I created.
TIA.
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