Indian Military Helicopters

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JayS
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Re: Indian Military Helicopters

Post by JayS »

Karan M wrote:JayS, what you are supposing is that only this demo saw three people on the boom. What if this has happened repeatedly because therebwas sone sort of miscommunication that >2 people could be on the boom. And if this occurred repeatedly wouldn't the metal age/ fatigue faster? Could that be a reason, and cant SOPs be changed.

Indranil the answer needs to be out on Twitter because this is arguably a very bad indictment afainst HAL QC otherwise.
Karan, I am questioning the wisdom in designing and qualifying the rope system for only two persons at a time (which is what Indranil is pointing to) precisely considering the real life limitations on maintaining such SOP in strictest sense, especially in the actual war scenarios. There are multiple photos/videos which shows Dhruv has seen more than 2 persons on the rope in past. As I understand the separation in soldiers on rope is followed to avoid collisions. In my limited google search I could not find any reference to "design limits of insertion system putting limits on number of people on rope".

Having an SOP of two soldiers on rope by Indian Army does not/should not imply "HAL designed the system only for 2 persons". If HAL indeed do this then the wisdom behind this design decision is very much questionable. I would think its rather in favor of HAL not to point out that the boom was only qualified for 2 people. Because that's an absurd thing to do on the designer's side. Why would anyone design it only for 2 persons when designing it for even 4 or 6 is not going to add to the weight any significantly while making the design far more robust..?
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Indranil wrote:
Rakesh wrote:https://twitter.com/sandeepunnithan/sta ... 6839389185 --> Chopper fall medical situation report. Commando #3 discharged on second day. Commando #2 - some months - back injury. Commando #1 minor injury. Para SF rules!

https://twitter.com/reachanshul/status/ ... 2617925633 --> Sandeep, looks like the 3rd commando fell on the 2nd one and part of the boom landed on both. Wish them an early and full recovery. Also a relook at SOPs.

https://twitter.com/sandeepunnithan/sta ... 1288084480 --> Yes. Hence the serious nature of #2's injuries. He'll be out in a few months hopefully.
The best news I have read. With Sandeep U reporting, I can trust it. Otherwise, the news on the condition of the jawans has been all over the place.

I had a sliver of hope when I saw the third guy fall. He was neither vertical nor horizontal, which is the best position to absorb shock.
My biggest fear was a spinal injury. I'm worried about Commando 2. That can have very serious consequences and even make a young strapping man into a life long parapalegic. So lets hope that none of that happens. I am an informal patron of the Parapalegic Centre in Pune and have had the immense privilege of being a small contributor to them and being invited as chief guest for a RD ceremony many years ago. The spirit of those men brought tears to my eyes - I saw them playing basket ball on wheel chair with such josh. They do not get much govt support so all work is done by donations and its a constant struggle for the Director to get donations. Do please donate if you can. You will not find a better avenue for donating.

Here is a link to a Patriot program which has some men from the Parapaelgic Centre who have come to train for para olymipcs. It doesnt show the PRC but shows some men from it. https://www.youtube.com/watch?v=AvVEm5ppPtg
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

This episode shows brings one thing out in the open to the general public - armed forces has signficant professional dangers and they can strike in all circumstances - war, not war/not peace, peace, training, demos. This episode is generating some coverage but hundreds of episodes like these keep happening all the time in course of the complex and very challenging operations the armed forces carry out.
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Here is the link to the program on the Parapalegic Rehabiliation Centre. Do watch this all.

https://www.youtube.com/watch?v=Q_8z7ntN31I
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Re: Indian Military Helicopters

Post by Rakesh »

Akshay-ji: Is there a website link for donation?
Akshay Kapoor
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Here are the contact details

Website: http://www.para-rehab.org, http://www.rehab-center.in/paraplegic-r ... entre-pune


Address:
Paraplegic Rehabilitation Centre,
Range Hills,
Kirkee, Pune-411020

Mobile/Phone Number: 3191(Army) / 020-2602 3191 (Civil)


Email: prckirkee1974@gmail.com
Akshay Kapoor
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Rakesh wrote:Akshay-ji: Is there a website link for donation?
You can email them on prckirkee1974@gmail.com
Indranil
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Re: Indian Military Helicopters

Post by Indranil »

Thank you for the information about the center. I will do my little bit.

By the way, I think we should create a sticky thread for information of organizations like the above. It would enable easy reference for the future.
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Re: Indian Military Helicopters

Post by Indranil »

Jay,

I don’t see your point.

How do you know that the 2-man decision was unilateral? At the very least, the armed forces accepted the boom with the restriction. How difficult would it be to specify 2 is not enough, we need 3. And how difficult would it be for HAL to redesign the boom for 3?

We don’t know everything that transpired. So, let’s not assign blame without knowing.
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Indranil wrote:Jay,

I don’t see your point.

How do you know that the 2-man decision was unilateral? At the very least, the armed forces accepted the boom with the restriction. How difficult would it be to specify 2 is not enough, we need 3. And how difficult would it be for HAL to redesign the boom for 3?

We don’t know everything that transpired. So, let’s not assign blame without knowing.
I don't think he is assigning any blame Indranil. Quite the opposite.

And this so called '2 man' restriction does sound rather low. All operational parameters have built in safety margins because you can never be sure what will transpire in ops, what the environment or the enemy will do so SOPs are always designed to be safer than equipment safety margins (in extreme situations in war these SOPs will be breached). Assuming (and we have no idea what transpired) If equipment load limit itself is just 2 men then how can SOP be designed for incorporating a safety margin ?

Slithering IS NOT a special forces only exercise , it is an increasingly routine infantry (in fact all arms) execrcise because that is a very good way of inserting troops. As many as 10-20 % of troops could have been trained for slithering (SF is less than 1 %). I know for a fact that Dhruv is increasingly being used in this role. In fact it is becoming a workhorse of the army aviation and I just find it difficult to believe that there could be a 2 person limit. I just dont see how it would work from an operational perspective. Its simply not practical.
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Indranil wrote:Thank you for the information about the center. I will do my little bit.

By the way, I think we should create a sticky thread for information of organizations like the above. It would enable easy reference for the future.
Thank you very much. Everything helps. It also gives them a morale boost that people care. Good idea re the sticky. I will contact you on the admin net.
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Re: Indian Military Helicopters

Post by ramana »

So lets look at primary causes of the recent ALH boom failure leading to the injury of the three soldiers.

1) The boom overloaded and broke the attach bracket
2) Substandard material leading to the failure in the boom attach bracket
3) Fatigue loading caused the boom bracket failure
4) Inherent design flaw leading to the boom bracket failure. Composite and metal joint interface caused the excess tension load leading to failure.

What else?
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Re: Indian Military Helicopters

Post by Indranil »

Here is my list of things that could have gone wrong:

1. Incorrect requirement specification
2. Incorrect design
3. Incorrect choice of material
4. Incorrect QC at delivery
5. Incorrect maintenance
6. Incorrect SOP

Does anybody here know what combination of the above lead to the accident? Does anybody know who manufactures the boom, who does the regular maintenance checks? If not, why jump to blaming HAL: Convenience?
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Re: Indian Military Helicopters

Post by Indranil »

Very interesting:

Rahul Singh reports that they went ahead with slithering exercise at Army Day parade 2018!

https://twitter.com/rahulsinghx/status/ ... 4895201281
Image
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Indranil wrote:Very interesting:

Rahul Singh reports that they went ahead with slithering exercise at Army Day parade 2018!

https://twitter.com/rahulsinghx/status/ ... 4895201281
Image
Koi shaque ? Its the fauj...ops dont stop because of accidents.
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Re: Indian Military Helicopters

Post by Karan M »

JayS wrote:
Karan M wrote:JayS, what you are supposing is that only this demo saw three people on the boom. What if this has happened repeatedly because therebwas sone sort of miscommunication that >2 people could be on the boom. And if this occurred repeatedly wouldn't the metal age/ fatigue faster? Could that be a reason, and cant SOPs be changed.

Indranil the answer needs to be out on Twitter because this is arguably a very bad indictment afainst HAL QC otherwise.
Karan, I am questioning the wisdom in designing and qualifying the rope system for only two persons at a time (which is what Indranil is pointing to) precisely considering the real life limitations on maintaining such SOP in strictest sense, especially in the actual war scenarios. There are multiple photos/videos which shows Dhruv has seen more than 2 persons on the rope in past. As I understand the separation in soldiers on rope is followed to avoid collisions. In my limited google search I could not find any reference to "design limits of insertion system putting limits on number of people on rope".
Typically, the design would have followed SQR which means the item either flowed directly from the SQR or was a result of any other SQR driven requirement, either way, it would be signed off by all stakeholders. I suspect it was not an issue all these days, because of the SOP, of using a second attachment point. Somewhere, in operations, it was discovered that SOP caused a time delay or was inconvenient and hence it was changed, precipitating this incident. Of course, this is all speculation at this point and the IA will find the real reason working with HAL.

To get back to my original point, If you have an engine power rating specified which means an engine of some weight, and so forth, and that means a bracket of some weight/rating, the designer would take the decision and services would not be so interested. Its the designers issue after all, but in an issue like deciding how many people on a hoist, there is no way HAL would take that decision on its own. That information has to come from the user.
Having an SOP of two soldiers on rope by Indian Army does not/should not imply "HAL designed the system only for 2 persons".
It typically would, because one thing I have realized about our designers & institutions is they are very risk averse about overpromising given past issues and hence will follow the SQR to the T.

Take the Tejas having R60 vs R73E for instance.
If HAL indeed do this then the wisdom behind this design decision is very much questionable. I would think its rather in favor of HAL not to point out that the boom was only qualified for 2 people. Because that's an absurd thing to do on the designer's side. Why would anyone design it only for 2 persons when designing it for even 4 or 6 is not going to add to the weight any significantly while making the design far more robust..?
Its hardly absurd, its sticking to the mandate very precisely and then what happens thereafter is another story altogether.

Wherever the designers decide to "out think" the SQR there is a tradeoff elsewhere and getting that cleared means more paperwork, more permissions from the services, more cribbing through out the design chain and your own people, easier to stick to a narrow mandate and be done with it.

Which is what makes the requirements projection so crucial.
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Re: Indian Military Helicopters

Post by Karan M »

Akshay Kapoor wrote:
Indranil wrote:Very interesting:

Rahul Singh reports that they went ahead with slithering exercise at Army Day parade 2018!

https://twitter.com/rahulsinghx/status/ ... 4895201281
https://pbs.twimg.com/media/DTkEhxIU0AUUK6m.jpg

Koi shaque ? Its the fauj...ops dont stop because of accidents.
Akshay, what I think Indranil means is the issue has been found out or they have a good idea why it occurred, and hence they went forward with it after taking corrective measures.
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Not necessarily, infact almost certainly not because the issue cannot be found so quickly. They went ahead because the show goes on. Investigations will continue in parallell.

Of course Indranilji in his wisdom can come to any conclusion that suits him - blame the 'SOP ' and teach the army about slithering and correct 'specifications'.
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Re: Indian Military Helicopters

Post by Karan M »

Akshay - I draw a parallel to any unforeseen crash by IAF planes. They are grounded till the COI brings up its recommendations &/or the initial investigation suggests measures can be taken to add to the safety factor & hence prevent such an issue.

In this case, I suspect, IA-HAL have come to a preliminary understanding of what has happened, and quick checks have been made with IA folks doing slithering on ALH & checks done on ALHs available for this op, hence it was decided to go ahead.

Show could have gone on with other options IMHO - but IA will not unnecessarily risk its troops with faulty equipment which genuinely has potential to put its troops at risk. Since, this is just a demo and not wartime to justify such measures.

There could have been some other chopper brought in to do slithering ops, eg Mi-17
http://4.bp.blogspot.com/-jZb28XJzJLY/T ... BMar12.jpg

Hence my (and I suspect Indranil's optimism), that this is issue has been narrowed down to a bunch of likely suspects and SOPs have been (temporarily) modified for greater safety.
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Re: Indian Military Helicopters

Post by Karan M »

Also ALH is being given pride of place, by IA IMHO to correctly demonstrate to the powers that be, how many important acquisitions are from domestic sources. By undertaking this op the very next day, when IA could have justifiably pulled out the ALH, is a big boost for both ALH and HAL.

I hope HAL realizes this vote of confidence and reciprocates by continuing its focus on improving serviceability of ALHs and other items sold to services. Also LUH needs to be accelerated. In pre IA day speeches Chief openly said Ka-226 delay is hurting services. This should accelerate that program & which means HAL also better get cracking on the LUH.
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Re: Indian Military Helicopters

Post by Indranil »

Akshay sir, please no "ji" for me. I am just uncomfortable with salutations.

My argument is simple: let's not pin faults. If pinning the fault on the Armymen without knowing is not correct, then so is pinning the fault on HAL's men! None of us here are blaming anybody yet, which is good. I wish we ask the guys jumping up and down on Twitterland on what basis are they pinning faults?

Army's decision to go ahead with slithering is interesting because there were reports that IA had suspended slithering ops from Dhruv. The show could have gone on with quick injection without slithering. In fact, slithering is a slow and risky process when you don't have a clearing to set the heli down. Otherwise, it is much faster and safer to just set the heli down momentarily, everybody jumps off and the heli flies away.
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Re: Indian Military Helicopters

Post by Indranil »

Karan M wrote:Also ALH is being given pride of place, by IA IMHO to correctly demonstrate to the powers that be, how many important acquisitions are from domestic sources. By undertaking this op the very next day, when IA could have justifiably pulled out the ALH, is a big boost for both ALH and HAL.

I hope HAL realizes this vote of confidence and reciprocates by continuing its focus on improving serviceability of ALHs and other items sold to services. Also LUH needs to be accelerated. In pre IA day speeches Chief openly said Ka-226 delay is hurting services. This should accelerate that program & which means HAL also better get cracking on the LUH.
Absolutely. LUH flight testing is actually proceeding quite smoothly.
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Re: Indian Military Helicopters

Post by srai »

3-ways to slither down a Dhruv -

1. Slithering from the rear side
Image

2. Slithering from the other side
Image

3. Slithering from the boom extension
Image
Last edited by srai on 16 Jan 2018 05:31, edited 1 time in total.
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Re: Indian Military Helicopters

Post by Karan M »

^^ Yes, but they went ahead with the side door slithering on IA day 2018. Pic above.
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Re: Indian Military Helicopters

Post by srai »

Indranil wrote:Very interesting:

Rahul Singh reports that they went ahead with slithering exercise at Army Day parade 2018!

https://twitter.com/rahulsinghx/status/ ... 4895201281
Image
It looks like Dhruv is hovering a bit lower than the accident video. Also, it looks like they are doing one man at a time.
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Re: Indian Military Helicopters

Post by Indranil »

srai wrote:3-ways to slither down a Dhruv -

1. Slithering from the rear side
Image
This one is actually part of the extraction and not injection. Situation again is as follows. The heli cannot land. So it lowers the ropes from the back. Dhruv can actually lower two ropes. Up to 3 men attach themselves to each of these ropes. If you see carefully, you can see that they don't need to hold on to the rope. The heli flies away with them.
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Re: Indian Military Helicopters

Post by Indranil »

srai wrote: It looks like Dhruv is hovering a bit lower than the accident video. Also, it looks like they are doing one man at a time.

In the accident video, there were somethings which looked at a little different to my untrained eye than other demos. I don't know if they contributed to anything, but here are the thoughts that are rambling in my head.

1. The heli was little higher than typical. In fact, it gains about 10 feet after the rope is first thrown down. This increases the length and time of the descent. But, they must be practicing it because the injection may be in a jungle where the heli can't get lower.
2. The men were actually 2nd 3rd and 4th to exit the heli. If you notice carefully soldier #2 for some reason was much slower than #1 and #3. Soldier #3 actually slowed down for #2 about half way down the rope. When soldier #4 started to slither down the boom gave way.

And ofcourse there could be QC/design/maintenance issues. We don't know what all factors contributed to the accident.
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Re: Indian Military Helicopters

Post by ashishvikas »

Rudra !!

Image

https://ibb.co/iXmzgm

Can someone please tell me how to upload image ? I tried to use "Img" option but it doesn't seems to be working.

Admin Note: Fixed. The original link does not point to a pic format file, hence the image tags wont pick
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Re: Indian Military Helicopters

Post by JayS »

Indranil wrote:Jay,

I don’t see your point.

How do you know that the 2-man decision was unilateral? At the very least, the armed forces accepted the boom with the restriction. How difficult would it be to specify 2 is not enough, we need 3. And how difficult would it be for HAL to redesign the boom for 3?

We don’t know everything that transpired. So, let’s not assign blame without knowing.
I did say if the system with restrictions was accepted by IA, IA is equally responsible as much as HAL. It makes no sense to me. I cannot think why would the system be designed and qualified for only 2 people or should have the restriction still. This is not a newly deployed system by any means. Been there for years.

Also, let me also state again - I am not talking anything against having an SOP for 2 soldiers on the rope at a time - it makes sense from operational point of view. You indicated that the rope boom itself is qualified only for 2 persons. I cannot digest that part. Please anyone make me understand that.

And to repeat myself again - having designed it for 2 folks, it should still not have failed with repeated use with 3 persons on it. The design condition is always the worst possible already (e.g. in this case, 2 soldiers of 95percentile weight with maximum possible combat load in any perceivable operation which would be easily 250kg total. In real life most of the times even 3 combat ready soldiers would be under this weight, let alone 3 soldiers practicing without much load) and then there are all sort of factors on it increasing effective FoS. And please do not think that regularly having more than 2 soldiers is a valid cause for failure. Its not because the design itself is designed for Fatigue with worst design loading condition considered as a repetitive cyclic load everytime. In real life any component is subjected to much lesser loads.

The failure is not of design or SOP, IMO. It was material failure, more likely due to quality control issue or maintenance issue. HAL is not the only organization in the world which would have such issues. The best of the best OEMs cannot eliminate 100% issues else we would have seen ZERO accidents in the world in any engineering field. Or IA ground supporting staff won't be the worst maintenance crew in the world if this is on their part. It could be either of them. HAL is more likely the one which will have to take corrective action.
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Re: Indian Military Helicopters

Post by JayS »

Indranil wrote:
srai wrote: It looks like Dhruv is hovering a bit lower than the accident video. Also, it looks like they are doing one man at a time.

In the accident video, there were somethings which looked at a little different to my untrained eye than other demos. I don't know if they contributed to anything, but here are the thoughts that are rambling in my head.

1. The heli was little higher than typical. In fact, it gains about 10 feet after the rope is first thrown down. This increases the length and time of the descent. But, they must be practicing it because the injection may be in a jungle where the heli can't get lower.
2. The men were actually 2nd 3rd and 4th to exit the heli. If you notice carefully soldier #2 for some reason was much slower than #1 and #3. Soldier #3 actually slowed down for #2 about half way down the rope. When soldier #4 started to slither down the boom gave way.

And ofcourse there could be QC/design/maintenance issues. We don't know what all factors contributed to the accident.
These things should not have any role in the failure event. If not that day, it would have failed next time or shortly after.
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Re: Indian Military Helicopters

Post by JayS »

Karan M wrote:Also ALH is being given pride of place, by IA IMHO to correctly demonstrate to the powers that be, how many important acquisitions are from domestic sources. By undertaking this op the very next day, when IA could have justifiably pulled out the ALH, is a big boost for both ALH and HAL.

I hope HAL realizes this vote of confidence and reciprocates by continuing its focus on improving serviceability of ALHs and other items sold to services. Also LUH needs to be accelerated. In pre IA day speeches Chief openly said Ka-226 delay is hurting services. This should accelerate that program & which means HAL also better get cracking on the LUH.
Couldn't agree more. IA's confidence in the ALH deserves respect. I am pleasantly surprised to see the Heli insertion still being demonstrated. We need this kind of support and backing for all our desi programs.
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Indranil wrote:Akshay sir, please no "ji" for me. I am just uncomfortable with salutations.

My argument is simple: let's not pin faults. If pinning the fault on the Armymen without knowing is not correct, then so is pinning the fault on HAL's men! None of us here are blaming anybody yet, which is good. I wish we ask the guys jumping up and down on Twitterland on what basis are they pinning faults?

Army's decision to go ahead with slithering is interesting because there were reports that IA had suspended slithering ops from Dhruv. The show could have gone on with quick injection without slithering. In fact, slithering is a slow and risky process when you don't have a clearing to set the heli down. Otherwise, it is much faster and safer to just set the heli down momentarily, everybody jumps off and the heli flies away.
I haven’t pinned fault on anybody. Neither has Jay S. In fact I have taken this in stride and said this happens. Can’t be helped. If we can improve we will, if it’s a freak incident so be it. Ops will certainly not stop / slithering happens regularly in ops and as I pointed. Dhruv is a mainstay of AAC and pilots and men have
full confidence in the machine. I will share some videos on that later.

But it’s wrong to start questioning SOPs without having any tactical knowledge or experience. That’s a lazy DDM response - let’s look at SOP. Adds nothing to the discussion and just shows ignorance. For clarity I am not calling you ignorant but am calling DDM that. Let’s not use their shortcuts here.

And lastly why bring twitter here. We have a higher standard of discussion - why vitiate it by extending twitter war here. We have a higher standard to keep.
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Re: Indian Military Helicopters

Post by Akshay Kapoor »

Re videos - look at Mission Army Episode 6

And NDTV Watan Ke Rakhwale episode on Dhruv/ Army Aviation Corps.
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Re: Indian Military Helicopters

Post by JayS »

Just doing some googling. I find something which I didn't see before. May be it answers my question to some extent. But can't say for sure.

Rope insertion System for Bell helicopters. It allows 4 persons at a time on each side.

https://www.aero-access.com/products/be ... e-kit.html

Another. These are capable of 300lbs load at a time on one side. This is telescopic boom which can be retraced inwards when not in use.

https://www.aero-access.com/products/be ... e-kit.html
https://www.aero-access.com/products/be ... e-kit.html

FRIES rope specs by one of the suppliers (its reasonable to assume IA uses similar ropes)
https://www.marlowropes.com/product/fri ... ion-system
https://www.marlowropes.com/system/file ... download=1

Breaking load is 7600kg..!! Max length 120ft. There are other suppliers with even 30000lbs breaking strength ropes.

Wiki page on Fast roping or FRIES: https://en.wikipedia.org/wiki/Fast-roping
Several people can slide down the same rope simultaneously, provided that there is a gap of approximately 3 metres (9.8 ft) between them, so that each one has time to get out of the way when they reach the ground.
Will keep adding links here.

Another link to USMC doc on procedures for various rope insertion techniques including rappelling and FRIES. The one which IA uses on ALH (under current discussion) is FRIES technique.
https://www.globalsecurity.org/military ... ndated.pdf

Page 78 mentions (what Indranil previously said previously) - 600lbs load limit for couple of helis and for third its 2 soldiers at a time on the rope. But note that for one heli atleast the limit is due to quick release mechanism. As such the links are the weakest parts which is expected. Even for the ropes the steel joints for end attachment are considerably weaker than the ropes themselves.

Another pointer from same doc - Inspection interval mentioned for one type of frame:
(2) The frame shall undergo a non-destructive inspection (NDI) at the completion of 500 descents or at the end of a six month inspection cycle, which ever occurs first. The frame shall be inspected for:
(a) Condition of all hardware (i.e. pins, cables)
(b) Condition of all welds for signs of cracks or fatigue.
(c) Condition of steel tubing for signs of buckling, bending, rust, or deformation.
(d) Conduct a Magnetic Particle Inspection for cracks, fatigue, and stress at all joints, welds, and stress points.

(3) Repair and re-inspect any discrepancies or reject the bad frame.
So it seems the load limits for FRIES are similar as mentioned by Indranil for other helis.

Two factors which I did not consider before - impact on Heli CG and weight imbalance (one sided hanging weight would make heli roll on one side). There is one more factor I did consider but thought of it as unlikely candidate - the main heli aero-structure to which the rope boom is attached itself might have limitation.

However let me also state that this still does not explain failure that we saw. Pointing fingers towards design or procedural lapse, both are extreme and equally uncalled for IMO.
Austin
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Re: Indian Military Helicopters

Post by Austin »

Interesting. IAF Mi-17 at NSG Manesar today demos GIGN gear- AirTEP meant for insertion/extraction/ rescue of 12 persons at a time.

Video: https://twitter.com/SandeepUnnithan/sta ... 7970493440
shiv
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Re: Indian Military Helicopters

Post by shiv »

Indranil wrote:Here is my list of things that could have gone wrong:

1. Incorrect requirement specification
2. Incorrect design
3. Incorrect choice of material
4. Incorrect QC at delivery
5. Incorrect maintenance
6. Incorrect SOP
7. All might have been correct but this was a black swan event


Does anybody here know what combination of the above lead to the accident? Does anybody know who manufactures the boom, who does the regular maintenance checks? If not, why jump to blaming HAL: Convenience?
There.. corrected.

"Blame" is a word that really should not be used by anyone until the investigation is done. Sometimes shit happens - that boom gets overstressed one day and breaks with a normal load 2 months later when inspections (if any) are not due yet. So why not stop talking "blame" and "incorrect this or that" and simply continue to be clever clogs and forensic experts minus the fault finding. We seem to have simply shifted the goalpost from "heads must roll" to "who/what is to blame"

May I ask for the first time on BRF who got fired for the Challenger disaster? Who was to blame? Which heads rolled in heaven's own hinterland?
Singha
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Re: Indian Military Helicopters

Post by Singha »

>>in heaven's own hinterland?

:rotfl:

***t is always going to happen in high risk military stuff. a good org will learn from it and fix it while bad ones will try to hide it. our successes and failures in india on all fronts are open to all, and for good or bad thats how we do things. there is also accountability to civilian oversight rather than a huge mil-ind complex running their own well funded , walled garden deep state.

cheen despite its fire and flame has not published the kind of launch videos we do, while patronisingly rolling down TELARs on parade and trying to rattle bars of the cage.
hnair
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Re: Indian Military Helicopters

Post by hnair »

IIRC, chiefs of Canaveral and Marshall space centers were asked to go. Morton Thiokol had major shakeups, as the SRB contractor. NASA's SRB program boss resigned after reports came out of a meeting , just before the day before launch where some Morton Thiokol's technicians pointed that there is abnormal freezing at the pad, that was not tested out.

Almost all resigned, only after the preliminary inquiry reports started coming in. So where we err, is the timing of our demand for resignation. Immaturely, we want immediate resignations ("that is what happens in my office, when customer Cindy's medical report got leaked"), instead of a thorough inquiry, where people can speak up. But once again, we are opening up for that ridiculous head-rolling discussion which is over!

We hopefully will know why this happened, considering there is this photo posted above by srai, which shows that along with the boom that snapped off, the rope is anchored on either the floor or pillar of the Dhruv. Did that anchoring also not work after the boom broke off?

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JayS
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Re: Indian Military Helicopters

Post by JayS »

Karan M wrote:
JayS wrote:
Karan, I am questioning the wisdom in designing and qualifying the rope system for only two persons at a time (which is what Indranil is pointing to) precisely considering the real life limitations on maintaining such SOP in strictest sense, especially in the actual war scenarios. There are multiple photos/videos which shows Dhruv has seen more than 2 persons on the rope in past. As I understand the separation in soldiers on rope is followed to avoid collisions. In my limited google search I could not find any reference to "design limits of insertion system putting limits on number of people on rope".
Typically, the design would have followed SQR which means the item either flowed directly from the SQR or was a result of any other SQR driven requirement, either way, it would be signed off by all stakeholders. I suspect it was not an issue all these days, because of the SOP, of using a second attachment point. Somewhere, in operations, it was discovered that SOP caused a time delay or was inconvenient and hence it was changed, precipitating this incident. Of course, this is all speculation at this point and the IA will find the real reason working with HAL.

To get back to my original point, If you have an engine power rating specified which means an engine of some weight, and so forth, and that means a bracket of some weight/rating, the designer would take the decision and services would not be so interested. Its the designers issue after all, but in an issue like deciding how many people on a hoist, there is no way HAL would take that decision on its own. That information has to come from the user.
Having an SOP of two soldiers on rope by Indian Army does not/should not imply "HAL designed the system only for 2 persons".
It typically would, because one thing I have realized about our designers & institutions is they are very risk averse about overpromising given past issues and hence will follow the SQR to the T.

Take the Tejas having R60 vs R73E for instance.
If HAL indeed do this then the wisdom behind this design decision is very much questionable. I would think its rather in favor of HAL not to point out that the boom was only qualified for 2 people. Because that's an absurd thing to do on the designer's side. Why would anyone design it only for 2 persons when designing it for even 4 or 6 is not going to add to the weight any significantly while making the design far more robust..?
Its hardly absurd, its sticking to the mandate very precisely and then what happens thereafter is another story altogether.

Wherever the designers decide to "out think" the SQR there is a tradeoff elsewhere and getting that cleared means more paperwork, more permissions from the services, more cribbing through out the design chain and your own people, easier to stick to a narrow mandate and be done with it.

Which is what makes the requirements projection so crucial.
Karan, SQR only specifies certain requirement and not how it is to be achieved. That's a designer's decision. Also lets not compare this with something like an engine bracket. Engine bracket design has far more involved design methodology. This particular bolted joint we are talking about can be easily designed with hand calculations based on simple conservative formulae. There is hardly any performance penalty by increasing load from say 200kg to 400kg. Its not going to increase weight by much, perhaps couple of kilos more on the metal component which failed.

Anyways, I have been trying to get the thing cleared that its highly unlikely to be a design issue, even if we consider its only designed for 2 person's load. I posted above, other references that show that's a valid design choice with some possible constraints forcing such decision and I stand corrected on that point. But at the same time I have noted that the weak links are the small metal links/clips, attachment points of rope to boom etc. Rope itself is pretty strong and I am very sure that the metal/composite components such as the boom itself are also far more conservatively designed.
srai
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Re: Indian Military Helicopters

Post by srai »

hnair wrote:...

We hopefully will know why this happened, considering there is this photo posted above by srai, which shows that along with the boom that snapped off, the rope is anchored on either the floor or pillar of the Dhruv. Did that anchoring also not work after the boom broke off?

Image
Valid point.

Here are more closer side views:
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