Why would you provide cover, for a trainer, when you can do the same for an LCA MK1 or a Jag, that both have far better CAS capabilities?
Because we don't have enough of either. Many of the Jags are going to be retired, a grand total of 0 Tejas are in service, at most 40 will be in service in a few years, and even today, before the retirement of Jags and mig-27s, we are short of squadron strength. If it was a choice between 100 Hawks and 100 LCAs, I would take the LCAs. But the choice is between 100 Hawks and 40 LCAs in future, or 0 Hawks and 40 LCAs in future. With the paucity of numbers, I would choose 100 Hawlks+40 LCAs.
So the choice you have presented is not he choice facing the IAF today.
Why would you provide cover for a trainer, when an upgraded Mig can do the strike itself, while being fully able to defend itself?
Upgraded mig-29 can, but we have only 60 of them. The mig-27s and jags still need cover, and even the mirages did. So what is the harm in providing cover to Hawks when mig-27s retire?
Why would you take away the only benefit of using the a trainer in combat missions, it's low costs, by adding costs for fighters that needs to cover it?
The aircrafts that is will replace also need fighter cover. Until we have enough multirole aircrafts, there is no choice but to provide fighter cover for strike aircrafts. What would be more expensive - a mirage or Jag escorted by Sukhois, or a Hawk escorted by Sukhois? The fighter cover costs the same in both. But the trainer is cheaper than cutting edge aircrafts, for light strike missions, when needed.
Not to mention that they don't have any EW / countermeasure capability and you know what happend the last time we used aircrafts with limited capabilities in CAS.
You mean the helicopter that was shot down by a portable SAM? Sure, but that's not what we are going to do, is it? Unless it is in CI, the hawks will be escorted by Sukhois which can provide EW in the battlespace.
COMBAT FIGHTER squadrons, not trainer squadrons and a Hawk is not even close equal a Jag, let alone any of the multi role fighters.
I know Hawk is not as capable as a jag, but it is more capable than zero jags. In other words, better than nothing. It's not like if we decide not to arm a hundred hawks, we will get a 100 jags in place of those. It's not either or. Many jags and all mig-27s have to retire soon, there is no way around that. We will lack strike capability, that is a fact. The hawks can provide some strike capability for a low cost.
That's a myth! There are currently only 4 squads of Mig 27s left in the fleet and all of them are already under replacement by MKIs (the 2 upgrade squads most likely by the 2 upgraded MKI squads we ordered). The Jags will be even upgraded now, to serve well beyond 2025, so doesn't need replacements either and we are adding multi role fighters that adds to the strike capabilities anyway (3-4 MKI squads till 2019, 2 x LCA MK1 squads till 2019, hopefully 1 x MMRCA squad till 2019). So there is neither a need to replace strike fighters, nor is there a lack of strike capability in the fleet!
There are 80 mig-27s and a few squadrons of very old jaguars that are on the verge of retirement. Not all Jags were upgraded, because it was uneconomical to upgrade the ons nearing the end of their service lives. So there are at least a 100 if not more strikers that need to be replaced. The LCAs can hardly even make up for the mig-21s that need to be replaced, numberwise.
It is not a myth that the IAF is short of combat aircafts. It is true. If you include the 21s, you are looking at 200+ aircrafts that need to be replaced in 5 years.
Giving combat capability to a large fleet of light aircrafts that every combat pilot in the IAF knows like the back of his hand, and therefore would not need additional training or familiarization or support chain, is an extremely valuable way of providing some strike capability quickly and cheaply. It would be foolish not to go for it.
Any comparison with A10 and Hawks ?
Both are planes.