The Enemy Below 1950

[fitzpatv]

With eight scenarios still to go in my Standalone series, I felt the need to try something different. As submarine warfare is the aspect of CMO I struggle the most with, I took a look at The Silent Service.

This one is set in the Korean War, at the time of the initial Communist drive on Busan. Washington suspects that the Soviets are supplying the North Koreans with war material and sends the sub Segundo to investigate. Orders are to attack if such cargo is discovered, but only to engage warships in self-defence. You have support from Privateer flying boats which supply updates and it is necessary to be at periscope depth or above at specified times to receive this data, which is a nice touch.

As Segundo is essentially a WW2-era Balao-class boat, she is better-off cruising on the surface, using radar to search, as the scenario makes clear at the outset. I started cautiously at periscope depth and headed W to intersect the likely routes from ports in the Soviet Far East to the notified harbours in North Korean-held territory. Before long, I had a message that three Soviet destroyers and four MVs had left Posyet, heading to Sokcho. It was clear that I'd have to surface and move at Full speed to have any chance of an intercept, so I did so. A drawback to this is that movement on the surface above Cruise speed drains your electric batteries.

After a while, I had a surface contact ahead. Suspected a patrolling North Korean MTB. These lack sonar and are only a threat if they catch you on the surface, but there I was. Dove and spent some time investigating/trying to steer around the contact - only for it to turn-out to be a harmless junk.

Not long after this, I received a second message, giving a position fix for the convoy. It was further E than I'd expected and I had to reverse course to rendezvous with it. It was also moving more slowly than expected at 14 knots, which helped offset this.

Having moved to a likely intercept point, I was beginning to doubt my judgement when I picked up the convoy to the NNW. Dove and stalked it at periscope depth. I was nicely positioned for the MVs to sail into my torpedo arc, but there was a destroyer ahead of the MV column and others left and right of the second transport. If I continued as I was, the left-hand one would go right over my position and detect me, even with her 2nm range active sonar.

Decided it was best to back-off, then manoeuvre around the escorts to intercept the less-well-guarded third and fourth MVs. This entailed a trailing shot and margins were obviously going to be tight, but the alternative seemed suicidal.

Matters weren't helped at all by being blind when moving at Full speed, so that I had to keep slowing to Cruise to get position fixes. In the event, I failed by the barest of margins to get in range of the last MV. I did, at least, get confirmation that they were carrying military supplies. I could probably get it to work if I replayed it enough from the Save I took before attacking, but I lack the patience.

Worse, someone must have seen my periscope wake as, despite my having been well out of their sonar range AND in their baffles, the three escorts were homing in on me. Getting away was not easy. I tried warding them off with single torpedo shots, which caused them all to turn away, but they could outrun the tinfish every time - even when I let one get within 1.64nm and it was moving toward me at 4 knots. Despite these evasive manoeuvres, they were able to immediately resume contact upon turning around, even out of sonar range and with Segundo moving at Cruise or Creep. They responded to every course and speed change I made. In the end, I dove as deep as possible and then altered course away at Creep.

This worked, but upon rising to periscope depth, the relentless escorts were still just a matter of 7nm away. Thankfully, they were heading away from me and I escaped by steering at Creep in the opposite direction.

There was now no chance of catching the convoy, so I ran down the clock, steering in the right general direction. Before too long, I got a message saying that the convoy had reached port. With each surviving MV scoring 25 points against me, this counted as a Disaster.

Quite an absorbing game in some ways, but:

1. The escorts were too efficient and too relentless. Incidentally, had there been a second US sub, the three of them abandoning the convoy to hunt me like that would have had dire consequences for them. They also attack before the Segundo has done more than look at the convoy, which is excessive.

2. The player should get credit for identifying the military cargo. Doing this and escaping should probably count as a Draw, if not a Minor Victory (especially as even intercepting the convoy isn't easy). It would also make more plausible sense in a historical context, as the US was hardly likely to start a war with the USSR over something like this. Sinking one MV is hard enough, but the victory conditions suggest that you need at least two and maybe three. In short, too hard.

[Rory Noonan]

Great AAR!

The Silent Service scenarios are much more difficult than most other DLC or standalone scenarios; however they're all designed to have high replay value as each run will be slightly different due to randomisation of various elements like weather (and therefore sonar conditions), starting positions etc. In the case of this particular scenario, the origin and destination ports are randomised, as is the route the convoy takes. The parameters for randomisation mean that unless you do something really silly you will be able to make it, but it will require some thought and a somewhat unique approach on every playthrough.

[fitzpatv]

Good to hear about the flexible scenario design, as the replayability is welcome. There's at least a hint of more potential surprises in this scenario, with both the title and the briefing suggesting that Soviet subs are a possibility.

While I maintain that the victory conditions are too hard, it's still a good game if played for its own sake without worrying too much about the result. I'm also pleased to have the save file for the attack, as I can re-run it as a training exercise whenever I like.

Not surprised that Silent Service is harder than the general run of CMO content, as running subs is the toughest feature of the game. When enemy ASW choppers get involved, it's usually suicide without air support and I daresay some of the other scenarios feature this problem in abundance.

[fitzpatv]

A couple more observations. Just played the attack again from the save file, trying out advice from the Silent Service section of the forum.

Going in below the layer, as suggested, has the drawback that you need to identify the military cargo before attacking, so it's necessary to stooge around at periscope depth until you've done this. Once again, a destroyer detected my periscope beyond its sonar range when I was moving at Creep - their ability to do this is phenomenal. It really doesn't matter that 1950s sonar is rubbish, they don't need it!!. Thankfully (or not), I was able to get the intel before diving.

I found that diving below the layer is great for avoiding detection, but has the big minus that you can't fire torpedoes at a sonar contact, due to 'cross-range ambiguity' restrictions. Further experimentation at just above the layer and shallow revealed the same problem at those depths. When I went to periscope depth, the problem was removed, but a destroyer was directly on top of me (once they've detected you once, they stick to you like glue, regardless).

I fired a total of eight torpedoes at a freighter at 40% chances to hit, scoring just two hits, which failed to sink her (what prayer have you got of sinking more than one ship?).

The destroyer clobbered me with her first depth charge and rocket attack. It has to be said that depth charge attacks in WW2 were nowhere near this accurate (the database gives an individual depth charge a 10% chance to hit, which is too high).

Might have had more luck with Mk35 torpedoes due to their re-attack ability, but I didn't have them loaded at the time of the save and the situation didn't allow me the luxury of changing this.

[.Sirius]

Hi
I'll amend the depth charge % to 1%

[fitzpatv]

Thanks for that. Good to see this kind of responsiveness from developers (especially as a retired IT tester!)!.

[fitzpatv]

As a footnote, I converted the Segundo's attack (above) to a scenario for a WW2 naval boardgame I designed myself some years ago. This already includes scenarios for most of the significant engagements of the conflict and is usually pretty true to history (it produced close to the real-life result for the Battle off Samar, Leyte Gulf, for instance).

Things actually went very similarly to the way they did in CMO. Segundo lined-up an attack on the leading merchantman, but was very unlucky and missed six times with her bow tubes on 40% chances (she would have needed several hits or a 1 in 10 critical for a kill, but damaged ships lose way and fall astern). She was then detected by sonar and, diving, survived a depth-charging by two of the escorts. The detonations broke the sonar contact and, with the freighters accelerating out of range, Segundo turned to flee. Razyashchyy managed to regain contact, but the sub again survived (kill chances were 5% per salvo). With the escorts moving left, right or straight ahead at slow speed according to dice rolls, Segundo eventually made good her escape.

I only allow ships to spot periscopes at a range of 1nm or less and then only on a 5% chance.

My victory conditions were:

- Segundo sunk = Soviet Victory
- At least one MV sunk and Segundo escapes = American Victory
- Anything else = Draw.