Lots of posts, so let me respond one at a time
vina wrote:I though the torpedoes carried on the decks of ships these days is a LWT and not HWT , which seem to be carried more by subs.
4 x Project 15B - 2 x 2 533 mm HWT L&T ITTL launchers amidships
3 x Type 15A - 2 x 2 533 mm HWT L&T ITTL launchers amidships
3 x Type 17 - Fitted for but not with 2 x 2 533 mm HWT L&T ITTL launchers amidships
3 x Type 1135.6 Batch 2 - 2 x 2 533 mm HWT L&T ITTL launchers amidships
3 x Type 1135.6 Batch 1 - 2 x 2 533 mm HWT Russian DTA-53-11356 launchers amidships
3 x Type 15 - 1 x 5 533 mm HWT Russian launchers amidships
5 x Type 61M - 1 x 5 533 mm HWT Russian launchers amidships
4 x Type 28 - 2 x 2 533 mm HWT L&T ITTL launchers amidships
4 x Type 1241PE - 2 x 2 533 mm HWT Russian launchers amidships
Presently SET-65KE torpedoes are used that would shortly be replaced by Varunastra.
vina wrote:The days of firing a HWT out to 30 nm range from a surface ship is gone I would think and that is where the rocket topped with a LWT comes in handy, reaches the target much faster than a HWT fired from a ship would.
A ship's ASW fire control system cues the torpedo that after launch aligns itself towards the submarine and when within range, activates its own sonar.
A ship's ASW fire control system feeds missile INS with coordinates. Before splashdown, the missile activates air brakes and parachutes the torpedo in the water. The torpedo circles in a scan pattern until it detects the submarine as shown below
No 3 refers to the air brake
The advantage of a ship launched HWT torpedo is that its cued right from launch unlike missile torpedo that has to undertake circular scan to acquire target submarine as shown above.
So I would conclude that within 20-30 km range, HWT is better. For longer ranges, helicopter launched LWT or ASW missile is better, provided cueing is available.