Cuties... What am I doing wrong?

[Vaux]

I just recently started playing around with Mk 27 Cuties. On my last patrol, I loaded out with a couple just to give them a try, and I sank a lone Fubuki destroyer with them. It was dusk, the seas were heavy, and the DD was only making 7 knots. I took the shot from periscope depth with engines stopped and the crew at Silent Running while in visual contact with the DD at about 1,800 yards. He started going for the bottom after the first hit, so the second one was an unnecessary hit. So, I'm thinking, these things are pretty cool!

I've read a couple of posts here on the Cuties and also did some Wiki research on them. I've seen several mentions on here of other skippers firing them at depths well in excess of PD.

Well, next patrol, and I'm assigned to do a photo recon of a harbor on the Southern tip of Japan (whose name escapes me right now). I arrive near the mouth of the inlet just as the sun is coming up. The weather is "perfect", meaning it's the worst possible conditions to try to shoot up the inlet during the day... Wind, overcast, and precipitation all zero. So I decide to dive deep, go to All Stop, and wait for sundown.

Fast forward to about 1400 and my sonar man reports a contact, moving slow, closing, at long range.... and then another contact.... and another... then a fast-mover closing... and another fast mover... then a couple more slows.... Well, my curiosity was officially piqued, so I decide to go to Silent Running with screws rotating at below 25 RPM, and go to periscope depth.

I'm looking at a large convoy of 7 merchants in 3 columns - a mix of Akita, Buzyun, and Zinbo Marus - and 5 assorted DDs, moving starboard to port from my perspective. I couldn't be in a more perfect position if I'd planned it. I was planning on staying down for at least another 10 hours anyway, so I decide to go for it.

Dipping my scope, plotting courses, and noting speeds, I predict that the lead ship in the center column, a Zinbu, will pass my bow at about 1,800 yards, the lead ship in the closest column, an Akita, will pass my bow at about 1, 400 yards and slightly behind the Zinbu, and the Mitzuki DD on the convoy's left flank will pass my stern at about 1,000 yards about the same time the Akita passes my bow.

My plan is to shoot 3 mark 14s at the Zinbu then, about 5 seconds later, shoot 3 at the Akita, then down scope and head for 400 feet still at Silent Running and low RPMs. As I approach 150 feet, I'll fire the 2 Cuties I have in the stern tubes at the DD. Well, when I get to the last part of my plan and try to fire the Cuties, I get a message stating "Unable to compute firing solution" and the Cutie wouldn't fire.

What gives? Is it because I'm using Auto Targeting? If so, is there a way to over ride that on the fly?

[Dread Knot]

Originally Posted by Vaux

What gives? Is it because I'm using Auto Targeting? If so, is there a way to over ride that on the fly?

It cold be that you lost your firing solution due to time elapsed.

It could also be that the tube doors will simply close at a certain depth.

[Vaux]

I know the tube doors were open, because I heard them close after I passed 150 feet. I attempted to fire them before reaching 150. Should I have locked onto the DD with the Cuties selected to get a firing solution? I never locked on the DD, so maybe that's what I did wrong? Since they're homing, I just kind of assumed that I could just let them swim out and lock onto the first sound contact and didn't necessarily have to have a firing solution like with a Mark 14. Bad assumption?

[merc4ulfate]

The fish still need a setting to fire.

If your scope is forward and you try to fire aft it wont work.

If you had never used the lock at all you would have been fine. All you would have needed was to put the scope to your firing bearing and let it rip. From my experience, once you touched the lock it messes this up. If you use the lock at all then you need to lock onto that DD. Once you do it will hold but the DD will move.

Now if you have submerged you should be able to go to the scope and turn it slightly or adjust an offset angle on the fish. If it is not to far away the cuties should hear him anyway and I try to set mine at the shallowest depth and if I feel that the target is even shallower I will use the magnetic detonator so even if it passes below the hull it will go off.

[Vaux]

Merc,

My scope was near 0 degrees when I submerged, so that sounds feasible. I'm going to smack myself in the forehead if all I had to do was turn my scope towards my stern.

ETA: I'm also not sure I ever had the Cuties selected when I swept my scope over the DD. That may have contributed to the "no solution" issue.

[merc4ulfate]

What I do is even with the scope down if you have your attack map you turn the scope to a bearing and check the attack map. The map will show where the fish will run towards. Then I either turn the scope some more or simply turn the boat to put the tract where I want it. Sometimes I have hit crash dive and I will already be in a turn so I have the doors open already and as soon as I get close to the bearing I am firing at I will let lose.

I will even do this for other torpedoes knowing if the escorts see them they will turn to avoid and give me a few more seconds to escape for myself. Sometimes I get a few kills over that.