The VA-111 is designed for a specific purpose to carry a nuclear warhead to the centre of a carrier group and detonate, it doesnt need to make contact with any hull or even be near by to cause huge effect.
The Skhval (VA-111) is a very impressive weapon and until recently the only one of its type in the world, the Chinese have copied it as have the Iranians and the Germans also tried it out.
While the Torpedo is extremely fast giving a submarine or a ship little to no chance of evasive manoeuvres it does have a drawback a big one, it has limited range and it is a big weapon.
Now bear in mind this is 1970's technology the range of the first generation Skhval which is a straight running torpedo and cannot be direct once launched it has a range of only 5-6nm and a nuclear blast of 20kt would affect the firing submarine yet a conventional warhead if it was to far away from target would do little.
Skhval 2 the more up to date version which came about in the mid 1990's offers up a guidance system with a vectored thrust possibility as yet not confirmed this means it does have some guidance system on board which may explain its wieght increase from 2.6tons to just over 3tons.
Skhval 2 also has a better range but still not anywhere near a conventional torpedo like the MK48 or Stingray although its speed is still there, the range of the Skhval 2 is estimated by the west to be between 12 and 15nm.
less advanced versions are for sale on the open market hence why China and Iran have shown interest.
The nose cone is movable and creates a bubble of gas in which the torpedo flies through thus it has been stated that it does have a guidance system in place, plus its seen to have movable fins too.
The back end also lends to speculation that it is in fact guided, look at the 5 o clock position there is what looks like a multi pin socket for wire guidance which again leads us to review that this could be steerable.
To be honest the technology is not mature enough i dont think to be of real value it is a show weapon the reality is the conventional torpedoes like the MK48's have much longer legs plus they are coupled with a very very good sensor systems for data collection and analysis the chances of getting the Russian boat close enough to fire one of these at a western submarine is slim.
however against an unsuspecting CVBG in some where like the Persian Gulf this would be extremely effective especially if nuclear tipped or sent by a conventional submarine sitting on the bottom in a littoral area (and yes project 636 Kilo can fire these).