Simply put , the issue at hand is that Indian army does not trust DRDO or Indian suppliers , and elements within the Army choose foreign suppliers over Indian ones.
Army has the least capital intensive of defence hardware , but breaking the mould with the army is impossible , they don't invest in any local R&D and are not big when it come's to local orders , although there are exceptions.
Take this for example But TATA and MAhindra have made a wide variety of things for the Army mostly transports , trucks and such have actually been accepted. But when they actually made defence equipment such as armoured vehicles , they are still trying to get them inducted on a large scale yet the army simply has not shown enough interest.
Frankly if you ask me , TATA and Mahindra between them can offer Everything from armoured vehicles , to tanks and artillery(Mahindra/BAE systems).
All the India army has to do is show interest.
IAF shared the army view up until a few years ago , now it readily embraces Indigenous products , it has even started to invest its time , efforts and money into local R&D , LCH for example . It has even asked Private companies to design UAV's but has yet to offer any financial assistance as they are still unproven. Keep in mind this is the most , if not the second most capital intensive sector of the forces , when it comes to weapons develop , not many players have the cash to break the mould here , but there are players who are doing it and the IAF if not cooperative , has at least been responsive.
as their is more investment and Private sector firms can afford to do R&D(which is an eventuality) , IAF will no doubt show positive attitude towards it.
IN , if you actually look into it , does have a very good indigenous arsenal , IN works with both the Public and private sector firms as need be. everything from manufacturing to design work. INS Arihant , the navy's most advanced vessel was in fact built with the help of L&T , i am not sure about their exact involvement , but i was informed they played a major role. But ship design as you would expect. Now L&T is designing patrol boats for the Navy. IN is doing it right , taking things at its own pace , in fact in the Navy it is the lack of infrastructure that is the hindrance rather than the chronic lack of initiative found in the other two branches. India can't do modular shipbuilding due bad infrastructure between ports and yards , IN goes for foreign systems because All of India's shipyards are filled with orders can't take any more , and can't build them fast enough to meet IN needs. Keep in mind however this is the most capital intensive of weapons development. Building the ships and trying to make the infrastructure needed to make, that takes a lot of cash , more than what IN or any company can afford out of the blue.
There you have it , but keep in mind however India private sector companies do also manufacture weapons , while they may not develop them , on this note Every one wants to see more of , Private sector manufacturing is going up , and people are pushing for more of it , and the offset clause only makes the picnic even better. It's only because of the profits made in manufacturing are the private sector firms considering going into weapons development , as they establish themselves and their QoS , they may receive more government support , but as of now the trend is positive.
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You ask what can be done to speed up this process , get a copy of DRDO budget for the year, create a new department with in the MoD, call it the commie of weapons development or whatever , that is made up for both MoD and military leaders. Distribute that money amongst the three branches. Invite all players in the private sector , and then offer them the money.
How will this work , simple much like a contest , these companies have an opportunity to come up with systems , that suit the refurbishments of the armed forces , and then present their systems. They may secure funding from 1, 2 or all 3 branches as a result. As a result the branches have a stake on whatever is developed but they don't have to put their budget on the line. Private sector gets the funding much like a scholarship , they may use it as they see fit , if they can do their research for less , the remainder is their profit. then again if their initial bid for finding was also low , then they have a better chance of getting it. Who the branches may even want to use their own budget to finance some of these projects.
As you can imagine all thins will create a very competitive , efficient and effective system , every buck will count , every day late could mean the end of their funding , these guys make a profit selling their guns , not the actual funding , that is only to subsidize their research.
In fact Company;s may well end up submitting lower bid's in order to secure funding and cooperation , develop systems and make a profit selling them latter.
Well that is my idea , any way. with sufficient research and proper procedure i am sure you can make a proper system , like i described.