Combat Aircraft technology and Evolution

[Bahamut]

It's you who did not read the article well.

"xxx These nozzles further mask the engine hot parts while flattening the exhaust plume and generating vortices. xxx"

A flat exhaust plume spreads the exhaust heat in the atmosphere in a much wider space thus dissipating the heat resulting in cooler exhaust plume than in jets with concentrated (rounded) exhaust plumes.

But as I mentioned earlier, this IR signature reduction scheme makes significant difference on long ranges. On short ranges, it does not make much difference.

Interestingly, from F117, to B-2, to F-22 the exhaust plumes are flattened by flat exhaust nozzles or exits. The F-35 break the mold. This is one reason why observers conclude that at least on the aft section the F-35 is not as stealthy as F-22. But most conclude this is done to reduce cost since the conventional rounded nozzle in F-35 is much cheaper to construct than the more complicated exhausts of previous stealth planes.

It is on the tenth line of the article you posted

These nozzles further mask the engine hot parts while flattening the exhaust plume and generating vortices.

A flat exhaust plume spreads the exhaust heat in the atmosphere in a much wider space thus dissipating the heat resulting in cooler exhaust plume than in jets with concentrated (rounded) exhaust plumes.

That is due to a different technique (11 line of the article )

Minute holes are evident on their inner surfaces, likely providing bypass air for enhanced cooling.

 

[StealthFlanker]

F-22A flat nozzles are not for IR or RCS reduction

Square nozzle does help reduce IR signature, the Russian did an experiment on the Su-27 with square nozzle and results was very promising.

The trade off is that square nozzle reduce thrust and are much heavier than round nozzle. That why RUS didn't use it on PAK-FA and US changed to serrated nozzle on F-35, which still have IR signature reduction benefits but not as heavy

There are other techniques too such as cooling channels inside the nozzle flaps

 

[asianobserve]

The trade off is that square nozzle reduce thrust and are much heavier than round nozzle. That why RUS didn't use it on PAK-FA and US changed to serrated nozzle on F-35, which still have IR signature reduction benefits but not as heavy

There are other techniques too such as cooling channels inside the nozzle flaps

The higher engine weight in F-22 engine compared to F22 engine is mainly due to TVC. The Americans calculated that TVC is not needed in F-35.

 

[Sam Biswas]

cant agree more
if possible we should add another production line that is the third one,and rectify and upgrade our aircraft as and when required ,this will be far more sustainable
rather than buying foreign fighters now and even after 40 years

Building all defense weapons including fighter jets in India is unquestionably best way to go. But at the same time, "reinventing the wheel" in every stage of development is a stupid approach and financially prohibitive not to mention time-constraint. Indians must think of a balanced approach that will be the correct mix of indigenous and imported technologies. Neither Russia nor France will ever share anything with India and one can state that with confidence from their past dealings with India. If Israel or USA wants to manufacture weapons and fighter jets in India providing Indians with skills and know-how, it will be a sheer wastage of time and money to reinvent those technologies just for meaningless national pride.

One can argue that China and Russia both reinvented all the wheels they have now, then why shouldn't India follow the same path. The answer is that neither of those countries had access to the "wheel" and they had no choice. Now India has free access and should utilize it to the fullest.

 

[no smoking]

One can argue that China and Russia both reinvented all the wheels they have now, then why shouldn't India follow the same path. The answer is that neither of those countries had access to the "wheel" and they had no choice. Now India has free access and should utilize it to the fullest.

No, that is only a reason which is correct for certain period of time.
The real reason is both countries have similar experience of fighting superior enemy ALONE or even once fighting coalition of all the major countries troops. They both learned the lesson with great pain: lacking weapon is worse than shit weapons.
So, the top priority of both of their military industries is: must be able to supply weapons without any foreign aid within years long total war.

 

[airtel]

No, that is only a reason which is correct for certain period of time.
The real reason is both countries have similar experience of fighting superior enemy ALONE or even once fighting coalition of all the major countries troops. They both learned the lesson with great pain: lacking weapon is worse than shit weapons.
So, the top priority of both of their military industries is: must be able to supply weapons without any foreign aid within years long total war.

Stop comparing China with Russia

You are not fight with superpowers with superior technology....... You are just a bully who is harassing his smaller neighbors.

Your last war was with Vietnam and not with any superior country.

And even after much bigger force and large amounts of weapons you lost that war. :biggrin2:

 

[airtel]

Building all defense weapons including fighter jets in India is unquestionably best way to go. But at the same time, "reinventing the wheel" in every stage of development is a stupid approach and financially prohibitive not to mention time-constraint. Indians must think of a balanced approach that will be the correct mix of indigenous and imported technologies. Neither Russia nor France will ever share anything with India and one can state that with confidence from their past dealings with India. If Israel or USA wants to manufacture weapons and fighter jets in India providing Indians with skills and know-how, it will be a sheer wastage of time and money to reinvent those technologies just for meaningless national pride.

One can argue that China and Russia both reinvented all the wheels they have now, then why shouldn't India follow the same path. The answer is that neither of those countries had access to the "wheel" and they had no choice. Now India has free access and should utilize it to the fullest.

Americans will not share their 5th generation technologies with India.

License production is possible but most importantly foreign weapons are extremely costly...... After installing Indian aesa, engine, ew suite tejas will become extremely cheap....and then we wil produce it in large no.

We will get a cheap 4th generation aircraft in large no. which will be able to fire BVR missiles and drop bombs on the target .



We are not reinventing the wheel we are developing new technologies like GaN based AESA radars and EW suites.

 

[Kchontha]

IMHO manufacturing or producing f16 or gripen in India will help India for a short term basis by arresting fighter/squadrons shortage of IAF due to impending retirement of MiGs. But this type of arrangement won't help India in the long run because there is doubt in quantum of technology transferred involved in the deals. For instance American won't transfered F110-GE-132 engine technology used by F 16 block 60 as its power plant. This would be similar to HAL assembling SU30MKI. On the otherhand if the govt invest time and money on LCA MK2 and simultaneously on AMCA then India would be in league with Sweden (SAAB) or China in terms of fighter jet manufacturing capabilities in a decade time. This will benefit in the long run as India will be having both single and double engine world class indigenous fighter jets manufacturing capacities. For that to happen India has to invest heavily on jet engine technology, radar, sensor fusion, stealth technology, ram coating etc etc. Otherwise India will be a helpless technology dumping site for these western countries for the time being.

 

[Kunal Biswas]

Its best you know the basics before posting your comments on quality threads ..

Building all defense weapons including fighter jets in India is unquestionably best way to go. But at the same time, "reinventing the wheel" in every stage of development is a stupid approach and financially prohibitive not to mention time-constraint.

 

[TPFscopes]

. .

 

[gadeshi]

A G5 medium fighter concept from Stavatti Aircraft Company:

 

[gadeshi]

KRET and NIITsE have developped and ready to deliver ECM-augmented towed air decoys and new advanced ECM containers for Vitebsk-25 and Vitebsk-29, Vitebsk-52 ESM/ECM suits for Su-25SM3 and MiG-29K/KUB/SM/SMT/M/M2 and Ka-52/52K respectively:
https://sdelanounas.ru/blogs/98622/

 

[gadeshi]

Space optics technologies comes to aviation - UOMZ optical mechanical plant (OLS-UEM IRST for MiG-29K/KUB/M/M2/35/35D and T-220 land targetting optical pod producers) Director General big interview:
http://take-off.ru/item/3954-kosmic...go-konstruktora-ao-npk-spp-viktorom-sumerinym

 

[asianobserve]

Lockheed to develop experimental laser for fighters

Lockheed Martin has received a $26.3 million contract to develop and produce a laser than can be tested on a fighter jet by 2021.

The initiative will see Lockheed develop a high power fiber laser as part of US Air Force's Research Lab's Self-protect High Energy Laser Demonstrator (SHiELD) programme, says Lockheed in a statement.

ShiED has three subsystems: the beam control system that directs the laser to the target, a pod that powers and cools the laser, and the laser itself.

https://www.flightglobal.com/news/a...velop-experimental-laser-for-fighters-442928/

 

[Tactical Frog]

Airbus unveils new Future Combat Air System ...

 

[asianobserve]

INTERVIEW: Rolls Royce engine expert discusses future fighter technology

Rolls-Royce believes that advanced engines will be the single most important design factor for future fighter aircraft.

Banks believes that the physical characteristics of fighters, whether manned or unmanned, will largely be driven by the shape of the propulsion system – which comprises the engine as well as the intake and exhaust.

This is a departure from the past, where airframers would develop an aircraft, and call on engine-makers to provide an engine of a certain thrust. The change is largely driven by the premium placed on stealth, which demands that engines be buried deep in an aircraft. S-shaped inlets fore and aft ensure that radar waves cannot reach engine parts without bouncing around the intake or exhaust. Shaping, however, while crucial, is not enough: radar absorbent materials (RAM) are also necessary to absorb radar waves.

"By the time you've got these S-shaped intakes front and back, the length of the propulsion system is very long," says Banks. "The airframers want it to be as short as possible because then the aircraft does not have to be unnecessarily large, and they've got more space for weapons and fuel."

A key focus area for R-R is the development of distortion-tolerant military fans, which are better able to deal with separation of air flow issues. Banks says the length of the intake in front of the engine is determined by fan-size. If the length is less than four times the fan diameter, "very, very high distortion levels" occur.

"What you want to do is crumple [the intake] up as much as possible, and do the same with the exhaust," says Banks. "The more you crumple this up, the shorter the length of the propulsion system, and the more flexibility the airframer has to design the aircraft."

Another focus area is an embedded starter-generator that could save space and provide the large amount of electrical power required by future fighters. Banks says power demand on fighters will rise exponentially, with electricity needed for powerful radars, electrically-actuated control surfaces and directed energy weapons.

So R-R is working on fusing magnets to the rotating shaft of the engine, which can reach 15,000 rotations per minute. The placement of wires outside this creates an electric motor. "If you have magnetics rotating, and you have wires, you generate electricity."

"

We can remove all of the gearbox underneath the gas turbine. Now we tell the airframer that all we need is a battery or electrical power source, and that starts your engine for you… it's a win-win. Everything is beneficial."

The company is also continuing to develop advanced composites that can reduce weight inside the engine.

Work is underway on these systems at Rolls-Royce's lab in Bristol. Banks stresses that the technologies are not being developed with a specific aircraft in mind, but for futuristic programmes in general. One of these, of course, is the prospective British-French Future Combat Air System (FCAS).

https://www.flightglobal.com/news/a...-engine-expert-discusses-future-fight-445940/

 

[Adioz]

So R-R is working on fusing magnets to the rotating shaft of the engine, which can reach 15,000 rotations per minute.

They could also use magnetohydrodynamic generators. They can place this in the combustor if possible. Such placement will allow the absorption of energy from the plasma before it enters turbine stages. This will allow a higher combustion temperature without raising the TET (Turbine Entry Temperature).
This can also be used, to a certain extent, to power the sensors on hypersonic weapons.

 

[asianobserve]

This is an old video of Auto-GCAS in actual operation on an F-16 when the pilot passed out during intense maneuvers:

 

[BON PLAN]

A G5 medium fighter concept from Stavatti Aircraft Company:

F23 inspired ....

 

[gadeshi]

F23 inspired ....

Not really, but some nose section resemblance is present