LCH and other Helicopters Discussion Thread

Singha · Post by **Singha** » 29 Jul 2010 21:11

I recall the MAD magazine series Spy vs Spy

Indranil · Post by **Indranil** » 29 Jul 2010 23:04

andy B wrote:
Singha wrote:a better top speed could be useful in escaping from fighters and aam armed gunships...as also improving the odds against AA fire/manpad shooters.
saar agree that the top speed would be imp in matters that you have mentioned above but given the areas where we will see the LCH deployed I wonder how much of role top speed will play as against ability to carry a decent payload at altitude and being able to manouvere and target potential threats...?

With higher top speeds you can also reach the arena faster.

Kartik · Post by **Kartik** » 29 Jul 2010 23:41

tsarkar wrote:Pratik, I suggest you cross check. If correct, it would be the fastest opening of the flight envelope in aviation history and you broke the stunning news first! The LCH team could look down and frown upon the LCA team who are taking ages to fully open its flight envelope.

there is a huge difference between the two. the LCH also benefited from the fact that its essentially a Dhruv with systems laid out slightly differently to be able to accomodate them inside hte much slimmer fuselage..the engine, transmission, gearbox, blades, etc. are all the same, so its not like its a completely new helicopter.

Rahul M · Post by **Rahul M** » 30 Jul 2010 00:04

chetak wrote:
smpratik wrote:
I have a source working on the project, he says that it went above 300kmph once or twice atleast.

smpratik ji,

And I suppose you think that I spoke to the chowkidar?

depends on if chowkidar is above or below paanwala.

tsarkar · Post by **tsarkar** » 30 Jul 2010 16:55

Kartik, you missed the sarcasm. While reusing engine and transmission does make life easier, flight characteristics and aerodynamics are completely new, and LCH will require exhaustive testing. The news defies belief that a new helicopter, not yet production standard, will be pushed to its limits just months after its first flight.

AFAIK, even the WSI Dhruv is undergoing qualification testing at Nasik and production hasn’t started yet, despite orders being placed.

prastor · Post by **prastor** » 30 Jul 2010 16:58

I think most people are missing the point of the very existence of the LCH. We need a gunship that is specialized in mountain warfare (like another Kargil conflict). The most important factor, that most other choppers miserably failed at, was reliability at extreme altitudes and thin air. In this scenario, LCH knocks the competition out. I mean, it has the highest service ceiling of all gunships in the world, while maintaining an exceptional combat radius. Add the light weight to it which helps immensely in flying at very high altitudes (thin air). All the other stuff like speed are of comparatively lower priority.

Bala Vignesh · Post by **Bala Vignesh** » 30 Jul 2010 18:09

Pastorji, its not reliability that other choppers failed in, its the payload carrying ability... And if i dare say so, everyone here understands the reason why we require a chopper like the LCH...

prastor · Post by **prastor** » 30 Jul 2010 18:18

Bala Vignesh wrote:Pastorji, its not reliability that other choppers failed in, its the payload carrying ability... And if i dare say so, everyone here understands the reason why we require a chopper like the LCH...

Bala Vignesh garu,

I was responding to the extensive debate over the importance of top speed for the LCH that has been going on prior to my posting.

And sorry about the wrong choice of words in saying "reliability" when I actually meant something on the lines as you have mentioned... payload (and even maneuverability?)

Yagnasri · Post by **Yagnasri** » 30 Jul 2010 21:49

Do we have any assembly line of helicapters as of now ?

chetak · Post by **chetak** » 30 Jul 2010 22:31

tsarkar wrote:Kartik, you missed the sarcasm. While reusing engine and transmission does make life easier, flight characteristics and aerodynamics are completely new, and LCH will require exhaustive testing. The news defies belief that a new helicopter, not yet production standard, will be pushed to its limits just months after its first flight.

AFAIK, even the WSI Dhruv is undergoing qualification testing at Nasik and production hasn’t started yet, despite orders being placed.

IMVVHO, many foolish things are being done in the LCH project that go against flight safety.

Adequate and cautious testing is what will bring the project to efficient fruition in the least amount of time.

Showboating for public presentation for antony and other "dignitaries" reveals a management agenda that has something else on it's mind.

It would do well to bear in mind that after all, this is a prototype that we are talking about and not treat it so casually as to go the saras way.

chetak · Post by **chetak** » 30 Jul 2010 22:42

prastor wrote:
Bala Vignesh garu,

I was responding to the extensive debate over the importance of top speed for the LCH that has been going on prior to my posting.

The LCH may well do something around 300 kmph. It will get there in due course. There is no tearing hurry to freak out on this one single parameter in isolation to all others.

There are vital parameters to test and evaluate prior to just stepping on the gas.

BTW, 300 kmph is not enough to outrun even the most basic of missiles.

chetak · Post by **chetak** » 30 Jul 2010 22:44

Narayana Rao wrote:Do we have any assembly line of helicapters as of now ?

There is the assembly line for the ALH which fell woefully short of it's production target last year.

Kartik · Post by **Kartik** » 30 Jul 2010 23:27

tsarkar wrote:Kartik, you missed the sarcasm. While reusing engine and transmission does make life easier, flight characteristics and aerodynamics are completely new, and LCH will require exhaustive testing. The news defies belief that a new helicopter, not yet production standard, will be pushed to its limits just months after its first flight.

AFAIK, even the WSI Dhruv is undergoing qualification testing at Nasik and production hasn’t started yet, despite orders being placed.

where do the aerodynamics of the ALH and LCH differ ? in the airframe and stub wings, that's all. they'll do flutter testing, vibration testing, envelope expansion and if no problems are seen, they'll continue to expand the envelope. However, its not as complicated as a fighter design, not by far. The most important aspects of the helicopter design are the engine, gearbox, transmission and blades, and since they're nearly the same as the Dhruv, there will be few unknowns. the drag will be lower than a regular Dhruv and that would've been validated in a few flights itself. That would mean that even with all similar subsystems and major components, the LCH can be pushed to its max speed in a few test flight blocks.

BTW, I am aware from personal experience of even civilian prototypes being pushed to the limits deliberately and in some cases inadvertently by test pilots. For instance I was shocked to find that a huge airliner prototype nearly went close to Mach 1 in a dive where the TPs did not intend to go, that too within the very first block of test flights. It is certainly not unheard of, especially in newer variants where many subsystems are common with a validated design.

heck, a Rafale went supersonic on its first flight itself. a testament to its great design but also to the test pilot's confidence in it.

Bala Vignesh · Post by **Bala Vignesh** » 31 Jul 2010 13:03

chetak wrote:
BTW, 300 kmph is not enough to outrun even the most basic of missiles.

True sir, but a chopper flying at that speed makes targeting tough in mountainous terrains where the targeting wndow would be small for MANPADS... Unless of course one is already alert about the helicopter...

Avinandan · Post by **Avinandan** » 31 Jul 2010 14:44

SagarP wrote: Especially when people are talking about "whisper modes" and Blue Edge rotor blades.

Eurocopter Moves One Step Closer to ‘Whisper Mode’

Newbie Questions:--
How difficult is to design LCH rotors based upon Blue Edge Rotor Tech ?
How essential is low acoustic signature for an attack helicopter ?

Singha · Post by **Singha** » 31 Jul 2010 14:51

at night and special counter-terror missions it would help.

shiv · Post by **shiv** » 31 Jul 2010 19:00

Avinandan wrote:
SagarP wrote: Especially when people are talking about "whisper modes" and Blue Edge rotor blades.

Eurocopter Moves One Step Closer to ‘Whisper Mode’
Newbie Questions:--
How difficult is to design LCH rotors based upon Blue Edge Rotor Tech ?
How essential is low acoustic signature for an attack helicopter ?

Thanks for pointing this out. I am not going to answer the question - but i want to make a general point because this is one of hundreds of news items of new tech that I have read over the decades.

The industries and economies of Europe and the US survive on such innovations. They come up with new stuff that is required for the market and they sell it.

My point here is not to say that "Blue Edge" is bad or unnecessary - but I want to get a message across about the way Europe and the US lead and make others want to follow them. When they lead and we follow, we are necessarily behind. They sell 2000 helos to 45 countries. We copy and "save foreign exchange" and by the time we think of selling that to others - nobody is interested, and the US/Europe will come up with some better innovation that we then will want to catch up with. We end up producing 57 helos for IAF and 2 for Maldives (free gift) and 1 for Ghana

I think the first thing India needs to decide is whether we are forever going to copy and try and catch up, or whether we decide to develop something on our own and stick with it till we have it right even of the tech is outdated compared with the West. To and extent the Chinese did just that.

In the case of Blue Edge the video refers to urban noise that people in the West, full of helos (police, fire serice, media, private) keep hearing. Technically that noiseless helo would be useless for large parts of Africa. We need to develop something inexpensive and reliable that we can sell to a host of African and other developing nations (and to our own police forces) even if the rotor tech is standard noisy tech. Only then will we begin to achieve some sort of leadership in the world that others might want to emulate.

Sorry to go off on a tangent - but like I said - i have spent too many decades watching Indians wanting to catch up, and never catching up and never even managing to do something 100% at home even if it is lower tech - because we are always criticising ourselves for being low tech and outdated and always playing catch up. That is how we export nothing while even Pakistan exports the K 8, abd China is still merrily exporting MiG 21 level tech.

chetak · Post by **chetak** » 31 Jul 2010 20:49

Rahul M ji,

You have mail.

Suresh S · Post by **Suresh S** » 31 Jul 2010 21:50

Hi Shiv,

With a background similar to yours I myself have reached very similar conclusions over the years .
Indians must find indian solutions to indian problems even though not always reinventing the wheel.
Use your brains and do something that you feel right about and pursue it even though others may laugh at you initially.Now that requires self belief and confidence. A phoren education and exposure and struggle every day to beat the white man at his game and facing difficulties everyday and seeing yourself doing better than them can give you that confidence and self belief even though I think it is by no means a must. I think you can do this right in India without ever having to leave.

More later

skn

disha · Post by **disha** » 31 Jul 2010 21:54

Avinandan wrote:
SagarP wrote: Especially when people are talking about "whisper modes" and Blue Edge rotor blades.

Eurocopter Moves One Step Closer to ‘Whisper Mode’
Newbie Questions:--
How difficult is to design LCH rotors based upon Blue Edge Rotor Tech ?
How essential is low acoustic signature for an attack helicopter ?

There is something called innovation and then there is innovation in marketing. One thing we need to understand is that the world cannot ever beat US in marketing. At least not in this generation. In this particular case the innovation means nothing for India. We still have to give our first version of locally designed and manufactured copters in vast numbers, be it civilian or millitary. Once the first version is given out in vast numbers, then constant incremental innovation will keep in contention. Once in a while a small leap will leap frog it ahead of its contemprories.

This model in mind is the Toyota. Initially, Japaneese cars were laughed at. Small cars, small engines etc. With ever small increments and tight quality, currently they are considered world class.

Added later: Rest of the west generally follows US in marketing. They are just a step behind.

disha · Post by **disha** » 31 Jul 2010 22:03

snahata wrote:Use your brains and do something that you feel right about and pursue it even though others may laugh at you initially.Now that requires self belief and confidence. ... can give you that confidence and self belief even though I think it is by no means a must. I think you can do this right in India without ever having to leave.

Leaving the shores will give the uber-under-confident desi something to measure against and boost her/his self-esteem. That exposure is must. Indians by general are extremely under-confident and hence they tend to dismiss/diminish themselves.

One of the issue for us is that we should but do not have is loads of Not-Invented-Here (NIH) syndrome. That is, if it is not invented in India, then it must be bad. Once as a general population we get there, the rest will follow. Of course this may lead to some re-inventing wheel but that is a smaller problem.

For LCH, since it is Indian designed with Indian inputs, it is definitely good for India. It may not be good for US or UK but who cares. As long as we can manufacture some 1000s of this helos in various mark I and mark X avatars and also find countries with similiar problems and even gift them (Angola, Namibia, Vietnam, Kenya, Ugandam, Peru, Chile) in various avatars like reconnisense, patrolling, anti-poaching it will serve its purpose.

Rahul M · Post by **Rahul M** » 01 Aug 2010 04:01

chetak ji, received and replied.
thanks.

Victor · Post by **Victor** » 01 Aug 2010 07:06

Kartik wrote:.. its essentially a Dhruv with systems laid out slightly differently to be able to accomodate them inside hte much slimmer fuselage..the engine, transmission, gearbox, blades, etc. are all the same, so its not like its a completely new helicopter.

There is still too much "Dhruv" in the LCH and I believe the current model is only a proof of concept. It will probably undergo further surgery in the next upgrades to reduce weight and provide optimal design for an attack chopper while retaining the critical Dhruv components and systems. For example, note the huge tail wheel that is needed to help it's "cargo belly" clear the deck. With a slight re-orientation of the rotor axis, it could take on a much slimmer profile.

Hopefully, the focus will be firmly on producing a "good enough" attack chopper that we can induct in quantity as soon as possible without getting bogged down in details like "stealth" etc. Those can come in incremental improvements later.

shiv · Post by **shiv** » 01 Aug 2010 08:41

It just occurred to me - I have heard the ALH Dhruv, the Mi 8/17 and Aluoette III/Chetak hundreds of times. Of these three - only the Dhruv goes "whirrrrrrr". The others go "thak-thak-thak-thak". Check YouTube for confirmation.

ShivaS · Post by **ShivaS** » 01 Aug 2010 21:39

Blade design and cavitation?

Anujan · Post by **Anujan** » 01 Aug 2010 22:41

It is a well known effect called "blade slap"

Some angles of flying (like banking etc) cause the vortices generated by the main rotor to be "slapped" by the tail rotor. This causes noise at different flying conditions for different helos.

Ofcourse, a lesser "thak thak" noise is created by the blade tips slapping on the vortices generated by the previous blade. The loudness/frequency of this noise depends on the harmonics of the speed of the rotation of the main rotor (slower rotations producing deeper noise and faster rotations producing high pitched noise)

nachiket · Post by **nachiket** » 01 Aug 2010 22:45

^^Could the number of blades also make a difference? The Dhruv and LCH have 4 compared to the 2 on the Alouette II and III.

Venkarl · Post by **Venkarl** » 01 Aug 2010 22:58

shiv wrote:It just occurred to me - I have heard the ALH Dhruv, the Mi 8/17 and Aluoette III/Chetak hundreds of times. Of these three - only the Dhruv goes "whirrrrrrr". The others go "thak-thak-thak-thak". Check YouTube for confirmation.

Shiv..my ears are bad at....can you tell me about LCH? does it sound similar to ALH or shakti's improvement made it any difference?

Telang · Post by **Telang** » 02 Aug 2010 02:57

I hope none missed the comparison table at:
http://forums.bharat-rakshak.com/viewto ... &start=720

Atleast there is one thing in the LCH that makes it "numero uno", among the combat Helis. LCH has the top service ceiling of all!!

We must not jump and celebrate just yet. The capabilities may be the projected ones and not the achieved ones! At the same time we need not be dishearted either, because there will be lot more improvements before the serial production starts.

nachiket · Post by **nachiket** » 02 Aug 2010 03:17

Whatever specs we have of the LCH are the design specs. The real specs will be obtained after the flight envelope is fully opened during testing.

shiv · Post by **shiv** » 02 Aug 2010 08:21

Venkarl wrote:
Shiv..my ears are bad at....can you tell me about LCH? does it sound similar to ALH or shakti's improvement made it any difference?

I haven't heard the LCH often enough or even concentrated on the sound to be able to comment - but I will keep my ears open. I believe the rotor is the same as in Dhruv so I doubt if it will sound different considering that it is rotor noise and not engine or body generated noise.

Kailash · Post by **Kailash** » 02 Aug 2010 11:50

deleted.

Singha · Post by **Singha** » 02 Aug 2010 15:06

does the wing loading and wing area fundae used in fighters apply to rotary wings? i,e, a heli with greater rotor area (more blades or broad blades) would be less lightly loaded and hence more agile? gunship helis seem to vary from 2 blade (ah1) to 4 (ah64)

Lalmohan · Post by **Lalmohan** » 02 Aug 2010 16:41

blade mass and drag are probably more significant factors...

Venkarl · Post by **Venkarl** » 03 Aug 2010 03:43

shiv wrote: I believe the rotor is the same as in Dhruv so I doubt if it will sound different considering that it is rotor noise and not engine or body generated noise.

I am so noobie..Thanks Shiv

Avinandan · Post by **Avinandan** » 03 Aug 2010 17:21

Marten wrote:Will the second prototype perhaps include a ducted fan tail rotor or a Notar design to reduce noise?
Saw the MD500 two years ago (learned neighbor pointed it out the obvious lack of a tail rotor). Looked awesome but somewhat incomplete. Would be nice to see some innovation in the design aimed at making it more TFTA/sales-worthy.

I really doubt if ducted fan tail rotor or NOTAR would be implemented for LCH. If it was so great, then all of the attack helicopters would have incorporated it by now(exception:Comanche). Moreover before trying it with LCH, we would have tested it with ALH Dhruv first. However Ducted fan tail rotor do have lots of advantages over the regular one, not sure why it has not been incorporated by now.. probably because of weight considerations...

putnanja · Post by **putnanja** » 04 Aug 2010 19:51

From Shiv Aroor's blog http://livefist.blogspot.com . Click on image for higher res image.

ALH Dhruv Cockpit: Old & New

Chinmayanand · Post by **Chinmayanand** » 06 Aug 2010 02:01

'Homemade' chopper 90 per cent imported, reveals CAG

The myth surrounding the much-hyped advanced light helicopter (ALH) Dhruv, touted as an indigenously-built showpiece, has been laid to rest. The Comptroller and Auditor General (CAG) has revealed that 90 per cent of material used in it was imported. The Rs 2,103-crore project should have been at least 50 per cent indigenous.

What's more, the 74 helicopters supplied to the armed forces fall short of expectations. Planned as a replacement for the Cheetah/Chetak fleet of the army and air force, the 5.5-tonne ALH has been found unsuitable due to its excess weight and underpowered engines.

Plans to equip it with the more powerful Shakti engines are behind schedule. The CAG said the engine was yet to be certified.

The armed forces had frozen their technical requirements more than three decades ago.

Limited series production kicked off in 2001. But non-freezing of the ALH design by Hindustan Aeronautics Limited (HAL), according to the auditor, led to 363 modifications.

The HAL has orders for 159 ALHs from the army and air force. The navy, which has six of the helicopters, has found its anti-submarine warfare capabilities to be inadequate and is looking for a replacement.

"In the absence of a clear understanding between the navy and the company (HAL), the Rs 138 crore spent on the project has not resulted in any benefit to the customer," the CAG report, tabled in Parliament on Thursday, said.

Craig Alpert · Post by **Craig Alpert** » 06 Aug 2010 03:58

OFFICIAL CAG REPORT ON DHRUV

Code: Select all

Year 	Envisaged produc-tion plan 	Available capacity 	Orders on hand as per delivery schedule 	Cumul-ative orders on hand 	Orders on hand as per delivery schedule 	Production targets BE RE 	Actual produ-ction 	Cumul-ative actual produc-tion 	Back log in product-ion (5)-(9) 	 
(1) 	(2) 	(3) 	(4) 	(5) 	(6) 	(7) 	(8) 	(9) 	(10) 	(11) 	 
1997-98 to 2000-01 	48	 -	-	-	-	-	-	-		-	 
2001-02 	24 	12 	8 	8 	8 	8 	7 	7 	7 	-1 	 
2002-03 	32 	12 	3 	11 	3 	10 	11 	11 	18 	+7 	 
2003-04 	32 	24 	18 	29 	18 	18 	13 	13 	31 	+2 	 
2004-05 	32 	24 	14 	43 	14 	18 	18 	14 	45 	+2 	 
2005-06 	32 	24 	25 	68 	25 	20 	18 	18 	63 	-5 	 
2006-07 	32 	24 	10 	78 	10 	24 	15 	14 	77 	-1 	 
2007-08 	32 	24 	1 	79 	1 	24 	4 	4 	81 	+2 	 
2008-09 	32 	24 	31 	110 	31 	24 	18 	15 	96 	-14 	 
Total upto 31 March 2009 	296 	--	110 		110 	146 	104 	96 		20* 	 
Future orders 2009-10 to 2015-16 			139 (defence)3 + 6 (from others) 		139 (defence)4 + 6 (from others)

The Company has so far (December 2009) delivered 90 ALH, out of which 74 ALH were delivered to defence customers and 16 ALH to other customers. The Company has orders on hand for 159 ALH from defence customers and 6 ALH from other customers to be delivered by 2015-16. The weaponised version of ALH is still under development.

Problems in ALH - Anti Resonance vibration Isolation System, Control saturation, Weight of ALH, Integrated Architecture Display System,Shakti engines, Delay in development of Weapon System Integration (WSI) versions, Certification for ALH

Hal response to CAG for Control Saturation:

The Management stated (April 2009 and December 2009) that the complete rework of design during prototype stage was not carried out as the collaborator did not consider it necessary from the safety point of view. Control saturation is not a design deficiency but is a phenomenon that can occur during extreme manoeuvres. The precautionary notes and adequate cautions are part of the flight manual. It is in the process of incorporating control saturation warning system. The Company further accepted that the necessity for increased control margin has been discussed with Air Force and it was decided that considering the predominantly Nap of Earth (NOE) flying of light combat helicopter (LCH), it is necessary to incorporate increased right control margin on LCH. The Company’s reply leaves a doubt about the effective measures it has taken on the control saturation issue and the reaction of the customers will be known only on the field experience of the ALH to be supplied from the pending orders.

gogna · Post by **gogna** » 06 Aug 2010 04:40

Chinmayanand wrote:'Homemade' chopper 90 per cent imported, reveals CAG

The myth surrounding the much-hyped advanced light helicopter (ALH) Dhruv, touted as an indigenously-built showpiece, has been laid to rest. The Comptroller and Auditor General (CAG) has revealed that 90 per cent of material used in it was imported. The Rs 2,103-crore project should have been at least 50 per cent indigenous.

What's more, the 74 helicopters supplied to the armed forces fall short of expectations. Planned as a replacement for the Cheetah/Chetak fleet of the army and air force, the 5.5-tonne ALH has been found unsuitable due to its excess weight and underpowered engines.

Plans to equip it with the more powerful Shakti engines are behind schedule. The CAG said the engine was yet to be certified.

The armed forces had frozen their technical requirements more than three decades ago.

Limited series production kicked off in 2001. But non-freezing of the ALH design by Hindustan Aeronautics Limited (HAL), according to the auditor, led to 363 modifications.

The HAL has orders for 159 ALHs from the army and air force. The navy, which has six of the helicopters, has found its anti-submarine warfare capabilities to be inadequate and is looking for a replacement.

"In the absence of a clear understanding between the navy and the company (HAL), the Rs 138 crore spent on the project has not resulted in any benefit to the customer," the CAG report, tabled in Parliament on Thursday, said.

10% are the screwdrivers which are used to put it all together. LCH is even worse