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.