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PostPosted: 03 May 2012 20:34 
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Hari Nair wrote:
The LCH - climbing above 6000 m - a view in the cockpit


If that is not a warning to those jokers who might be planning a rehash of kargil...... I dunno what is.

Hold your horses losers ... its on its way


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PostPosted: 03 May 2012 20:55 
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Location: General Error : Bhery Phamous General !
great shot !!


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PostPosted: 03 May 2012 21:07 
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@Shiv - The shot was whilst climbing beyond 6000m - and as you said - it is rather impressive!
@Rahul - Thanks!


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PostPosted: 03 May 2012 21:30 
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sorry guys

where are the pics??


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PostPosted: 03 May 2012 22:01 
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Hari Nair wrote:
The LCH - climbing above 6000 m - a view in the cockpit
http://img39.imageshack.us/img39/7520/lchclimbingoutof6000m1.jpg


Sir, any insights on the fire-power mix carried by LCH at such extreme heights ?? :wink:
Btw, an awesome shot, sir! :D


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PostPosted: 03 May 2012 22:09 
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thanks krishg

strange I cannot see the link in Hari's post


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PostPosted: 03 May 2012 22:16 
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Nice! 6000 meters is awesome. Would we be able to do the same in a fully loaded lch ?


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PostPosted: 09 May 2012 04:08 
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At 20,000 ft> AGL or pressure altitude, depending on outside air temperature, icing is a probable variable that the LCH design team will have to consider, for sustained operations.


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PostPosted: 09 May 2012 08:20 
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Aksai Chin is 5000 meters.


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PostPosted: 09 May 2012 08:41 
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Rahul M wrote:
good job picklu. get a good lens for pujo instead of the customary shirts. ;)


the term "lyad" indicates Piklu is a bong just like me..!!


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PostPosted: 09 May 2012 09:10 
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Cybaru wrote:
Nice! 6000 meters is awesome. Would we be able to do the same in a fully loaded lch ?



Interestingly WikiBaba lists the service ceiling of "The Beast" at 6500m. I am sure it would not be possible to take it to 6000m "Fully Loaded", but should be able to reach there with a "useful" combat load.

hnair...you rock \m/


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PostPosted: 09 May 2012 09:30 
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Bala Vignesh wrote:
First off, Thanks a load for sharing the pics of the LCH and ALH.. Its good to see the program progress..
Hari Nair wrote:
Well, there are quite a few changes in the offing - some of which will be pretty visible soon - we will be posting the pics - when we manage to get some good ones.
The project milestones - we will definitely talk about those when we meet up!

This does it.. Time for the next BR Meet in Bangalore.. Its been a year since the last meet in any case.. Rahulda any chance you'll be dropping by???


Sorry bangalore gurus I am no longer live in Bangalore to host it. Last time it was fun. Let me know when you are hosting. Will come to meet you all. By the way I am in TN now if there is any meet in Chennai I can travel and attend.


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PostPosted: 09 May 2012 10:55 
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shiv wrote:
Aksai Chin is 5000 meters.

What about the rest of the Tibetan plateau


The Himalayan-Tibetan orogen was created by the Indo-Asian collision over the past 70-50 Ma. Significant crustal shortening (at least 1400 km) which leads to eventual construction of the Cenozoic Tibet Plateau, began more or less synchronously in the Eocene (50-40 Ma) (figure 1). The orogen, which is the youngest and most spectacular active continent collisional belt on Earth, has long been known as the golden key to the global orogenic mechanism, and the natural laboratory for continental dynamics theory.
Tibet is the largest, highest and flattest plateau in Earth with an average elevation exceeding 5000 m. It is bound by the deserts of the Tarim and Qaidam Basins to the north, the Himalayan, Karakoram, and Pamir mountain chains to its south and west but its eastern margin is more diffuse (figure 2). The Tibetan plateau was uplifted more than 4 km and the crust under the central part of it has thickened up to 70 km (double the thickness of most continental crust). Although several models have tried to explain how such topography formed, we still have much to learn.


Last edited by svinayak on 09 May 2012 10:58, edited 1 time in total.

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PostPosted: 09 May 2012 10:58 
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10,000ft is claimed as the avg height of tibet plateau...same as Ladakh plain areas like Leh.


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PostPosted: 10 May 2012 05:05 
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Image

Tiger HAD testing... Maybe future variants of LCH Could incorporate some of the features present uptop! Wishful thinking, but depending on how much weight is shredded in the current LCH, it is very doable!


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PostPosted: 10 May 2012 06:37 
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Craig Alpert wrote:
http://media.defenseindustrydaily.com/images/AIR_Tiger-HAD_w_Spikes_Mistrals_Runway_lg.jpg

Tiger HAD testing... Maybe future variants of LCH Could incorporate some of the features present uptop! Wishful thinking, but depending on how much weight is shredded in the current LCH, it is very doable!


Well I can see a hideous orange thing sitting right in front of the front cockpit blinding the chap there and humongous ugly tourist windows, no electro optical sensor and a radar that can only see front and sides and a stupid looking floppy used condom like thing hanging off the gun. I hope none of those is going to get incorporated. Wiki says the service ceiling is 4000 meters. Enough to go and crash into the side of a Himalayan mountain :roll:


Last edited by shiv on 10 May 2012 06:38, edited 1 time in total.

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PostPosted: 10 May 2012 06:38 
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shiv wrote:
[Re: Tiger-HAD] Wiki says the service ceiling is 4000 meters. Enough to go and crash into the side of a Himalayan mountain :roll:
:rotfl:

This is great! I actually laughed out loud.


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PostPosted: 10 May 2012 07:09 
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shiv wrote:
Craig Alpert wrote:
http://media.defenseindustrydaily.com/images/AIR_Tiger-HAD_w_Spikes_Mistrals_Runway_lg.jpg

Tiger HAD testing... Maybe future variants of LCH Could incorporate some of the features present uptop! Wishful thinking, but depending on how much weight is shredded in the current LCH, it is very doable!


Well I can see a hideous orange thing sitting right in front of the front cockpit blinding the chap there and humongous ugly tourist windows, no electro optical sensor and a radar that can only see front and sides and a stupid looking floppy used condom like thing hanging off the gun. I hope none of those is going to get incorporated. Wiki says the service ceiling is 4000 meters. Enough to go and crash into the side of a Himalayan mountain :roll:


Those orange things are cameras for testing. And that 'condom' is some ground crew being lazy with his jacket. However, it goes without saying that I love our LCH much more :-)


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PostPosted: 10 May 2012 07:34 
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shiv wrote:
Well I can see a hideous orange thing sitting right in front of the front cockpit blinding the chap there and humongous ugly tourist windows, no electro optical sensor and a radar that can only see front and sides and a stupid looking floppy used condom like thing hanging off the gun. I hope none of those is going to get incorporated. Wiki says the service ceiling is 4000 meters. Enough to go and crash into the side of a Himalayan mountain :roll:


:rotfl: Nice of shiv to do a SDRE style self-flagellation on behalf of the Europeans.


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PostPosted: 10 May 2012 08:50 
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shiv wrote:

Well I can see a hideous orange thing sitting right in front of the front cockpit blinding the chap there


Unless I missed your sarcasm, You do realize that "hideous orange thing" is a Test equipment correct :roll: It doesn't come as part of a standardize package!

shiv wrote:
a radar that can only see front and sides

Again, Unless I missed your sarcasm, atleast Tiger has a Radar!


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PostPosted: 10 May 2012 09:00 
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Craig Alpert wrote:
shiv wrote:

Well I can see a hideous orange thing sitting right in front of the front cockpit blinding the chap there


Unless I missed your sarcasm, You do realize that "hideous orange thing" is a Test equipment correct :roll: It doesn't come as part of a standardize package!

shiv wrote:
a radar that can only see front and sides

Again, Unless I missed your sarcasm, atleast Tiger has a Radar!


Well you wished for a whole lot of Tiger things on the LCH. I was talking about what i did not want to see. There is a lot about the Tiger that i do not want to see on the LCH. I worry that you might be wishing for all the drawbacks including the worthless service ceiling.

Did you really want a radar that is half blind because it is embedded in the body because they could not solve the mast vibration issues that the Apache designers have solved? How about no radar rather than half radar? But I admit the radar will detect the mountain before hitting it.

Sarcasm? Take it that way if you want. I could be serious.


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PostPosted: 10 May 2012 11:50 
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In any case, that isn't a radar, it's the optronic sighting system. It faces towards the rear in the 'rest' position.

Bliss to see

So no, tiger doesn't have a radar yet.


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PostPosted: 10 May 2012 12:51 
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What is interesting is the position of the sensor..... definitely clarifies the doubt that the over the nose sensor in LCH causes no 'blind spot'


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PostPosted: 10 May 2012 15:19 
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SidSom wrote:
What is interesting is the position of the sensor..... definitely clarifies the doubt that the over the nose sensor in LCH causes no 'blind spot'


Sorry saar, perhaps you missed it - why was the doubt any less clarified when Hari Nair said it? Do we have to get proof from Eurocopter?


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PostPosted: 10 May 2012 15:34 
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Shiv saar,
That line about the radar detecting the mountain before crashing had me rolling..
About the things that tiger has that i wish for LCH is the funding.. Nothing more..


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PostPosted: 10 May 2012 15:38 
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Hari Nair Sir,
Thanks for sharing such an awesome pic.. A round of whatever you have when, if ever, we meet..


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PostPosted: 10 May 2012 19:25 
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shiv wrote:
Well you wished for a whole lot of Tiger things on the LCH.

Okay let's not start with selective reading first. I had said "some" not a "whole lot" big difference! The features that I was reffering to were passive weapons sys such as CM's & Radars & rotor blade noise suppressors.
shiv wrote:
I was talking about what i did not want to see. There is a lot about the Tiger that i do not want to see on the LCH. I worry that you might be wishing for all the drawbacks including the worthless service ceiling.

Negative! I don't want those drawbacks on LCH. LCH is built around Indian Requirements and Operating ceiling in mind. I'm in content with you on this.

shiv wrote:
Did you really want a radar that is half blind because it is embedded in the body because they could not solve the mast vibration issues that the Apache designers have solved? How about no radar rather than half radar? But I admit the radar will detect the mountain before hitting it. .


My career in the service has taught me one thing, something is better than nothing! A radar with limitations is still better than flying with no radar depending on your mission profile!


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PostPosted: 10 May 2012 19:30 
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as long as the helo is 100% stealth and passive scanning mode, burst moded radar is all that we need. I don't think we have super skirosky type stealths in our plans.


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PostPosted: 10 May 2012 20:35 
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Craig Alpert wrote:
My career in the service has taught me one thing, something is better than nothing! A radar with limitations is still better than flying with no radar depending on your mission profile!

Absolutely sir. A helo with limitations should similarly be better than no helo at all.

Both LCH and the Tiger have their limitations. What was it about the Tiger you wanted to see on the LCH? You did not specify.

I have a reason for doing this. To be very frank your post looked to me like a fanboy post of a genre which instantly compares anything Indian with something from abroad merely to point out what is better and desirable in the non Indian one. I did exactly the opposite like an Indian fanboy because someone has to play that role too.


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PostPosted: 10 May 2012 20:57 
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shiv wrote:
Craig Alpert wrote:
http://media.defenseindustrydaily.com/images/AIR_Tiger-HAD_w_Spikes_Mistrals_Runway_lg.jpg

Tiger HAD testing... Maybe future variants of LCH Could incorporate some of the features present uptop! Wishful thinking, but depending on how much weight is shredded in the current LCH, it is very doable!


Well I can see a hideous orange thing sitting right in front of the front cockpit blinding the chap there and humongous ugly tourist windows, no electro optical sensor and a radar that can only see front and sides and a stupid looking floppy used condom like thing hanging off the gun. I hope none of those is going to get incorporated. Wiki says the service ceiling is 4000 meters. Enough to go and crash into the side of a Himalayan mountain :roll:


:-? :-? :-?


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PostPosted: 10 May 2012 22:38 
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shiv wrote:
SidSom wrote:
What is interesting is the position of the sensor..... definitely clarifies the doubt that the over the nose sensor in LCH causes no 'blind spot'


Sorry saar, perhaps you missed it - why was the doubt any less clarified when Hari Nair said it? Do we have to get proof from Eurocopter?


To rephrase.....Looking at the optical sensor near the rotor I got the doubt that this was a bad place for the sensor. Then remembered HNair sirs clarification that at alts and ranges it would be used at it would not make a diff if it was above the nose or in this case near the rotor.


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PostPosted: 10 May 2012 23:28 
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shiv wrote:
Both LCH and the Tiger have their limitations. What was it about the Tiger you wanted to see on the LCH? You did not specify.

Correct, I did not specify that in my original post. Incase you missed it in the previous post, The features that I was referring to were passive weapons sys such as Counter Measures & Radars & rotor blade noise suppressors.

shiv wrote:
To be very frank your post looked to me like a fanboy post of a genre which instantly compares anything Indian with something from abroad merely to point out what is better and desirable in the non Indian one. I did exactly the opposite like an Indian fanboy because someone has to play that role too.

:roll: Really? Wow, I'm at loss of words for this one chief! I don't know how "looking into" having additional capability for future variants/further maturity and growth of LCH meant a "fanboy post." Infact, it is the opposite and shows the maturity in a platform, where one can explore additional mission profiles on such a system.
In terms of what is better, let's face it we all know where HAL stands as oppose to its counterparts however, "desirable in the non-Indian one" - Absolutely! Why not? What's wrong with wishful thinking? Haven't you ever wondered of exploiting a system to its full potential or perhaps potentials that you were unaware of that it can achieve? A little more R&D into this would only benefit HAL and give it fair chance to play a bigger part in the IAF & possibly earn it a seat at the big boy table. Just my 2 cents!
Rest assured, I’m not a fanboy of any systems - I've seen enough to know that technology leap plays a significant part in giving you an upper hand over your adversary; however I've seen firsthand that wars are won with strategies and equipments on hand.


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PostPosted: 11 May 2012 06:34 
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Craig Alpert wrote:
In terms of what is better, let's face it we all know where HAL stands as oppose to its counterparts however, "desirable in the non-Indian one" - Absolutely! Why not? What's wrong with wishful thinking?

So your less than complimentary views of HAL are being painted on to the LCH. And because HAL stands in a particular place as compared to its counterparts (which you refuse to commit) the Tiger needs to be copied? I know you did not say this originally, but the posting of a huge photo of the Tiger with the cryptic message: "Tiger HAD testing... Maybe future variants of LCH Could incorporate some of the features present uptop! Wishful thinking, but depending on how much weight is shredded in the current LCH, it is very doable!" suggests that you were able to see some fantastic features in the Tiger that I was unable to see.

And now you say that your feelings are related to your views on "where HAL stands"? I may have been spot on in my reading of the sense of your post.

Craig Alpert wrote:
Haven't you ever wondered of exploiting a system to its full potential or perhaps potentials that you were unaware of that it can achieve?


However I am fully aware of where the LCH scores over the Tiger. You failed to specify what you saw as worthy of copying and you cannot expect everyone to be aware of what you have in your mind. I specified what it is about the Tiger that must not be copied. And for that you are giving me a lesson about HAL's pedigree and your deep personal insight into technology?

Craig Alpert wrote:
Rest assured, I’m not a fanboy of any systems - I've seen enough to know that technology leap plays a significant part in giving you an upper hand over your adversary; however I've seen firsthand that wars are won with strategies and equipments on hand.


Lets get this straight. I am an out and out LCH fanboy. I am not claiming that it's the best in the world, but neither am I going around passing dark hints about its less than pedigree antecedents at HAL and making suggestions of how "we all" know where HAL stands as opposed to its counterparts. Your views about pedigree and antecedents are confirmation about your attitude to me, which is something that I read instantly when I saw that Tiger post of yours. It is also a lesson that I will use in future to diss or praise something based on its perceived pedigree.


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PostPosted: 11 May 2012 10:14 
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the pic of the tigre in previous page does indeed reveal the blade tip noise suppressor design developed by eurocopter. older pics of tigre dont show it. its like the end of the rotor instead of being sharp cut, is shaped like a boomerang with a trailing knife edge.

http://static.flickr.com/3041/2724840316_a4715779d1.jpg

the optronic ball in the nose sounds like a better position to me - less obstructed by the fuselage for engaging near targets. the apache longbow layout sounds like the best available. optronics in nose and radar atop the mast...abd big CFT type cheek fairings for avionics and fuel bays, plus a place for SF troopers to stand on in shack and awe kamandu pics


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PostPosted: 11 May 2012 15:39 
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There is now a fair amount of information about rotors and noise, but less info about rotor noise versus efficiency (fuel efficiency/lift/altitude capability etc) . Every link I find suggests that noise reduction features tend to reduce aerodynamic efficiency. Also there is very little information about whether noise reduction is achieved at all power settings, heights and speeds or whether there is a narrow band of speed/power/altitude where noise reduction is maximal.

Precious little information is available other than a large number of technical papers detailing causes of noise and noise modeling and prediction. In the meantine Eurocopterhas gone apeshit talking about its "Blue edge" rotor blade tips but there is not a chirp about fuel and lift efficiency gains or losses. One thing is sure. If there was a gain in efficiency, they would have announced it and tomtommed it from the highest minarets.

Slobbering after photos of helos with noise reduction rotor tips sounds more fanboyish to me than any serious technical commentary and this is something that probably requires a little attention and study on the forum.

Helicopter noise is a big deal in European and American cities. Dropping supplies or supporting troops or casevac at over 5000 meters is not an issue for either the Europeans or Americans unless they are looking to sell helos to India, China, Pakistan or Chile. And if it was, guess where the testing would have to be done?


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PostPosted: 11 May 2012 17:26 
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If you can observe carefully the tigre's rotor(the root section mainly) is very very very similar to the ALH/LCH rotor and it uses the same lead-lag damper that the ALH/LCH used previously. The tip is different though and am not sure how much of a difference that makes(maybe hari sir can elaborate if he finds it fit). I was even told of cases where eurocopter (erstwhile MBB) guys would seek our root end section test data(most crucial test for a rigid rotor) by one of our HOD's but not comment on the data AT ALL.(i have a story on the general indian sense of inferiority despite being almost world-class which i will try and post in the relevant thread )


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PostPosted: 11 May 2012 19:49 
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even the basic Dhruv is pretty quiet...a quiet humming vs the metallic clanking of the Mi17 enough to wake up anyone.


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PostPosted: 12 May 2012 21:26 
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Have we considered the BERP blade for the LCH?

http://terpconnect.umd.edu/~leishman/Aero/berp.html

ENAE 632 --The British Experimental Rotor Program (BERP) Blade
What is the BERP blade?

"The BERP blade was the result of ten-years (1976-1986) of aerodynamic research collaboration between Westland Helicopters and the Royal Aircraft Establishment.
This research paid off on 11th. August 1986 when the Westland company demonstrator Lynx (G-LYNX) attained the world absolute speed record for any helicopter, which remains in place more than ten years later. The Lynx achieved an average speed over a 15km course of 249.1 mph (400.87 kph), which broke the previous record of 228mph (367 kph). This high speed could not have been achieved without the use of the BERP blade.
The confidence that has since been established with the BERP blade means that this technology is now being applied to other helicopters. For example, the BERP blade will be standard equipment on the Lynx III battlefield helicopter and the new EH-101, the latter which is being developed jointly by Westland and Agusta. "

Quote:
How does it work?

If we wish to reduce compressibility effects in forward flight, we can use sweep on the tip of a rotor blade. Many modern helicopters use some form of simple sweepback on the blade tip. Examples are the UH-60 Blackhawk and the AH-64 Apache.
However, so we don't get center of gravity or aerodynamic center movements aft of the blade elastic axis (which can introduce undesirable aerodynamic and inertial couplings), then the tip must be configured with an area shift forward. This can be kept to a minimum by recognizing that the Mach number is varying along the blade so we do not have to use a constant sweep angle, thereby minimizing the amount of forward area shift.
The methodology used in the design of the BERP blade ensures that the effective Mach number normal to the blade remains nominally constant over the swept region. The maximum sweep employed on the large part of the BERP blade is 30 degrees and the tip starts at a non-dimensional radius r/R=cos 30 = 86% radius. The area distribution of this tip region is configured to ensure that the mean tip center of pressure is located on the elastic axis of the blade. This is done by offsetting the location of the local 1/4-chord axis forward at 86% radius.
This offset also produces a diskontinuity in the leading edge (referred to as a notch), which results in other interesting effects. For example, recent calculations using a CFD code based on the Navier-Stokes equations, has shown that this "notch" actually helps to further reduce the strength of shock waves on the blade. Thus, an unexpected by-product of the notch over and above the basic effect of sweep is to help to reduce compressibility effects even further.
We must also recognize that a swept tip geometry of this sort will not necessarily improve the performance of the blade at high angles of attack corresponding to the retreating side of the disk. In fact, experience has shown that a swept tip blade can have an inferior stalling characteristic compared to the standard blade tip.
The BERP blade employs a final geometry that performs as a swept tip at high Mach numbers and low angles of attack, yet also enables the tip to operate at very high angles of attack without stalling. This latter attribute was obtained by radically increasing the sweep of the outermost part of the tip (the outer 2% approximately) to a value (70 degrees) where any significant angle of attack will cause leading edge flow separation.
Because the leading edge is so highly swept, this leading edge separation develops into a stable vortex structure which rolls around the leading edge and eventually sits over the upper surface (as on a delta wing aircraft). This mechanism is enhanced by making the leading edge of the airfoil in this region relatively sharp.
As the angle of attack is increased, then this vortex begins to develop from a point further and further forward along the leading edge, following the planform geometry into the more moderately swept region. At a sufficiently high angle of attack, the vortex will initiate close to the forward most part of the leading edge near the "notch" region.
Evidence has shown that a strong "notch" vortex is also formed, which is trailed streamwise across the blade. This vortex acts like an aerodynamic fence and retards the flow separation region from encroaching into the tip region. Further increases in angle of attack make little change to the flow structure until a very high angle of attack is reached (in the vicinity of 22 degrees!) when the flow will grossly separate. For a conventional tip planform, a similar gross flow breakdown would be expected to occur at about 12 degrees local angle of attack.
Therefore, the BERP blade manages to make the best of both worlds by reducing compressibility effects on the advancing blade and delaying the onset of retreating blade stall. The net result is a significant increase in the operational flight envelope.


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PostPosted: 16 May 2012 12:51 
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I think I saw the LCH flying back to it's nest just a while ago! Can anybody confirm?!


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PostPosted: 18 May 2012 03:02 
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Still no "burping"?


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