International Aerospace Discussion

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renukb
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Re: International Aerospace Discussion

Post by renukb »

Air Weapons Article Index : Will It Work?
http://www.strategypage.com/htmw/htairw ... 81020.aspx

October 20, 2008: The biggest question mark in any future air-to-air battle between roughly equal opponents is counter-measures. This became an issue half a century ago, as the United States introduced the first effective air-to-air missile; the heat seeking Sidewinder (AIM-9). This simple missile eclipsed the earlier concept for air-to-air guided missiles, best exemplified by the Sidewinder's contemporary, the radar guided AIM-7 Sparrow. Eventually, Sparrow was replaced by a seemingly much more effective AIM-120 AMRAAM. Meanwhile, Russia developed apparently inferior copies of the AIM-9, AIM-7 and AMRAAM.

A few years ago, China introduced the PL-12 air-to-air radar guided missile. U.S. Air Force lobbyists claimed that the PL-12 was superior to the similar American AMRAAM missile, and that Chinese Su-30 fighters carrying the PL-12 would be superior to the current top-dog combination of American F-15Cs carrying AMRAAM. The air force claims that only the faster, stealthier F-22, carrying AMRAAM, can clear the skies of Chinese Su-30s armed with PL-12s. All that depends on how good the two missiles actually are, and how effective each sides countermeasures are.

AMRAAM entered service in 1992, more than 30 years after the first radar guided air-to-air missile (the AIM-7) entered service. Vietnam provided ample evidence that AIM-7 wasn't really ready for prime time. Too many things could go wrong. Several versions later, the AIM-7 got another combat test during the 1991 Gulf War. While 88 AIM 7s were launched, only 28 percent scored a hit. The AIM 9 Sidewinder did worse, with 97 fired and only 12.6 percent making contact. That said, most of these hits could not have been obtained with cannon, especially when the AIM 7 was used against a target that was trying to get away. AMRAAM was designed to fix all the reliability and ease-of-use problems that cursed the AIM-7. But AMRAAM has only had a few opportunities to be used in combat, although 77 percent of the 13 launched have hit something.

The Chinese PL-12 is based on the Russian AA-12, which is regarded as the Russian attempt to produce a missile equal to AMRAAM. The AA-12 is similar in size and weight, weighing 385 pounds (versus 335 for AMRAAM) , 11.9 feet long (12 feet), 200mm in diameter (178mm). The AA-12 has a max range of 90 kilometers (compared to 70 for AMRAAM). The AA-12 has yet to be used in combat. Russian missiles, historically, have been less reliable and effective than their Western counterparts. The Russian missiles are not worthless, they are just less likely to knock down aircraft they are aimed at. The Chinese obviously see flaws in the AA-12 and want to improve that design so that it is more competitive with AMRAAM. The Chinese are eager to create an effective competitor for AMRAAM that they can export (they are already offering the export version of the, the SB-10, for sale.) The PL-12 has, so far, not demonstrated an extraordinary abilities.

But it takes more than a reasonably reliable clone of AMRAAM to threaten sixty years of U.S. Air Force air superiority. As the United States discovered during World War II, pilot quality and tactics were more important than spiffy hardware. The greatest danger to American air superiority is an opponent who spends a lot of effort, and money, on pilot training. China is showing signs of moving in that direction, but is a long way from getting there.

Pilot quality aside, there is the issue of countermeasures. Some of these are involved with pilot training and capability. Countermeasures are much more effective when used by a more capable pilot. But countermeasures are mostly about technology. This ranges from sensors that will detect incoming missiles, to electronic devices that will deceive the rapidly approaching missiles. How countermeasures work is kept secret, more so than how the missiles themselves operate. Both the Chinese and the American missiles and countermeasures work differently, sometimes only slightly. If either side finds out more about how the others missiles and countermeasures, they can tweak their own missiles to be more lethal, and their aircraft to be less vulnerable. China has been making vigorous efforts to obtain U.S. military secrets, with some success. Exactly how much success won't known until there is a war. So when U.S. warplanes go up against their Chinese counterparts with radar guided missiles, all will be revealed. If it's a short war, there won't be much time to make changes. A longer war will be different, and the greater technological and industrial resources of the United States will prevail. But a short war, over the defense of Taiwan against a Chinese invasion, is more likely. This keeps a lot of U.S. Air Force generals awake at night.
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Re: International Aerospace Discussion

Post by Rahul M »

Drevin wrote:Boeing flies first manned aircraft powered by hydrogen. Boeing also recommends electrical power for all auxillary power requirements aboard passenger jets. Just google it up if you want proof.
details please.
as usual the americans claim something already done by others.

soviet hydrogen powered tu-154, named tu-155 flew in 1988.
http://www.flightglobal.com/blogs/fligh ... v-tu1.html

renukb, strategypage has zero credibility. please don't post whole articles from it.
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Re: International Aerospace Discussion

Post by Drevin »

Rahul M
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Re: International Aerospace Discussion

Post by Rahul M »

thanks.
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Re: International Aerospace Discussion

Post by KiranM »

Rahul M wrote: details please.
as usual the americans claim something already done by others.

soviet hydrogen powered tu-154, named tu-155 flew in 1988.
http://www.flightglobal.com/blogs/fligh ... v-tu1.html

renukb, strategypage has zero credibility. please don't post whole articles from it.
Rahul, other than the 'Hydogen' tag we need to draw distinction between them. Tu-155 used hydogen as direct combustible fuel in a jet engine while the Boeing plane used Hydrogen to power a fuel cell which in turn powered a propeller plane.
While the Boeing plane is not the first plane to be powered by Hydrogen it is the first plane to be powered by a fuel cell, the fuel being Hydrogen. (Unless i missed out something else)
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Re: International Aerospace Discussion

Post by Rahul M »

very true. with betterment of technology fuel cell would probably hold the key.
however, I didn't have benefit of the article and drevin's comments didn't mention fuel cell . :)
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Re: International Aerospace Discussion

Post by Arya Sumantra »

Are these guys just finding alternative application for a reactor miniaturized for a submarine in an airplane?

http://www.timesonline.co.uk/tol/news/e ... 024190.ece

October 27, 2008

Nuclear-powered passenger aircraft 'to transport millions' says expert
Call for big research programme to help aviation industry convert from fossil fuels to nuclear energy

Nuclear-powered aircraft may sound like a concept from Thunderbirds, but they will be transporting millions of passengers around the world later this century, the leader of a Government-funded project to reduce environmental damage from aviation believes.

The consolation of sitting a few yards from a nuclear reactor will be non-stop flights from London to Australia or New Zealand, because the aircraft will no longer need to land to refuel. The flights will also produce no carbon emissions and therefore make no contribution to global warming.

Ian Poll, Professor of Aerospace Engineering at Cranfield university, and head of technology for the Government-funded Omega project, is calling for a big research programme to help the aviation industry convert from fossil fuels to nuclear energy.

In a lecture at the Royal Aeronautical Society tonight, Professor Poll will say that experiments conducted during the Cold War have already demonstrated that there are no insurmountable obstacles to developing a nuclear-powered aircraft.

The United States and the Soviet Union both began developing nuclear-powered bombers in the 1950s. The idea was that these bombers would remain airborne, within striking distance of their targets, for very long periods.

The United States tested a nuclear-powered jet engine on the ground and also carried out flight tests with a nuclear reactor on board a B-36 jet with a lead-lined cockpit over West Texas and Southern New Mexico. The reactor “ran hot” during the flights but the engines were powered by kerosene. The purpose of the flights was to prove that the crew could be safely shielded from the reactor.

Each flight was accompanied by an aircraft packed with marines ready to respond to a crash by parachuting down and securing the area.

The test programmes were abandoned in the early 1960s when the superpowers decided that intercontinental ballistic missiles made nuclear-powered planes redundant.

In an interview with The Times, Professor Poll said: “We need to be looking for a solution to aviation emissions which will allow flying to continue in perpetuity with zero impact on the environment.

“We need a design which is not kerosene-powered, and I think nuclear-powered aeroplanes are the answer beyond 2050. The idea was proved 50 years ago, but I accept it would take about 30 years to persuade the public of the need to fly on them.”

Professor Poll said the big challenge would be to demonstrate that passengers and crew could be safely shielded from the reactors.

“It's done on nuclear submarines and could be achieved on aircraft by locating the reactors with the engines out on the wings,” he said.

“The risk of reactors cracking open in a crash could be reduced by jettisoning them before impact and bringing them down with parachutes.”

He said that, in the worst-case scenario, if the armour plating around the reactor was pierced there would be a risk of radioactive contamination over a few square miles.

“If we want to continue to enjoy the benefits of air travel without hindrance from environmental concerns, we need to explore nuclear power. If aviation remains wedded to fossil fuels, it will run into serious trouble,” he said.

“Unfortunately, nuclear power has been demonised but it has the potential to be very beneficial to mankind.”

Professor Poll said an alternative to carrying nuclear reactors on aircraft would be to develop aircraft fuelled by hydrogen extracted from sea water by nuclear power stations.

However, he said that while hydrogen could be suitable for ground-based transport, its energy density was much lower than kerosene and it would be very difficult to design a long-range passenger aircraft capable of carrying enough of the fuel.

Rob Coppinger, technical editor of Flight International magazine, said it was more likely that nuclear reactors would be installed on unmanned air vehicles, used for reconnaissance or in combat, because there would be less need for heavy shielding than on a passenger plane.
Professor Poll will also present research tonight into measures to improve the efficiency over the next decade of short-haul aircraft such as the Boeing 737 and the Airbus A320. He will say that the replacements for these aircraft are likely to fly more slowly, adding about 10 minutes to a typical flight within Europe.

They are also likely to have open-rotor engines, which would use 20 per cent less fuel but could be much noisier than existing jet engines.
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Re: International Aerospace Discussion

Post by renukb »

Boeing sees China buying 3,710 new planes by 2028
Link here
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Re: International Aerospace Discussion

Post by Gerard »

Venezuela joins space club nations
Despite the money spent on the satellite project, Mr Marcano Gonzalez believes the investment is justified, and he cites the example of India.

"Thirty years ago India began its space programme when the country had high levels of poverty. Space technology has allowed the nation to maintain social and cultural cohesion to emerge from under-development.

"Today it is a big power with a voice among nations."
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Re: International Aerospace Discussion

Post by neerajb »

Iraq's AWAAC

Iraq modified four Il-76 into AWAAC type aircrafts namely Bhagdad-1, Bhagdad-2, Adnan-1 and Adnan-2.
Source : Wikipedia

Pics:
http://www.airliners.net/photo/Iran---A ... height=704

http://www.airliners.net/photo/Iran---A ... id=1345698

http://www.airliners.net/photo/Iran---A ... height=676

Does anyone has more info about these aircrafts?

Cheers....
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Re: International Aerospace Discussion

Post by andy B »

neerajbhandari wrote:Iraq's AWAAC

Iraq modified four Il-76 into AWAAC type aircrafts namely Bhagdad-1, Bhagdad-2, Adnan-1 and Adnan-2.
Source : Wikipedia

Pics:
http://www.airliners.net/photo/Iran---A ... height=704

http://www.airliners.net/photo/Iran---A ... id=1345698

http://www.airliners.net/photo/Iran---A ... height=676

Does anyone has more info about these aircrafts?

Cheers....
AFAIK atleast a couple fled to IRAN during the first gulf war where the awacs equipment was removed and they were used as transports i think.
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Re: International Aerospace Discussion

Post by Drevin »

There are two stages in the hydrogen cycle:

stage1:Creating hydrogen (from fossil fuels, biofuels, water etc)
stage2:Using hydrogen with a fuel cell to give water vapour and electrical energy that moves your automobile. zero emissions. no greenhouse gases.

Hence we can see that if hydrogen can be stored like gasoline/petrol in liquid form in a fuel tank the above process brings down pollution from automobiles to zero. So massive environmental benefits.

Another point here is that if water was used to generate hydrogen in stage 1. In stage two hydrogen gets converted back to water. so the process isn't lossy.

So the key problems to solve are:
1. generating hydrogen with least amount of energy and
2. storing hydrogen in liquid form efficiently.

Boeing just demonstrated stage 2 from above in April 2008. Probably the hydrogen used was also in liquid form.

Essentially the environmental impact is zero. We'd still have to pay to fill up our fuel tanks with liquid hydrogen whether its a plane or a car or a two-wheeler.

Imagine it'd be great to generate hydrogen completely from biofuels i.e. jatropa plant etc.
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Re: International Aerospace Discussion

Post by Arya Sumantra »

Drevin wrote:Hence we can see that if hydrogen can be stored like gasoline/petrol in liquid form in a fuel tank the above process brings down pollution from automobiles to zero. So massive environmental benefits.
Not just in liquid form in tanks but Hydrogen storage by adsorption of monoatomic hydrogen onto surfaces of porous structures such as activated carbon etc is being considered.
http://pubs.acs.org/cgi-bin/abstract.cg ... 4543m.html

Hydrogen storage tank (USPTO Application #: 20060054022 )
http://www.freshpatents.com/Hydrogen-st ... 054022.php

Adsorbed Hydrogen can be retrieved from the activated carbon etc simply by heating. These are really compact storage solutions considering that an simple activated carbon tablet the size of a penny from neighbourhood pharmacy has a total surface area equal to a football field!!! Instead of filling up a tank, one can simply leave the empty "cartridge" at the filling station and replace it with another "cartridge" with adsorbed hydrogen.
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Re: International Aerospace Discussion

Post by Drevin »

Producing hydrogen from renewable sources of energy
http://en.wikipedia.org/wiki/Hydrogen_Economy

Vegetable oil
A vegetable oil economy would use green plants and sunlight to make oil from water, CO2 and macro and micro-nutrients. Vegetable oil is safer to use and store than gasoline or diesel, as it has a higher flash point. Vegetable oil works in diesel engines if it is heated first, and is easily converted to biodiesel which can directly replace diesel.[54] Transition to vegetable oil based transportation could be gradual and relatively easy. Auto fueling stations might start with one pump for vegetable oil (as some do now for diesel) and add more, as needed. Since CO2 for this projected use is removed from the atmosphere by green plants to make the vegetable oil and then returned to the atmosphere after it is burned in an engine, there is no net increase in carbon dioxide, so this method is carbon neutral. Green plant derived oils are an example of a renewable energy store that is also safe and easy to make, store, and use. There is interest in using algaculture methods to produce vegetable oil from algae. The main drawback of this approach appears to be the inflationary pressure over vegetable food used to produce these oils.
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Re: International Aerospace Discussion

Post by PaulJI »

Drevin wrote:Producing hydrogen from renewable sources of energy
http://en.wikipedia.org/wiki/Hydrogen_Economy

Vegetable oil
A vegetable oil economy would use green plants and sunlight to make oil from water, CO2 and macro and micro-nutrients. ... Green plant derived oils are an example of a renewable energy store that is also safe and easy to make, store, and use. There is interest in using algaculture methods to produce vegetable oil from algae. The main drawback of this approach appears to be the inflationary pressure over vegetable food used to produce these oils.
Also, land use issues. IIRC it's been estimated that for the UK we'd need more land to replace current fuel usage than we actually have. Aquaculture is only a partial solution to that, as it needs shallow, high-productivity waters, & like land, they are valuable for food production.
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Re: International Aerospace Discussion

Post by PaulJI »

Drevin wrote:There are two stages in the hydrogen cycle:

stage1:Creating hydrogen (from fossil fuels, biofuels, water etc)
stage2:Using hydrogen with a fuel cell to give water vapour and electrical energy that moves your automobile. zero emissions. no greenhouse gases.

Hence we can see that if hydrogen can be stored like gasoline/petrol in liquid form in a fuel tank the above process brings down pollution from automobiles to zero.
If the hydrogen is generated from fossil fuels or biofuels, it does not reduce pollution, but increases it, as it's much more efficient to use the fuel directly than put it through an energy-intensive conversion process. What it does is move the pollution, so instead of emissions being along roads, they are concentrated at the production plant.

If hydrogen is generated by splitting water, using clean (e.g. solar) electricity, then it can reduce overall pollution levels.
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Re: International Aerospace Discussion

Post by Gerard »

MHI likely to launch S. Korean satellite
Though it costs about 10 billion yen to launch an H-2A rocket, observers said MHI might have made a bid substantially lower than that figure on the ground that the H-2A is capable of lifting more than one satellite into orbit. MHI has not commented on this matter....
A huge amount of taxpayers' money has been spent on rocket programs. Development expenses for the H-2A alone were more than 150 billion yen.
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Re: International Aerospace Discussion

Post by vavinash »

The Kompsat-3 only weighs 800 kg. Why isn't ISRO bidding for a PSLV launch. PSLV has a better track record than H-2A and costs a fraction at $ 18 mil compared to $ 101.8 mil for H-2A. Even if MHI offers a cut price 80% discount they can't compete with ISRO.
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Re: International Aerospace Discussion

Post by Babui »

The latest AirForces Monthly magazine has an articles on Rafales invited to fly with the USN Teddy Roosevelt carrier. The Rafales went against the Super Hornets in 1x1 and 2x2 air combat training exercices. While the article doesn't say which aircraft came out on top; it does quote USN pilots saying "Rafales are more nimble fighters" and "Super Hornets were not mean't to be dog-fighters". This would seem to suggest that the Super Hornet got creamed.
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Re: International Aerospace Discussion

Post by Drevin »

If the hydrogen is generated from fossil fuels or biofuels, it does not reduce pollution, but increases it, as it's much more efficient to use the fuel directly than put it through an energy-intensive conversion process. What it does is move the pollution, so instead of emissions being along roads, they are concentrated at the production plant.

If hydrogen is generated by splitting water, using clean (e.g. solar) electricity, then it can reduce overall pollution levels.
The issues here are many: First in a production plant emissions can be recycled and used instead of releasing to the atmosphere. You can't do that in public transport. Second the point in using biofuels is that the source is "renewable".

It is estimated that extracting hydrogen from water through electrolysis is not an energy efficient method taking as much energy to create as available in that quantity of hydrogen. Currently only 4% of the hydrogen manufactured per annum in the US is from electrolysis of water. A large percentage is being manufactured from fossil fuels which are non-renewable sources of energy.

One more issue that is coming up is that a hydrogen fuel cell is an energy expensive replacement for an Internal Combustion Engine. probably taking 3 times more energy to manufacture than an Internal Combustion Engine that it replaces. Mass Production and adoption by the public in a large scale should solve some of these issues.
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Re: International Aerospace Discussion

Post by renukb »

Good details of Ka-5x choppers....

Russia to export 10-15 Ka-52 Alligator helicopters annually - designer news
http://www.domain-b.com/aero/mil_avi/mi ... ussia.html
Vladivostok: Russia will very likely be exporting anything between 10-15 Ka-52 Alligator (NATO designation-Hokum B) attack/reconnaissance helicopters annually, according to Kamov design bureau's chief designer Sergei Mikheyev. Production of these helicopters began Wednesday at the Progress aircraft maker, located in Russia's Far East.
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Re: International Aerospace Discussion

Post by Gerard »

Russia to buy pilotless aircraft from Israel over 3 years
Mikhail Musatov quoted General Staff chief Nikolai Makarov as saying: "The General Staff has decided that while we don't have such drones, over the next two to three years, we will buy them from Israel."
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Re: International Aerospace Discussion

Post by SaiK »

If you don't have 1920x1080p resolution, don't click it.
http://www.hulu.com/hd/29274
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Re: International Aerospace Discussion

Post by Austin »

x posting from keypubs

Awesome video of French M51 SLBM launch 8)

M51 SLBM
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Re: International Aerospace Discussion

Post by Gerard »

Nigerian satellite fails in space
A multi-million dollar Nigerian satellite launched in May 2007 has been shut down to prevent it spinning out of control and damaging others in orbit. The Chinese-built NigComSat-1 cost the African oil producer $340m (£228m).
The satellite was limited because the type of frequency it used was disturbed by clouds in the atmosphere, and did not work properly in Nigeria's rainy season or during the Harmattan, when clouds of dust blow down from the Sahara, he said. The satellite also operated on frequencies already allocated to other companies and interfered with other providers' equipment.
On Tuesday, controllers shut the satellite down because it was having problems with its power supply, the government announced.
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Re: International Aerospace Discussion

Post by Gerard »

Austin wrote:Awesome video of French M51 SLBM launch
Quite interesting. The aerospike deploys as the missile clears the water. There appears to be a wall of bubbles being produced from the base of the nose cone.
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Re: International Aerospace Discussion

Post by Singha »

The satellite was limited because the type of frequency it used was disturbed by clouds in the atmosphere, and did not work properly in Nigeria's rainy season or during the Harmattan, when clouds of dust blow down from the Sahara, he said. The satellite also operated on frequencies already allocated to other companies and interfered with other providers' equipment.

amazing degree of incompetence by the chinese on show here. they
sell a costly piece of gear without verifying if it will work in client
env. some of it like using same frequencies is illegal isnt it?
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Re: International Aerospace Discussion

Post by AdityaM »

Singha wrote:The satellite was limited because the type of frequency it used was disturbed by clouds in the atmosphere, and did not work properly in Nigeria's rainy season or during the Harmattan, when clouds of dust blow down from the Sahara, he said. The satellite also operated on frequencies already allocated to other companies and interfered with other providers' equipment.

amazing degree of incompetence by the chinese on show here. they
sell a costly piece of gear without verifying if it will work in client
env. some of it like using same frequencies is illegal isnt it?
Just got me thinking .... Are Sats in operation insured? that too by a third nation insurer (Insurance company belonging to some other country)?
If your sat doesn't work up to your expectation... how nice it would be to call it a failure & get the insurance amount from the insurer....
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Re: International Aerospace Discussion

Post by Gerard »

more on this
Nigerian satellite launched by China loses power
The Nigerian Communication Satellite, or NIGCOMSAT-1, ceased functioning early Tuesday Beijing time, said Geng Kun, the spokeswoman for Great Wall Industry Corp., the company that sent the satellite into orbit atop a Long March 3-B rocket in May 2007. "The solar wing malfunctioned, which led to exhaustion of electric power, then the satellite failed," Geng said.
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Re: International Aerospace Discussion

Post by Austin »

Gerard wrote:Quite interesting. The aerospike deploys as the missile clears the water. There appears to be a wall of bubbles being produced from the base of the nose cone.
Why are aerospike deployed ?

Why do some slbm have it and some dont feel the need to ( i.e Trident , Bulava ) ?

Thanks
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Re: International Aerospace Discussion

Post by ArmenT »

Singha wrote:
The satellite was limited because the type of frequency it used was disturbed by clouds in the atmosphere, and did not work properly in Nigeria's rainy season or during the Harmattan, when clouds of dust blow down from the Sahara, he said. The satellite also operated on frequencies already allocated to other companies and interfered with other providers' equipment.
amazing degree of incompetence by the chinese on show here. they
sell a costly piece of gear without verifying if it will work in client
env. some of it like using same frequencies is illegal isnt it?
Perhaps they're using the same frequency because they were a bit too overzealous with their cloning efforts and copied that bit as well :D.

Similar thing happened with some Chinese cellphones which all had the same IMEI (International Mobile Equipment Identification) numbers. IMEI numbers are supposed to be unique per device, but the Chinese had cloned the circuitry exactly from another phone (the IMEI ID of the clones indicate that the original was a Nokia) and they didn't bother to change it for each phone. Result: One Paki abdul had his phone stolen and reported it to Paktel. They promptly disabled the phone by its IMEI number. Next few hours, a bunch of abduls reported that their phones had mysteriously quit working :D.
Link to story: http://www.asiamedia.ucla.edu/article.a ... ntid=94421
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Re: International Aerospace Discussion

Post by Singha »

indeed those rs500/- pakphones all 1000s of them stopped working.

Austin, dont know about Bulava but Trident sure uses a aerospike topped with a round plate. I am sure Bulava uses it too if the nose
cone is the round SSN bow shape.

http://www.military.cz/usa/navy/weapons ... ent_en.htm

The Trident II (D5) is a three-stage, solid-propellant, inertially guided FBM with a range of more than 4,000 nautical miles (4,600 statute miles). Trident II is more sophisticated than Trident I (C4) with a significantly greater payload capability. All three stages of the Trident II are made of lighter, stronger, stiffer graphite epoxy, whose integrated structure means considerable weight saving. The missile’s range is increased by the aerospike, a telescoping outward extension that reduces frontal drag by about 50 percent. Trident II is launched by the pressure of expanding gas within the launch tube. When the missile attains sufficient distance from the submarine, the first stage motor ignites, the aerospike extends and the boost stage begins. Within about two minutes, after the third stage motor kicks in, the missile is traveling in excess of 20,000 feet (6,096 meters) per second.
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Re: International Aerospace Discussion

Post by Austin »

Thanks Singha , yes even Bulava seems to have a spheroconical nose so I guess at some point of time it might be using aerospike , a 50 % drag reduction is amazing achievement for an aerospike.
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Re: International Aerospace Discussion

Post by Gerard »

Britain's first mission to the Moon to probe mysterious moonquakes
Ministers will give their approval next month to push ahead with the project which will help engineers to build a lunar base which can withstand the force of the moonquakes. The £100 million mission involves putting an unmanned spacecraft into orbit around the Moon before firing a series of probes into the lunar surface.
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Re: International Aerospace Discussion

Post by soutikghosh »

F-35 JSF to become electronic attack aircraft.

F-35 To Become Electronic Attack Aircraft

--------------------------------------------------------------------------------

Quote:
Nov 30, 2008

By David A. Fulghum

After years of debate about the future of tactical, airborne electronic attack for the U.S. Air Force and Marine Corps, it appears the F-35 will become the next-generation, digital warfare aircraft for both services.

The platform most in demand in combat today is some kind of electronic attack (EA) aircraft, say military operational experts. So the pressure for more aircraft and advanced capabilities is already an operational reality. But the basic question of who does what for whom and to whom remains unanswered.

"Who will provide electronic fires to ground troops in contact?" mused Air Force Maj. Gen. Charles Davis, program executive officer for the F-35 Lightning II. "That's a core mission area for the Air Force, Navy and Marines. Delivering electronic fires will be at the heart of what F-35 does. [But] the decision about how this [and other EA aircraft will be used in the electronic fires arena has not been made."

Despite the vagaries, Davis says, "There is no doubt in my mind that eventually this airplane will fulfill the [EA] role of the EA-6B Prowler."

But development of a specialized electronic attack variant will not take the classic approach that produced the Air Force's EF-111 Raven or the Navy's EA-6B Prowler and EA-18G Growler.

While there's still nothing in the order book, top joint program officials say studies are underway that would add advanced electronic weaponry to the aircraft through the use of exterior pods and antenna arrays. Those add-ons are being designed in parallel efforts such as the Next-Generation Jammer program, and they are aimed at taking advantage of the F-35's inherent connectivity and enhancing the EA capabilities already tucked into the aircraft's interior.

"[The F-35 has] to be interoperable with 80 different platforms and trade 140+ different kinds of information from the ground, ships and aircraft," Davis says. The role of EA aircraft would add at least one more capability to its 23 missions.

Davis hinted at the compatibility of electronic emissions and stealth. "The F-35 is specifically designed to take advantage of lessons learned from [the first stealthy strike aircraft,] the F-117," he says. "Unlike the F-117, the ability to share tactically important information is built into the F-35 [without compromising its] stealth."

But the aerospace industry is not united in the view that the F-35 is the single answer to next-generation, airborne electronic attack. Some specialists worry the F-35 will be short of electrical power and payload space with virtually no room to add systems into its packed interior. The options are to put jammers and additional power supplies in the weapons bays to stay stealthy or put them on the exterior and revert to a stand-off jamming role.

"Every design has its limitations," says a senior electronics industry official with long experience in electronic warfare. "No one aircraft is going to answer all the problems facing airborne electronic attack."

The Growler has two engines, two generators, can produce additional electrical power and could carry the Next Generation Jammer (NGJ), EW specialists note. The NGJ offers a capability for longer-range standoff jamming, is being designed for carriage in a pod with its own ram-air turbine power source and would be available for many platforms.

"I would bet that the EF-35 also will carry the Next Generation Jammer," the EW specialist says. "But if it's in an external pod, [the extra radar reflectivity] will give away the aircraft's location. Yet, if you put the guts of an NGJ into the weapon bays of a single-engine single-generator aircraft in order to maintain all-aspect stealth, you are rapidly going to run out of available power to run it."

There also are questions about designing operational concepts for the F-35.

"If the aircraft has to maintain all-aspect stealth, then how can you do the necessary jamming for a close air support mission or an F-35 strike package from either in close or at standoff range?" the specialist asks.

"And electronic attack is one area where size does matter," he says. "[Despite two false starts,] an EB-52 carrying large-aperture, active electronically scanned array radar with the output of an electronic techniques generator routed through it [such as jamming, false targets, power surges, etc.] can be a very long-range electronic weapon. So, in addition to strike aircraft and bombers, tankers and 737-type aircraft [such as the Navy's E-8 Poseidon, Army and Navy Aerial Common Sensor and Air Force tanker] are also possible platforms for the Next-Generation Jammer. Finally, unmanned aircraft of the Global Hawk and Reaper size could have the necessary size, power and payload."

But will the services get together soon on a common EW/EA plan? The answer is "yes," but they will be reluctant participants because of divergent operational and budgetary needs.

"The budget will be the driver of the solution," the senior electronics industry official says. "They will run out of options before long." And that formula of pressing operational needs and shrinking defense budgets leads back to considering the JSF as a single solution. It is a position which the Marine Corps has already embraced and the Air Force appears to favor.

All three current versions of the Joint Strike Fighter will carry active electronically scanned array (AESA) radars with EW capabilities (primarily self-protection and electronic surveillance) and EA capabilities (the offensive use of false targets, network attack, advanced jamming, algorithm-packed data streams and other techniques) as part of the baseline aircraft delivered to the military.

As designed now, the F-35's combination EW/EA/AESA system allows it to penetrate well-defended targets while suppressing the ability of enemy radars to detect, exchange information about and threaten a mutually supporting group of F-35s.

"We're not bringing in a package that is designed to bring down electronic fires for a widely spread strike force," Davis says. "It's focused on getting a small force of F-35s in and out of a target area with no assistance. It involves anything that would be a threat in suppression or destruction of enemy air defenses missions."

While self-protection, penetration and strike are primary roles for the F-35, it also will have to provide support for the Marines and soldiers on the ground, particularly those in contact with the enemy.

"The F-35's data collection, integration and information sharing capabilities will transform the battlespace of the future and will redefine the close air support mission," Davis contends. But modern close air support will demand the delivery of those electronic fires, on demand for a forward air controller, just as aircraft now deliver bombs, rockets and cannon fire.

To deliver electronic fires as do the EA-6B or EA-18G "would require the addition of [advanced jamming] pods and additional EW arrays," Davis says. Right now, "We are not a wide-area, standoff EW jammer. Our jamming system is designed to get the aircraft into and out of the target area. Can you use it for other things and expand [the EA] capability? Most definitely."

The Marines are now working on delivering electronic fires from EA-6B Prowlers newly modified with the ICAP III EA system that provides jamming, silencing as well as breeching and exploiting enemy communications and signals networks. The Navy has the advanced EA-18G coming into service that will be able to attack an even more sophisticated target set when it upgrades from ICAP III to the still nascent NGJ.

Electronic attack is just one of the advanced missions expected to emerge from the F-35 program. Davis says planners are looking at three notional capabilities associated with unmanned aircraft: sharing data and information with unmanned aerial systems, helping unmanned platforms with targeting and weapons employment and linking a series of UAVs with a series of F-35s to expand attack capabilities.

"There's no doubt you could [field those capabilties] if you chose to," Davis says. "Who controls who, and who offers what data, is what we are looking at."

link: http://www.aviationweek.com/aw/gener...t&channel=awst
Philip
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Re: International Aerospace Discussion

Post by Philip »

Flight Intl. has a good feature on the Pilatus -21 basic trainer,which can replace several training aircraft,including the need for an IJT.The aircraft can be configured to fly like an F-28 or whatever,both cockpits identical and according to the mags test pilot felt like he was flying a jet.The aircraft can also carry munitions and comes in at a major cost saving price,especially as this one single-engined aircraft can replace an IJT and LIFT.

Here's details about an "ultra stealth" bomber project.
http://aviationweek.com/aw/generic/stor ... %20Stealth

Ultra Stealth

May 26, 2008
Bill Sweetman/Minneapolis


NGB demonstrator may be a twin-engine aircraft resembling an X-47B. Initial version will be piloted, but an unmanned endurance version is a probable follow-on.


Is Northrop Grumman building a secret bomber prototype? In late April, the company revealed first-quarter financial results. Data indicated $2 billion in new "restricted programs" contract awards at Integrated Systems, the aircraft division. This almost certainly confirms what DTI first reported earlier this year: Northrop Grumman has a classified, sole-source contract to build a demonstrator for the U.S. Air Force's Next-Generation Bomber (DTI March, p. 30).

USAF budgets show no funding for the Next-Generation Bomber (NGB) itself in 2008, although documents show money for technology work in Fiscal 2008-10. Northrop Grumman CEO Ron Sugar said last year that Integrated Systems had made strides in black programs and identified restricted projects as the top new-business opportunity. Taken together, the evidence points to a single, very large contract win. Northrop Grumman also acquired Scaled Composites in 2007, a company that can develop large prototype aircraft quickly.

The $2-billion contract casts new light on the decision in January by Boeing and Lockheed Martin to reveal their year-old collaboration on NGB. (Boeing, Lockheed Martin and Northrop Grumman declined interview requests.) Hailed as an NGB "dream team" combining Boeing's bomber experience with Lockheed Martin's stealth technology, the teaming now looks like an effort to catch up with a rival that has a lead in the next major U.S. combat aircraft program.

It is likely that the prototype will build on technology under development for the Navy's X-47B Unmanned Combat Air System Demonstrator (UCAS-D), putting within reach USAF's goal of a 2018 initial operational capability date for the bomber. Industry and USAF sources have talked about a competition in 2010, leading to the start of systems development and demonstration in 2011. But it would be Northrop Grumman's to lose.

Events since 2000 placed Northrop Grumman in pole position. USAF interest in a replacement bomber was rekindled after 9/11, but USAF Secretary Jim Roche and Chief of Staff Gen. John Jumper focused on the Lockheed Martin FB-22, seeing it as a low-risk solution that bolstered the case for the embattled F-22.

The departures of Roche and Jumper in 2005 coincided with a change in thinking. In October, USAF defined a three-stage Next-Generation Long-Range Strike program. Phase I would keep the force effective until 2018, with upgrades to aircraft. Phase II would be a new "2018 bomber," while Phase III encompassed hypersonic concepts. This was the end of the road for the FB-22, since nobody envisioned the F-22 remaining in production long enough to dovetail with Phase II.

Late in 2005, at a conference on unmanned combat air vehicles in London, there were signs of convergence between the bomber requirement and the Joint UCAS project. J-UCAS had been kicked off as a major effort three years earlier, but USAF was interested in a platform larger than the Navy could accommodate.

Northrop Grumman J-UCAS Program Manager Scott Winship said at the time that the company had proposed completing a third prototype as an X-47C with a 172-ft. wingspan and 10,000-lb. payload. J-UCAS leader Mike Francis stressed an advantage of the unmanned vehicle: an inherently lower radar cross-section (RCS) than conventional tailed aircraft.

Despite the tension in J-UCAS, it was a surprise when an early-2006 high-level Pentagon review killed it, splitting resources into a white-world Navy effort and a classified USAF program, while endorsing a plan to field a bomber in 2018.

It's now apparent, however, that USAF had already picked a primary approach to the NGB, and that the next two years of work, starting with the remaining Fiscal 2006 J-UCAS funding, are intended to validate that choice.

This approach emerged from J-UCAS, and particularly from Northrop Grumman, which anticipated the J-UCAS split and was prepared to respond. The company believed that the basic 42,000-lb. J-UCAS was better suited to the Navy than to USAF, had focused on the carrier-based J-UCAS demonstration and picked a design that offered high lift and a simple wingfold.

Northrop Grumman's proposal for a bigger X-47C also preceded -- and may have inspired -- USAF's switch to a larger long-range bomber. This meant, too, that the NGB program could get a running start because it would use aerodynamics and stealth technology that were in the works for J-UCAS.

The X-47B was much more advanced, in aerodynamic terms, than it appeared (see sidebar), and the same is likely true of its low-observable (LO) qualities. The aircraft is one of the first to combine a highly blended tailless configuration with new materials developed since the 1980s. The NGB will be the same, if not more so.

Northrop Grumman has stressed the "all-aspect, broadband" stealth inherent in the X-47B. Tailless shapes don't have the "bow-tie" RCS pattern, with the smallest RCS on the nose and tail and peaks on the beam configurations, which characterizes conventional aircraft. They are stealthier against low-frequency radars -- including updated, active-array VHF radars marketed by Russia -- because they do not have shape features which are so small that their RCS in the VHF band is determined by size, rather than shape or materials. It may be significant that John Cashen, leader of the B-2 signatures team, returned in 2006 after 10 years in Australia and is now a consultant for Northrop Grumman.

RCS test facilities across the U.S. have been upgraded since the F-22 and B-2 were designed: USAF's range at Holloman AFB, N.M., was reequipped to handle bistatic measurements, and a sophisticated airborne RCS measurement program based on a modified 737 was delivered in 2001.

How low can LO go? One paper, co-authored by a principal in DenMar Inc., the company founded by Stealth pioneer Denys Overholser, refers to the development of fasteners for a body with an RCS of -70 dB./sq. meter -- one-thousandth of the -40 dB. associated with the JSF, and one-tenth that of a mosquito. DTI queried RCS engineers who don't believe such numbers are possible; but then, when mention of a -30 dB. signature leaked out in a 1981 Northrop paper, nobody believed that either.

Concept Image: Jozef Galtial for DTI
Philip
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Posts: 21538
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Re: International Aerospace Discussion

Post by Philip »

Good feature on the Alligator attack helo here.Members who saw the very first air show at B'lore had the luck to see and touch the two Russian helos,BlackShark and Alligator on display.

http://www.zinio.com/express3?issue=324068337
Shreeman
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Re: International Aerospace Discussion

Post by Shreeman »

What's up with the following?

http://www.abpic.co.uk/photo/1070313/
Gerard
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Re: International Aerospace Discussion

Post by Gerard »

USAF SBIRS photo of a Delta-II rocket launch

http://www.af.mil/shared/media/photodb/ ... 9F-101.jpg
Locked