Royal Navy Type 26 Frigate

[Forest Green]

It seems that at depth, Spearfish loses speed, while Mk 48 loses endurance.

Looks like 12.5nm at 80 knots (the 14 mile figure is statute miles), but that checks out. The corresponding figure for a Russian 65-76 torpedo, which can do 50km at 50 knots, is 27,300 yards. A more complete analysis would involve looking at no-escape zones, of course.

I think they double converted. 26km converts to 14nm. Likely they took a 14nm figure, thought is was miles and converted it to nm again. A Type 65 is several times the size (10,000lb vs 4,000lb), so not directly comparable.

Interestingly, the crossover point between the two settings for Spearfish is 45 knots. Above that speed, the low-speed setting gives a longer engagement range; above it, the high-speed setting. The existence of such an extreme high-speed setting implies that the Royal Navy was concerned about targets (i.e. submarines) moving very quickly indeed. For the Mark 48, the corresponding speed is 21 knots.

On a slightly more absurd note, if you can get a 30 degree up angle on a Spearfish and broach the surface, it might reach an altitude of 70 feet or so. That's high enough to offer a theoretical anti-helicopter capability. Totally impractical, of course. But amusing to think about.

I guess that would stop the commander having to get out on deck with a MANPADS like on The Wolf's Call.

 

[GK Dundas]

One could imagine adjustments to the menu to reduce noise.

You get rid of baked beans and you'll face the very real possibility of mutiny..

 

[Forest Green]

Keep them and sonar operators will keep picking up spurious Morse code transmissions.

 

[Scott Kenny]

Thanks, everyone!

On a slightly more absurd note, if you can get a 30 degree up angle on a Spearfish and broach the surface, it might reach an altitude of 70 feet or so. That's high enough to offer a theoretical anti-helicopter capability. Totally impractical, of course. But amusing to think about.

The Torpedo Museum at Keyport, WA has a great picture of a torpedo that had decided that the hovering helicopter was a good target and is coming out of the water about double the torpedo's length. It's been long enough now since I've been there that I don't remember if that was a Mk46 or a Mk48.

 

[Scott Kenny]

If you believe the Mk 48 needs to be inside 5,400 yards to kill a SEAWOLF - and that implies some rather implausible performance - then a Spearfish can do it at 10,000 yards. Or 24,000 yards if you believe the 80 knots/60,000 miles figure. Spearfish is good, but it's not that good.

Rumors say ~45knots and very quick acceleration to that speed. 57khp and a propulsor that basically doesn't cavitate so you don't lose any of that hp to bubles.