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Indian Military Helicopters

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Vivek K
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Re: Indian Military Helicopters

Postby Vivek K » 02 Oct 2017 23:01

You left out - Mig-23 purchase (nothing stellar about them), Mig-29 and Mig-29k purchase (seems like the money on Ks was flushed down the drain and the earlier smoky 29s had severe teething troubles) and the Mig-27s (still serving).

Also there is the Gorky purchase - not competitive - went over by just a little (about $1.5B over quoted and accepted price) - can the Gorky go further than the Indian ocean without blowing a gut?

There are also the HDW and the Scorpene purchases. The HDW was a good system but corruption/kickbacks killed its future. The Scorpene is a good system but the Frogs sold us out to the land of Oz.

Of course, our beloved Ajeya and Bheeshma (if he had a grave, Bheeshma wold probably come out of it to save Hastinapur from such a system), the T-72 and the T-90 - (not competitive purchases) - need a lot of tank recovery vehicles to move them anywhere.

Defence procurement is an iffy process the world over.

Thankfully our Jawans, Pilots and Sailors make world beaters out of the pathetic purchases that the babus make. And so the Bheeshma becomes a feared, potent weapon in the IA's hands - they could do the same for Arjun (if they wanted to). It is the training and the motivation of the men that wins or loses wars.

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Re: Indian Military Helicopters

Postby Indranil » 03 Oct 2017 01:55

Hakeem,

You ask difficult questions. I will take the bait and say something unsavoury which many may not like.

Competition is a great way to get the best price, or product, or a combination thereof. But to run a competition, the objective and the upper limit of one's ability to pay should be known. Unfortunately, MMRCA should be taught as an example of how not to run a competition.
1. Clear objective? When IAF allowed Gripen-E to F-18 Super hornets, it cannot claim a clear objective. Other than "anything but LCA and Su-30". While it explicitly stated the latter, it did not spell out the former.
2. Upper limit of price? I have two choices to choose from: a) IAF did not know what 126 Rafales/EFs cost, or b) It knew, but it took MoD/MoF for a ride because there is no other way to get 126 Rafales/EF. That number is 4 times what India can pay!
3. Who is in charge? Customer, GoI or supplier. In this case, the supplier took GoI and IAF for a nice ride. And we all obliged. Name one stated objective of MMRCA which was fulfilled by the 36-Rafale buy?

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Re: Indian Military Helicopters

Postby Indranil » 03 Oct 2017 02:10

Coming back to topic, here's what I think about LUH/Ka-226.

1. Philip sir, Modi/Putin signed an MoU to form a JV. That has been formed. The same was done for MTAL.
2. Philip sir, Brahmos JV is the same as the Su-30 MKI JV. ToT is greatly questionable. And it is true for other JVs too e.g. MMR radar or MRSAM. In the latter parts, we at least developed some tech of our own.

3. Ka-226 brings nothing new in terms of capability over the LUH. LUH will beat it at high altitude performance because it is designed for that purpose alone. And the KA-226 is sure to get e step motherly treatment from HAL. Why go there?
4. If LUH's basic flight profile can be cleared by Dec'2017, start serial production. It has very low risk of failing any of the high/hot/cold tests. Other than the transmission, there is hardly anything new from the tried and tested ALH. They already know the tolerances they need to have in the plains to handle the fringes of the envelop at hot, high and cold temperatures.
5. LUH's and Ka-226 will roughly come at the same speed. They have to create a new plant to start the Ka-226 production. LUH's suppliers are the same as ALH. In fact, production can start in the ALH hangars and shift to the new hangars as soon as possible.

Engage Kamov. Between Kamov and HAL, they have everything that is required to come up with a coaxial rotor, pusher-prop heli. That is the future and has readymade customers in IA/IAF/IN who have already shown interest in the same.

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Re: Indian Military Helicopters

Postby srai » 03 Oct 2017 04:23

Indranil wrote:Hakeem,

You ask difficult questions. I will take the bait and say something unsavoury which many may not like.

Competition is a great way to get the best price, or product, or a combination thereof. But to run a competition, the objective and the upper limit of one's ability to pay should be known. MMRCA should be taught as an example of now not to run a competition.
1. Clear objective? When IAF allowed Gripen-E to F-18 Super hornets, it cannot claim a clear objective. Other than anything but LCA and Su-30. While it explicitly said the latter, it did not spell out the former.
2. Upper limit of price? I have two choices to choose from: a) IAF did not know what 126 Rafales/EFs cost, or b) It knew, but it took MoD/MoF for a ride because there is no other way to get 126 Rafales/EF. That number is 4 times what India can pay!
3. Who is in charge? Customer, GoI or supplier. In this case, the supplier took GoI and IAF for a nice ride. And we all obliged. Name one stated objective of MMRCA which was fulfilled by the 36-Rafale buy?

After all that, there is yet another 200* "single-engine" import competition :((

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Re: Indian Military Helicopters

Postby Khalsa » 03 Oct 2017 04:53

^^^^ facepalm

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Re: Indian Military Helicopters

Postby Gagan » 03 Oct 2017 07:29

WRT the MMRCA contest. The merits of the contest apart, the IAF did get a really close dekko at all the 4.5 gen fighters from around the world.
These represented the leading 4.5 gen techs from all the plane manufacturers

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Re: Indian Military Helicopters

Postby mody » 03 Oct 2017 18:32

For Ka-226, we should just execute the first part of the order, i.e. buy 60 outright from Russia, with an option for an additional 30.
LUH can fulfill the balance requirement of 300-350 helicopters.

Kamov and HAL should form a joint venture for replacement of Ka-27/28/31 family of naval helis. We have a requirement of more then 120 of these and I am sure Russia can use a replacement for these over the next 10-15 years as well. All the sensors and weapons should be topnotch, with no water down export version for anti-sub sensors.

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Re: Indian Military Helicopters

Postby Philip » 03 Oct 2017 18:58

The problem is our patchy execution of orders Best seen with LCA production.Admittedly helo unit is doing better but HAL has a massive order Book with ALHs,LCHs,dev. the Med.helo,etc.The new plant for KA-226 will have work for a decade+ and there's nothing to prevent even the LUH from being built there once dev. is complete.Pl remember that the IA needs these helos aeons ago.The Kamov's unique modular ,changeable cabins is a plus point for diff. missions unlike the LUH.

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Re: Indian Military Helicopters

Postby Rakesh » 03 Oct 2017 19:01

srai wrote:After all that, there is yet another 200* "single-engine" import competition :((

Where were you? Your presence was missed in the SE bashing thread. Please come back and Bash On Regardless :)

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Re: Indian Military Helicopters

Postby Indranil » 03 Oct 2017 19:54

Philip wrote:The Kamov's unique modular ,changeable cabins is a plus point for diff. missions unlike the LUH.

The interiors of almost all modern helis can be reconfigured in half an hour or less. The same is true for ALH and LUH.

If having interchangeable pods was such a great idea, how come nobody wants the Ka-226? Or no other manufacturer feels the need to design their future helis that way?

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Re: Indian Military Helicopters

Postby shiv » 03 Oct 2017 20:18

Indranil wrote:
Philip wrote:The Kamov's unique modular ,changeable cabins is a plus point for diff. missions unlike the LUH.

The interiors of almost all modern helis can be reconfigured in half an hour or less. The same is true for ALH and LUH.

If having interchangeable pods was such a great idea, how come nobody wants the Ka-226? Or no other manufacturer feels the need to design their future helis that way?

Indranil - the sentence on top is valid.

Regarding the second assertion, a unique item is always positioned as a niche in a market that offers everything else. For example the Dhruv was positioned as a unique helo in the 5.5 tonne class. What Dhruv does was available in heavier helos (and lighter as well). Market positioning is a trick that sometimes works and sometimes does not. The A 380 is struggling a bit now in a market that was led by the 747 for decades

And you know the US has the Skycrane which was a humongous version of the Ka 226.

The issue of why is no one else copying it is not necessarily because it is useless. Few people copy the twin rotors of CH 47 (only the Brits did) and other than Kamov very few people go for twin main rotors with no tail rotor.

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Re: Indian Military Helicopters

Postby Gagan » 03 Oct 2017 20:53

The thing to remember is that the Ka-226 won in the absence of a flying LUH
If the LUH had been around, one wonders if the competition would really have taken place.
But then Saint Anthony was around, so all bets are off as to the need for such a competition in the first place.

That being said, the Mark 3 Dhruvs are doing just great.
The Ka-226s removable cabin is an interesting tech - If they can carry a pallet in place of that cabin and drop the pallet off at the posts up in siachen that is a useful capability. Its like a mini Sirkorsky Skycrane

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Re: Indian Military Helicopters

Postby shiv » 03 Oct 2017 22:01

They could carry a cabin and drop the entire cabin off with survival equipment

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Re: Indian Military Helicopters

Postby srin » 03 Oct 2017 22:17

tsarkar wrote:
Indranil wrote:I believe these are for the CG. The gun will be mounted on the port side door.

IN & ICG OPV on patrol duties are armed with Chetaks with door mounted MMGs. But I agree with Thakur's POV - the 20 mm stabilised gun developed for Rudra is much better than unstabilized door guns with significantly less ammunition wastage due to much better accuracy and the development work being completed. The longer range of 20 mm keeps the helicopter relatively out of MANPADS & RPG range vis-a-vis door mounted guns. The doors & cabins are free for cargo/troops instead of being cluttered by gunner & ammunition cans. The pilots can operate the 20 mm instead of the excess load of door gunner who is ballast when gun not in use.

Problem is those drafting requirements sometimes just keep the usual way of doing things instead of exploring new possibilities. The other challenge is getting Financial Approval from embedded Defence Accounts folks. The financial approval process is simpler if existing systems/processes like door guns are carried forward instead of "new" nose gun. Anything with past precedence gets approved quickly without a complex justification process.

The only positive part is ships and helicopters getting 12.7 mm HMG instead of older 7.72 mm MMG.


Do we have the equivalent of the minigun (7.62mm gatling gun) in use ?

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Re: Indian Military Helicopters

Postby Gagan » 03 Oct 2017 22:38

shiv wrote:They could carry a cabin and drop the entire cabin off with survival equipment

If someone is having a HAPE etc, they can take a pressurized hyperbaric oxygen chamber right up the glacier, provided DRDO or the Russians build one with Aluminium or Carbon Fibre. Or a small OT / OR right up there.

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Re: Indian Military Helicopters

Postby shiv » 03 Oct 2017 22:50

DRDO has a HAPO bag.Will post image tomorrow

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Re: Indian Military Helicopters

Postby Gagan » 03 Oct 2017 23:03

Image

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Re: Indian Military Helicopters

Postby Gagan » 03 Oct 2017 23:04

Image

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Re: Indian Military Helicopters

Postby Indranil » 04 Oct 2017 00:13

The only thing that interests me is the ability to strip out the cabin altogether.

But the Ka-226T has a higher empty weight than LUH and lower power. So, I am not too sure that Ka-226 will have the same payload as LUH at high altitude.

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Re: Indian Military Helicopters

Postby Gagan » 04 Oct 2017 02:42

Ka 226 is a twin engined chopper vs LUH being a single engined one.
Maybe if they put two shakti engines on it (Given that it will be assembled in India), it'll have better high altitude performance

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Re: Indian Military Helicopters

Postby Indranil » 04 Oct 2017 03:21

^^^ I don't get it.

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Re: Indian Military Helicopters

Postby Gagan » 04 Oct 2017 03:37

You're saying higher empty weight for the Kamov. It is a twin engined helo.
The LUH is a single engined light helo

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Re: Indian Military Helicopters

Postby Indranil » 04 Oct 2017 03:59

The two engines on the 226T put together generate as much power as the one engine on the LUH.

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Re: Indian Military Helicopters

Postby Indranil » 04 Oct 2017 04:10

Raghuk, Can you answer why HAL went from a 2-stage gear box to a 3-stage gear box on the LUH. Lower wear and tear and maintenance?

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Re: Indian Military Helicopters

Postby Rakesh » 04 Oct 2017 04:11

As per wiki chacha, each Turbomeca Arrius 2G1 engine aboard the Ka-226T produces 580 hp each x 2 = 1,160 hp. The Turbomeca Shakti 1U engine produces 1,706 hp. That represents a 32% increase in hp of the LUH over the Ka-226T.

https://en.wikipedia.org/wiki/HAL_Light ... Helicopter

https://en.wikipedia.org/wiki/Kamov_Ka-226

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Re: Indian Military Helicopters

Postby Indranil » 04 Oct 2017 04:40

Those numbers are not correct.

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Re: Indian Military Helicopters

Postby Sid » 04 Oct 2017 05:34

^^ Even if those numbers are right, integration of a European engine with Roosi Heli is no longer possible due to sanctions.

Kamov will deliver first few examples directly from their factories, hence this 220T model may not be viable any longer. Meaning first batch will have Roosi engine, which we will have to retrofit with French engine. And who will pay for that?

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Re: Indian Military Helicopters

Postby shiv » 04 Oct 2017 06:16

Sid wrote:^^ Even if those numbers are right, integration of a European engine with Roosi Heli is no longer possible due to sanctions.

Kamov will deliver first few examples directly from their factories, hence this 220T model may not be viable any longer. Meaning first batch will have Roosi engine, which we will have to retrofit with French engine. And who will pay for that?

Is this guess work like our media or do you have a quote from official source? We keep complaining that media are taking stuff off BRF. How long before this statement becomes "news"?

As an aside - it is one thing to complain that well researched facts from gurus are being copied by the media which causes both pride and indignation. On the other hand we have whole lot of guesswork and speculation - and if that guesswork is going to attract eyeballs surely the media will pick it up. We won't complain if that happens will we, and admit that it was BRF speculation? In fact we will say "Hey BRF is ahead of curve. I said that 2 months ago and now the media are reporting it", BRF is also media and if we curse the media for misinformation and curse them for copying us - we need to make sure that we check our own misinformation.

If we really care that is..Or else it is time pass

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Re: Indian Military Helicopters

Postby srin » 04 Oct 2017 07:09

Gagan wrote:Ka 226 is a twin engined chopper vs LUH being a single engined one.
Maybe if they put two shakti engines on it (Given that it will be assembled in India), it'll have better high altitude performance


If they put two shakti engines on it, it'll be called Dhruv :D

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Re: Indian Military Helicopters

Postby srin » 04 Oct 2017 07:12

Btw, while comparing Ka-226 and LUH, please see Vivek Ahuja's analysis: http://thebetacoefficient.blogspot.in/2015/04/the-indian-light-utility-helicopter.html

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Re: Indian Military Helicopters

Postby Philip » 04 Oct 2017 12:05

The bird was tested against the French filly and won handsomely according to reports ,meeting all IA parameters. Let's let the issue rest there.There is still no LUH in production when the IA has reqd. these aircraft ,waiting for it for at least half a decade.Chetaks crash with reguaalrity.They're probably still flying on goodwill ! Now the market is so huge for small LUH class helos both mil and civil that when Kamov prod. is nearing its end,LUH production will then begin.End-users can evaluate both and choose the one they prefer. In any case the GOI will support the desi LUH as much as it can since the req. will be huge.If we operate around 200MI_17Vs,and a few hundreds of ALHs,then imagine the numbers of LUHs too.Being cheaper,they would be more in demand like Maruti Altos and Kwids.I envisage a req. of at least 300-400+ LUHs by 2030,which means that our production should be at least 2-3 /month.A pvt. hospital in TN has started a flying ambulance helo service ,one lakh a trip,according to media reports. Such services esp. in the NEast /HImalayas are bound to multiply and the tourist industry will cash in with the ability to transport guests to tourist spots where road/rail infrastructure is poor.
It would be interesting to see what an hr.'s flying time for a KA-226/LUH will cost.

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Re: Indian Military Helicopters

Postby JayS » 04 Oct 2017 12:39

Philip wrote: Now the market is so huge for small LUH class helos both mil and civil that when Kamov prod. is nearing its end,LUH production will then begin.


More likely LUH and Ka226 production will start at the same time. Only advantage with Ka-226 is we will get some units in flyaway condition, and even that is questionable as when. The way things go, the argument that such purchases were made to fulfil some argent requirement does not hold much water. If replacing Chetaks ASAP was really the goal then we should have seen Ka226 already inducted in IA by now. The same argument of urgent requirement is made for imports but the absence of alacrity shown belies the intentions. If the procedures are anyway going to take so much time despite everyone's best of the intentions then why not simply push a little more on desi programs and expedite them rather than spending money and efforts on such stupid acquisition which certainly fail to fulfil the primary intended target..??

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Re: Indian Military Helicopters

Postby Aditya G » 04 Oct 2017 12:53

Ka-226 detachable cabin presents a unique innovation possibility where several different cabins could be designed and available to units to address different needs.

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Re: Indian Military Helicopters

Postby Cybaru » 04 Oct 2017 12:57

shiv wrote:
Cybaru wrote:
The KA-226 never won in any tender ( we have discussed this before ). It always came in last or second last. Need to find the old thread and point people to read all of those things again.


Indeed we have discussed this before but I have not understood the point of the discussion on so many counts

The Jaguar was selected (over Viggen and Mirage F1) in a 20 year long DPSA saga which I followed with interest. Don't know how many BRFites are old enough to recall that saga. It was a competitive tender. It took over a decade to get anywhere and now we have an underpowered Jag that did not perform in the hills.

Another "competitive tender" was the AJT - which also lasted 20 years or so during which we lost a lot of pilots who went straight from Kiran to MiG 21 UTI trainers. The competition was between Hawk and Alpha jet

Then we had the MMRCA saga which would have lasted maybe 12-13 years before a piddly 2 squadrons join the IAF

On the other hand we had there was no competition for the Su-30 and it just landed on our shores and all of us have never stopped going gaga over that. There was never a competitive fly off for the Mi-8/Mi 17 - now considered a stellar performer and a world leader in its class. There was never a competitive tendering process for the Mi-26 whose retirement caused so much weeping on BRF and whose replacement the CH 47 caused so much teeth gnashing.

On the other hand the VVIP helicopter has a tendering process which completely collapsed and the saga is now in court with a former CAS possinbly looking at a jail term. The Mi 17 will be the new VVIP helo

Light Helos had a fly off. The Ecureil(sp?)/its cousin was chosen. The Ka 226 pulled out and then the whole tender collapsed because of reasons I cannot recall now.

The other point is that in competitive tenders it is not just performance but price also. We know now that the French probably quoted an attractive price that did not include maintenance and long term support and it became unaffordable when the fine print was examined.

Someone please explain to me what was the great advantage of a competitive tendering process that it is quoted as a great plus point when it did not occur?


Agreed.

Sorry for the delayed response and I see this has generated much conversation around this issue.

The point I was making is that is it didn't meet one part of the competition. Not to bore you since you know all of this and I agree with your point that tendering doesn't always result in optimal solution even though that is the hope. Anyways to explain, let me briefly repeat what I was trying to say; One part is one functionality, where the forces give their favorites depending on their evaluations, and the other portion when the Pricing negotiations committee meets, it reaches out to qualifying vendors to make a bid. So if this bird crashed out in the first portion of evaluation then the way I understand it is that it failed to meet the some serious milestones and got flagged by the forces. It somehow got resurrected by some magic.

Its a different matter if the PNC and vendor don't meet each others demands or something changes like in case of rafale.

Anyhow, I think the end is near especially if the LUH design gets frozen soon. That will put an end to this saga. Then some of these companies will be trying to kill IMRH! Its a dog eat dog world and no one wants a new competitor out there.

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Re: Indian Military Helicopters

Postby dinesh_kimar » 04 Oct 2017 20:53

^ I will try to answer Indranil's post, though not an expert. Below stuff is speculation.

The typical Helo gearbox is complex. (Eg. Mi-17 Gear box is heavier than the engines) .It has following features:

> to have a reduction of 1:100 within tight weight and volume limitations. For example, if gas turbine spins at 20,000 rpm, the main gear box should allow the rotor to maintain about 200 rpm.

> drive accessories like oil and hydraulic pumps

> if internal oil supply is cut off, gearbox must have "dry run" capability for 30 minutes.

> Gear boxes have a power rating. Eg. Early Seakings had gear box power limit for 2500 hp, later versions were upto 2800 hp. Corresponding engine power was 2 x 1250 / 1400 and later 2 x 1600 hp.

In case of LUH, the people at HAL are "probably" not comfortable at directly having reduction of 1: 100. This is because there are enormous stresses on gear and pinion teeth. The stresses are due to limitation of the material used for the gears (obviously indian sourced stuff will have lower stress limits compared to Euro / Khan / Rus), as well as gear tooth geometry. (papers sometimes talk abt gear tooth face width).

So HAL has opted for more conservative 3 stage reduction, even though weight will increase somewhat. Also, the no. of stages will depend on how designer plans to drive accessories like oil pumps, Tail rotor gear box, etc. which are parasitic for the Main gear Box.

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Re: Indian Military Helicopters

Postby Indranil » 04 Oct 2017 22:29

I understand the reasons for more stages. But for Dhruv they already had designed a 2-stage gear box for twice the power. There were a lot of problems with the grinding teeth as you rightly pointed out. But they fixed it.

So my question was why go back to a 3-stage gear box. Increased reliability for single engine heli?

By the way, LUH/ALH/LCH's power is limited by the gearbox at sea level. That is why, I have been asking for ALH/LCH optimized for the plains with a gear box that can handle the entire power of the engine at sea level. These slightly enlarged versions should be able to carry more fuel and payload.

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Re: Indian Military Helicopters

Postby dinesh_kimar » 04 Oct 2017 23:45

^ Saar, IMHO, HAL's fix of the gearbox is controversial.

1. A 2-stage Main Gear Box was decided during ALH design phase, when the technology collaborator (MBB and ZF Transmission, both from Germany) had little experience for such a design at the higher power ratings of Dhruv.(Apparently it is "revolutionary " large area contact gear design )

2. In 2006 and 2010, CEMILAC chief and IAF Air Marshal have talked abt "design flaws". Delivery started in 2002.

3. HAL Dhruv fleet grounded 3 times from 2004 to 2014. Dhruv speed till today is approx. restricted to abt. 240 km/h when HAL brochure promises 270 km/h. Why restrictions not lifted even today ? It points to MGB problem.

4. Consultancy done with Fiat Avio in 2011 to fix the IDS (Integrated Dynamic System) , of which , ( i think), the Main Gear Box is a part.But whether fix works or speed restrictions remain is still unknown.

5. Manohar Parrikar defended HAL Dhruv in 2015, saying "good machine" after Bolivia crash no. 4 (4 out of 7). But rumor on internet says that a component called a "cyclic" in the MGB-Rotor system was indeed the cause, and is in the Court of Inquiry Report.

6.Dhruv class helos like S-76 and EC-145 have had abt 3 crashes for a production run of 1000. The Dhruv crashed twice in 2017.

7. Another rumor says that Dhruv has no international sales because it is not Internationally certified.

8.From above learnings, it is clear that things are still unclear wrt HAL Dhruv.

Hence the 3-stage Main Gear Box.

But I dunno, all speculation onlee.

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Re: Indian Military Helicopters

Postby Indranil » 05 Oct 2017 00:50

The good thing about your speculations is that you have done your homework well.

JayS and Raghuk have seen the MGB from real close. But they can only say what they can. We have to honour that.

Regarding the IDS, I don't know if the IDS problem has been resolved completely, but significant gains have been made. Let me leave it at that.

If there was a problem with the cyclic, you wouldn't have Dhruv's carry 600 kg on a stamp sized landing spot at 20,000 feet.

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Re: Indian Military Helicopters

Postby Rakesh » 05 Oct 2017 07:57

https://twitter.com/sjha1618/status/915547801005649921 --> Army Aviation Corps must continue its current practice of inducting indigenous helicopter & forget about more Apache imports.

https://twitter.com/sjha1618/status/915547801005649921 --> It should be made up entirely of HAL Dhruv variants, Rudra, Light Combat Helicopter & the future IMRH.

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Re: Indian Military Helicopters

Postby shiv » 05 Oct 2017 08:54

dinesh_kimar wrote:^ Saar, IMHO, HAL's fix of the gearbox is controversial.

1. A 2-stage Main Gear Box was decided during ALH design phase, when the technology collaborator (MBB and ZF Transmission, both from Germany) had little experience for such a design at the higher power ratings of Dhruv.(Apparently it is "revolutionary " large area contact gear design )

2. In 2006 and 2010, CEMILAC chief and IAF Air Marshal have talked abt "design flaws". Delivery started in 2002.

3. HAL Dhruv fleet grounded 3 times from 2004 to 2014. Dhruv speed till today is approx. restricted to abt. 240 km/h when HAL brochure promises 270 km/h. Why restrictions not lifted even today ? It points to MGB problem.

4. Consultancy done with Fiat Avio in 2011 to fix the IDS (Integrated Dynamic System) , of which , ( i think), the Main Gear Box is a part.But whether fix works or speed restrictions remain is still unknown.

5. Manohar Parrikar defended HAL Dhruv in 2015, saying "good machine" after Bolivia crash no. 4 (4 out of 7). But rumor on internet says that a component called a "cyclic" in the MGB-Rotor system was indeed the cause, and is in the Court of Inquiry Report.

6.Dhruv class helos like S-76 and EC-145 have had abt 3 crashes for a production run of 1000. The Dhruv crashed twice in 2017.

7. Another rumor says that Dhruv has no international sales because it is not Internationally certified.

8.From above learnings, it is clear that things are still unclear wrt HAL Dhruv.

Hence the 3-stage Main Gear Box.

But I dunno, all speculation onlee.


In the interests of clarity I would like to raise several questions about this post
1.
2. In 2006 and 2010, CEMILAC chief and IAF Air Marshal have talked abt "design flaws". Delivery started in 2002.
What part of the statement connects to the gearbox

2.
HAL Dhruv fleet grounded 3 times from 2004 to 2014. Dhruv speed till today is approx. restricted to abt. 240 km/h when HAL brochure promises 270 km/h. Why restrictions not lifted even today ? It points to MGB problem.
This does not necessarily connect with a gearbox problem. In fact airspeed is not the only thing that stresses the gearbox. The engine is put under heavy stress at very high altitudes. On the other hand a lot of aircraft have two different data points. One is "maximum speed achievable" and "maximum speed which should not be exceeded"

3.
Manohar Parrikar defended HAL Dhruv in 2015, saying "good machine" after Bolivia crash no. 4 (4 out of 7). But rumor on internet says that a component called a "cyclic" in the MGB-Rotor system was indeed the cause, and is in the Court of Inquiry Report.


You are holding up and internet rumour against what Parikkar said as an argument. Please provide a source quote and say what a "cyclic" component of a gerabox might be.
4
6.Dhruv class helos like S-76 and EC-145 have had abt 3 crashes for a production run of 1000. The Dhruv crashed twice in 2017.

Both 2017 crashes were weather related. What has that got to do with the gearbox?

5.
7. Another rumor says that Dhruv has no international sales because it is not Internationally certified.

Rumour? And how does that connect to the gearbox?

6.
8.From above learnings, it is clear that things are still unclear wrt HAL Dhruv.

There is nothing to learn from your post and nothing to prove about the gearbox. Please educate me on the learnings I have missed.


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