[Bubblehead1980]

I have had some questions on night surface attacks in the TMO update. From the README, which I apparently left out of the revised upload of my mod . This explains the new ability to pull of realistic night surface attacks in TMO 2.5 thanks to darker nights and tweaking of sensors. Took a lot of testing and modification to get the proper balance to pull off these attacks, something SH 4 has lacked since it came out. Now, they are a reality and one of the biggest thrills in the game, especially in 1944 when get inside the screen of the larger convoys and attack from within.



Night Surface Attack Information and Tactics in TMO 2.5 Update
By: Bubblehead1980


This is just a quick but in depth readme on something completely new to SH 4, the ability to pull off realistic, historically accurate night surface attacks.

For many years a major issue with SH 4 and all mods(as a result of the inherent issue in SH 4) was the inability to pull this off. For one, the night time on open ocean was just far too light out in general.
Not being able to do this was a real disservice to the simulation as it essentially prohibited a tactic that by end of war was the preferred method of attack by US submarines, particularly due Japanese shipping avoiding open oceans and transiting coastal areas.

Issues were:

Due to unrealistically light nights, enemy would often spot player if came within 4000 yards of them at night, forcing player to fire from unrealistic ranges and negating standard equipment in later war such as MK 18 torpedo, with its short range of 4000 yards.

Even if player was able to get in, fire, and attack, when they turned away they were typically shot to hell by gunfire by both escorts AND merchants. This was not reflective of the fact that a submarine is a very difficult target to not only spot, but to accurately shoot on the surface, especially at night from anything but point blank range, and even then. Very few subs were actually hit by gunfire when conducting these attacks during the war and they were, it was usually a lucky shot. Think the Bergall in December 1944. Below is a link to an excellent account of the legendary action.




This obviously prevented player from getting to realistic range and attack from outside the convoy and absolutely stopped attacks from inside convoys, which some US skippers such as O Kane in the Tang, Ramage in Parche etc. pulled off.


So, when I returned to SH 4 last year during the pandemic and decided to do this update for TMO 2.5, this was one of my major goals and happy to say I accomplished it for most part, within parameters of the sim.


Lets go over some tactical considerations when opting for this type of attack in the TMO update:


A major factor to consider is the light in the sky, the moon in particular. With the darker nights mod, some nights are dark, some nights are lighter than others. When deciding to attack, play must consider the moonlight as the AI visual sensors are affected by light. Attack before moonrise if possible, attack after (if it does, depends on area of course) the moon sets. If no moon or very little, even better. Always attack with the moon in front of you where you submarine is not silhouetted by by the light

Fog is another factor. Get your weather report before attack, if there is a light or moderate fog, you have some major help, but can still pull things off without fog.

Cloud cover helps as well. Even a light bit of cloud cover affects the light.

Phosphorescence. Of course in the sim this has to do with moonlight but check your subs bow and stern wake to see if its glowing and conduct accordingly.

Sea state. Are the seas calm? Light or choppy? Heavy seas means you will not possess the speed or maneuverability on the surface would normally , plus tough to shoot shallow draft escorts with torpedoes in down throat shots in heavy seas, if in that situation.

Your own visibility. Your targets are nearly always going to be easier for you to spot than them spot you. How well can you see them via binoculars, TBT?

Study the enemy's movements, the escorts patterns of patrolling etc for opportunities to move in and attack.. By time this method of attack becomes a common tactic , you have the PPI scope, huge help. Of course if play with map contacts on, can utilize them as well.

Majority of convoys zig on a regular basis in TMO, keep that in mind.

Consider the size of convoy, spacing between ships, type of escorts
that are closest and likely to come after you after attack. Can you outrun them? Example you can NOT out run a Destroyer or most Destroyer escorts like a Chidori/Otori/Matsu, but sub can outrun most of the ASW escorts the Japanese have, especially when put engines on overload, like the Type A, B, C, D.

Your own speed. One of the parameters by which the enemy's visual sensors detects player submarine is its(player sub) speed. Sometimes you just have to say eff it and speed up but trying to keep speed as low as possible helps.

Your angle on the bow/profile to the escorts line of sight. Another parameter the visual sensors operate on is if you are showing your broadsides to them versus your bow, stern, or quarter. I have found enemy ships do not tend to detect as easily if approaching from behind, makes sense as people usually look where they are going, not where have been and AI seems to reflect this in some ways. Something to keep in mind when working inside a convoy.

Skill level of escort matters. I have been as close as 1700 yards to an escort (with a Veteran skill level) on surface on a calm, clear, night and not detected, but I kept my profile low. I try to keep it at 2000 yards minimum though.


Quick and true story for those unaware. The USS Tang in June 1944 off Nagasaki attacked a large convoy sailing the coast (shallow waters) in Kosiki Straits headng for Nagsaki. Convoy was 8 ships with 12 escorts forming two rings around convoy. Tang tried repeatedly to make a traditional approach and shot but every time was unable due to the heavy screen, so the approached from the rear, falling in behind an escort and in front of one(closest to the one was behind) and matched speed course, surmising people inherently look where they are going, not where they have been.

This convoy had radar but did not detect Tang or if it did, likely assumed it was one of the escorts . Japanese did not have the PPI display. Tang slowly folded out of the screening vessels and got in close to attack and sink ships in one of the great attacks of the war.Tang raced away being chased and fired upon while having no waters could dive it.


These type of attacks are now possible in TMO. In fact, I added the convoy Tang attacked to the campaign, it can be attacked at historical date, time, and location and using same tactics as Tang, can attack convoy in same manner, slipping inside the screen, attacking, and getting out. I have done it. Of course, a lot of factors such as moonlight, weather etc as explained come into play.

Another factor is are you detecting radar emissions from convoy on your RWR? Radar detection in TMO update is similar to visual in some ways. Your profile to the radar beam and range matters. Smaller profile and great range, less likely they will detect you. Larger profile, shorter range, you are more likely to be picked up. Use caution, if enemy has you and is firing, they are using radar to find the range and shoot, they will likely hit you at some point.

These are factors, that you as the Captain should consider.

Given Japanese convoy composition for a large part of war, night surface attacks, well the approach, was relatively easy as they had one, maybe two escorts and the sides of convoys were not well protected, sans the occasional sweep by the lead or stern escort.


Later in war they have more escorts and their front, rear, and flanks are usually guarded fairly well and moving inside the screen may be necessary to get a shot, especially the most valuable targets such as tanker which tend to be in the center columns(When designing the convoys, attempting to make it so such as vessels were in the center columns and thus protected)



So you have attacked, ships are exploding , escorts rushing in, other merchants are nearby shooting at you. Star shells in air, you may be illuminated by a searchlight. What do you do? First is do not panic. You should have had an exit strategy in mind , go with it, adapt accordingly. Use you speed and low visibility to your advantage, especially inside a convoy. The dark of night is a great asset, just open the range and they will lose sight of you, keep moving. Keep a lookout, watch your radar, make sure you don't get trapped. If your after torpedoes are available, have them set as shallow as possible, prepare to do a down the throat shot if needed. MK 18's are great for this if they are available.


Unless have no options, don't try to fight it out with guns on surface in most cases you will be destroyed, but it is possible to do so and survive if in a tight enough spot, at night anyways. In a previous campaign, I had the USS Baya in 1945 in Gulf of Siam. Had a convoy operating in extreme shallows so had to attack on surface at night. As I was proceeding to deeper waters with a escort on my tail at 4000 yards firing, one one of his colleagues moved to cut me off, I could not turn was it would slow my speed, present a wider angle to shoot at, plus another enemy merchant was blocking both paths if I went to port or starboard. I needed to get to deeper waters so could dive if needed. I could not dive as had just 45 ft under keel. I was busting through the waves at 21 knots but was
nearly trapped. I ordered the 5 inch 25 caliber, 40 MM aft and forward and 20 aft deck manned. The radar equipped escort in front of me, blocked my way detected me so turned slight to give him a 0 AOB. He opened fire but with my low profile, and speed, his rounds missed while my five inch gun and forward 40 MM opened up at 3000 yards scored some hits, a small fire started forward and the forward gun ceased firing at us, but the AA guns continued. With tube 1 reloaded, fired a MK 14 down the throat at the escort. We were essentially playing chicken with a Type D escort. Escort spotted torpedo and moved then turned back into my sub, we turned to keep the 0 angle.At about 500 yards he turned to port again, while 5 inch, 20 mm and 40 mm guns were blazing and we passed alongside him at point blank range, perhaps 10 yards, firing at him. The escort had quit firing by this time, as we were too lose or the guns were disabled,crews dead. The aft 20 mm hit the depth charges launchers and racks setting off explosions. Also noticed looking back, the escort was listing to port, likely from the 5 inch gun hits aimed at waterline. As we passed, had two crewman wounded by gunfire and minor damage from the escorts AA guns, but we were clear. This escort (like all in TMO was set to veteran or elite). The escort astern continued to close and fired, a couple shells landed within 20 yards of the submarine. Had the aft 40 MM fire some rounds at him but eventually were able to open range and maintain lead until he turned back to tend to the convoy.

This situation was somewhat similar to one USS Salmon faced in October 1944. Salmon was severely depth charged by four Type D escorts after attacking a large tanker. The sub was a wreck and with no choice, surfaced and manned guns to make a run for it., under fire. Salmon closed an escort and came along side at extremely close range, enemy vessel would not depress its guns that low. Salmon raked the bridge and topside with 20 MM and .50 machine gun fire. The entire bridge crew of the Japanese escort was killed. Salmon then managed to escape into a rain squall.


Again, surface engagement is huge risk should not be undertaken unless in a situation like I was in the Baya or the real life Salmon was as described, even at night but sometimes have no choice but and now in the TMO Update, sub do have some real life advantages (darker nights, all guns available to fire on ships) they had which with some luck and skill, might save your boat. Now, this is at night. Daytime is still pretty much suicide.


Something I plan to do in the future is implementing night surface training into the sea trials for Balao class(which I plan to add to TMO as right now we only have Gato) and as a patrol objective for boats before departing on patrol as many did.

I hope this explanation helped, good luck, and good hunting.