Depends on what you're thinking of. From what I understand they use ground-based radars for general airspace control. If a conflict arises, A-50s would be deployed to that particular combat zone. 8-9 airframes is enough to keep 1 in the air permanently, given a small conflict zone that could be enough. Like I said, I recall reading that they want a full 12, and the A-50U will serve alongside the A-100 for quite some time, so total numbers might be even higher then that. The real problem is their centralized deployment. EW, ELINT/SIGINT, and AEW aircraft are currently at centralized bases, and if a conflict arises in one of the MDs they would have to be detached there. It would be helpful to give these platforms over to the MDs command so that they don't have to wait on central authorization, or coordinate with GenHQ on employment of these essential force multipliers.It has a very big area to cover, though. Are those 8-9 A-50 enough for that?
Look at how long it took to get some basic EW over Georgia during the '08 war. That was the reason they gave MD commanders total control over VVS tactical assets (frontal aviation). I'm not sure how much this has helped, though Russian sources seem to think so. It would make sense (if this is working) to do the same for the force multipliers that the frontal aviation needs.
From what I understand most (if not all) of the gaps have been closed as of late 2012. A bunch of articles surfaced then about the closing of radar gaps in the Russian radar field in the Arctic and the Far East. If they're closing gaps in the Arctic, I doubt there are problems in Central Russia or southern Siberia.Alltough there are large gaps, Russia have Massive Land based Radar stations scattered around.
Do VVS need to have one or two A-50U up on mission all the time, isn't it enough to have twu A-50U on an QRA standby?
They're also deploying a second network of massive strategic radars, of the Container type. There are single jump OTH radars, with the second expected to enter service by the end of this year. Again this seems to point at relatively few problems with a basic radar coverage.
Now that there are radars who can see that space does not mean that the density of GBAD sensors is the same everywhere, or even up to a certain high standard everywhere. There are places where radar coverage is undoubtedly minimal. Also a lot of the PVO radars are mobile, like the new Nebo systems. So in periods of threat, additional air-space control assets will undoubtedly be redeployed to address the threat.