H4 questions i always wanted answers to

[kcdusk]

Das Boot?

 

Doesnt that start with 70 odds minutes of "nothing happening"? True to life, maybe. Best film though?

[CV32]

Das Boot? Doesnt that start with 70 odds minutes of "nothing happening"? True to life, maybe. Best film though?

 

Absolutely, because that truly captures what one could expect from life aboard a submarine. Best sub film of all time, imho.

[TonyE]

Das Boot for sure imho. Enhanced by the primary spoken language being German

[kcdusk]

U-571 anyone? An updated das boot? (jon bon jovi?)

[CV32]

U-571 anyone? ... (jon bon jovi?)

 

Afraid U-571 doesn't do it for me. I expect a Hollywood movie to take some liberties with facts and storyline to create a workable piece of 'entertainment', but this one probably goes a little too far in that respect. Again, just imho.

[TonyE]

Afraid U-571 doesn't do it for me. I expect a Hollywood movie to take some liberties with facts and storyline to create a workable piece of 'entertainment', but this one probably goes a little too far in that respect. Again, just imho.

 

Brad and I just have the same opinion on just about everything, including U-571 <_>

[broncepulido]

I can't say what's my favorite submarine film (in general, for me, the war movies are bad movies), and I remember my grandfather was submariner (sunked in C-3 by a torpedo fired by U-34).

But some unknown mad Spaniard had presented a truckload of submarine films someplace in the Net (in spanish), and I can now refresh memories with some titles, some of them unknown to me previously, other famous films, other apparently infamous films, and of course I've not see all of them, but this is a relation of some of those films (I shown also for your fun the "imaginative", "asimetrical" or "diversive" spanish movie titles)(And some other information about this topic in http://en.wikipedia.org/wiki/Submarine_films ):

http://en.wikipedia.org/wiki/The_Enemy_Below (Duelo en el Atlántico).

http://www.answers.com/topic/depth-charge-2008-action-film (Amenaza en las Profundidades).

http://en.wikipedia.org/wiki/USS_Seahawk Film title Submarine Seahawk, Spencer G. Bennet 1958 (El Halcón Marino).

http://en.wikipedia.org/wiki/Operation_Petticoat (Operación Pacífico) a famous and good film with acceptable historical basis.

http://en.wikipedia.org/wiki/Destination_Tokyo (Destino Tokio)

http://en.wikipedia.org/wiki/Deep_Shock (Impacto Profundo) Unknown to me, sci-fi.

http://en.wikipedia.org/wiki/Above_Us_the_Waves_(film) (Operación Tirpitz), 1955, unknown to me, perhaps interesting.

http://en.wikipedia.org/wiki/Hostile_Waters_(film) (Aguas Turbulentas), I suppose based in the book.

http://en.wikipedia.org/wiki/Murphy's_War (La Guerra de Murphy), curious film, but I dont like it very much.

http://en.wikipedia.org/wiki/Shock_Waves (La Isla de los Nazis Submarinos, !!!???), awful apparence.

http://en.wikipedia.org/wiki/Gung_Ho!_(1943_film) (Gung Ho!)

http://en.wikipedia.org/wiki/Hell_and_High_Water_(film) (El Diablo de las Aguas Turbias), curious script and curious film.

http://en.wikipedia.org/wiki/The_Bedford_Incident (Estado de Alarma) a realistic and must-to-see film, improved with the years pass, the role played by Widmark is as my boss (something as a district attorney) in the real life, and I hope the end of our relation will not the same as in the film !!!

http://en.wikipedia.org/wiki/Up_Periscope (Infierno Bajo las Aguas).

http://en.wikipedia.org/wiki/Operation_Pacific (La Flota Silenciosa).

http://en.wikipedia.org/wiki/On_the_Beach_(1959_film) (La Hora Final), not exactly a war movie, but a good film.

http://en.wikipedia.org/wiki/Das_letzte_U-Boot (Das Boot 2, La Última Misión), first images, a SS Foxtrot, playing as U-234 !! later, I see is a East German director, TV movie 1992.

http://en.wikipedia.org/wiki/49th_Parallel_(film) (Los Invasores), curious script, only very marginally submarine film.

http://en.wikipedia.org/wiki/Torpedo_Run (El Último Torpedo).

http://en.wikipedia.org/wiki/They_Were_Expendable (No Eran Imprescindibles), but I see it's a PT Boats movie !!

http://en.wikipedia.org/wiki/In_Which_We_Serve (Sangre, Sudor y Lágrimas).

http://en.wikipedia.org/wiki/Crash_Dive (Tiburones de Acero).

http://de.wikipedia.org/wiki/U_47_%E2%80%9...nleutnant_Prien (No Spanish title), german film in german.

http://en.wikipedia.org/wiki/Gray_Lady_Down (Alerta Roja Neptuno Hundido), not a very good film, but some interesting items, as DSRV-1.

http://en.wikipedia.org/wiki/Assault_on_a_Queen (Asalto al Queen Mary) obviously not a war film.

http://www.answers.com/topic/blockade-film-1 (Bloqueo) it seems a leftist propaganda film.

http://en.wikipedia.org/wiki/Enigma_(2001_film) (Enigma) good film and good script.

http://en.wikipedia.org/wiki/The_Russians_...ians_Are_Coming ( ¡ Qué Vienen los Rusos !), great and sensible comedy.

http://en.wikipedia.org/wiki/Submarine_Attack (La Gran Esperanza/El Último Submarino) unknow to me.

http://www.answers.com/topic/submarine-x-1 (Submarino X-1), with James Caan, unknown to me, but the title is self-explanatory.

http://en.wikipedia.org/wiki/In_Enemy_Hands_(film) (U-Boat), US-German acceptable minor film.

http://en.wikipedia.org/wiki/Torpedo_Bay (Mientras Dure la Tempestad), curious franco-italian film, about Betasom (one of his alternate titles).

http://www.imdb.com/title/tt0345967/ Submarines (USS Majesty Alerta Nuclear).

http://en.wikipedia.org/wiki/The_Hunley (The Hunley) It sembles a good historical reconstruction film.

 

And reading about this topic, I think this film

http://en.wikipedia.org/wiki/Morgenrot_(film)

http://www.imdb.com/title/tt0024352/plotsummary

is the movie that my grandparents saw when my grandfather said to my grandmother that if he was trapped in a sunken submarine and saw that the oxygen was finishing him, he would shoot his own head.

[kcdusk]

Electromagnetic Support Measures (ESM) pick up radar and radio (from 4.3).

 

1. So does this mean a submarine with ESM can detect radars? Even if submerged?

2. Can ESM (on ships and planes) pick up sonars?

3. I thought a submarine using 'Active sonar" were easier to detect than a "passive" sonar. But looking at the sonar range modifiers on page 4-11 i cannot see any penalties for using active. What am i missing?

4. ESM picks up radio transmissions (4.3 again). Does this mean the enemy can hear your radio traffic? Or just knows theres radio activity?

5. Does a submarine need to be on the surface to use its radar?

[CV32]

Electromagnetic Support Measures (ESM) pick up radar and radio (from 4.3).

1. So does this mean a submarine with ESM can detect radars? Even if submerged?

 

Yes. If the ESM mast is raised.

 

2. Can ESM (on ships and planes) pick up sonars?

 

No, not in the traditional sense of ESM. (See Acoustic Intercept Receivers and all that).

 

3. I thought a submarine using 'Active sonar" were easier to detect than a "passive" sonar. But looking at the sonar range modifiers on page 4-11 i cannot see any penalties for using active. What am i missing?

 

The biggest penalty for using active sonar is that (like radar) it can be detected well beyond its effective range. See 4.4.5.1.4. for example.

 

4. ESM picks up radio transmissions (4.3 again). Does this mean the enemy can hear your radio traffic? Or just knows theres radio activity?

 

In real life, it can mean that the enemy can hear your radio traffic, if his gear is sophisticated enough and yours isn't. This isn't covered by Harpoon 4 rules.

 

5. Does a submarine need to be on the surface to use its radar?

 

Although the radar is mounted on a mast as well, I think in practise (especially in peacetime) a submarine is most often surfaced before using the radar (principally for surface navigation).

[kcdusk]

4.4.5.1.4 Sonar Transmissions - thats the rule i was after. Active sonars are rated as "loud" targets. Funny how you can read the rules over and over, some of it sticks, some of it you know you've read but just cant find it and other parts you read but cant remember any of the details.

 

I always wondered why submarines "ran" after torpedoing a ship in a convoy. It seemed to me that running at high speed gave off noise that ASW ships would chase. I thought as a submarine captain i would go deep and reduce speed to 0kts and just hang there silently and let the searching ships move away from me as they widend their search. Then i could crawl away at slow speed in the opposite direction.

 

I've almost finished gaming a scenario where a submarine was being searched for by two ASW ships. The ASW ships are using active sonars, and the speed of my submarine (0kts) is not making a difference to the chances of being found because sub speed does not influence active sonar detection. Being below the layer halves the range. But while the sub stayed motionless the ASW ships got within active sonar range and detected it. Now flushed out, the sub is running. Was staying still a good tactic or not? Hard to say. If the ASW ships started moving away from the sub then staying still might have been valid. Thoughts?

[pmaidhof]

Funny how you can read the rules over and over, some of it sticks, some of it you know you've read but just cant find it and other parts you read but cant remember any of the details.

 

Yes, happen to me more than I'd like to admit Or there are situations where the answer is mockingly right in front of me and I cannot "find" it.

 

Thoughts?

 

I'll have to take a look and hopefully respond later.

[CV32]

I've almost finished gaming a scenario where a submarine was being searched for by two ASW ships. The ASW ships are using active sonars, and the speed of my submarine (0kts) is not making a difference to the chances of being found because sub speed does not influence active sonar detection. Being below the layer halves the range. But while the sub stayed motionless the ASW ships got within active sonar range and detected it. Now flushed out, the sub is running. Was staying still a good tactic or not? Hard to say. If the ASW ships started moving away from the sub then staying still might have been valid. Thoughts?

 

Staying still is not a great tactic versus active sonar. I say that very generally, however, since it really depends on a lot of other variables. Sitting on the bottom in relatively shallow water would probably work well because the active sonar will get plenty of echoes and might have a difficult time distinguishing a submarine from the ocean floor. Also, sitting directly underneath an actively pinging sonobuoy apparently has some merits. (How you maneuver yourself into such a position without first giving away your presence, however, escapes me).

 

If it were me, and my mission had been accomplished (i.e. targets sunk, or the risk of continuing engagement was too high), I'd be looking for every opportunity to creep away rather than sit still.

 

I should add that I am thinking especially in the context of a non-nuclear submarine. Nuke subs can pretty match speeds with any ASW surface ship, so in open ocean you should be able to clear datum in a hurry.

[kcdusk]

I had a submarine hunt down a convoy of 3 large merchant vessels being protected by 4 Krivaks and 2 patrol boats (the vessels were determined by random rolls. Your thinking whats the point of patrol boats, they dont carry sonar? Well the sub might have fired torpedoes at them, making their presence known and likely given their position away).

 

The submarine approached and starting trying to identify targets. It detected some contacts (failed to detect a few while others were still out of range) and then started the process of identifying the exact nature of each of them. One of the ROE was that the sub couldn't fire until it knew the class of ship it was firing on.

 

The process of having a contact and identifying it 100% while maintaining all the older contacts so the sub had a true picture of the situation was frustrating. Contacts were in either the 50% or 75% range, add the 15% for maintaining a contact takes the chances to 65 and 90%. Then you normally need to maintain the contact for a few turns until your able to positively identify it (all while not loosing the contact). There were 3 merchant ships and 6 other boats so there were 9 ships in the convoy and despite good odds there were so many contacts to manage some kept dropping off the sonar before being regained and starting the process of identification again.

 

After slipping by 2 Krivaks the submarine eventually identified a merchant ship and fired 2 torpedoes. One hit, causing some damage but massive critical hits. 2 Krivaks were close by and closed on the submarine. The submarine dropped below the layer and held its position rather than flee the scene. Active sonars found the submarine and the Krivaks closed in. The submarine figured he was found and headed away from the convoy at maximum speed, before stopping, turning around 180 and quietly heading back towards the convoy hoping to give the 2 Krivaks the impression he was bugging out before quielty tiptoeing past them again.

 

The 2 Krivaks caught up to the submarine. When the sub turned around to head back to the convoy one Krivak lost contact. The other Krivak was closer and maintained contact, achieved a good TMA before launching its ASW Mortar (first time for me using ASW rules and mortars in particular, not sure if I got it all correct. See post below for a list of points).

 

The Krivak continued to send depth charges over the side from its ASW mortar while the other Krivak kept a distance away trying to re-establish contact and join the fight if necessary.

 

At the moment the submarine has a Krivak directly overhead dropping DC's and another Krivak still trying to locate it. Its only a matter of time before the DCs do some hurt to the submarine. The Krivaks have a higher speed that the submarine so outrunning them is not an option (point noted re nuclear subs being faster than pursuing ships). The Krivaks are using active sonar so no matter how quiet the submarine is, he is being detected and the Krivaks have a 90% chance of maintaining contact. So its not looking good for the submarine at all.

 

It might be time for the submarine to load a torpedo tube with a human manikin, some oil, broken chair and a life jacket and make it look like a critical hit has taken place!

 

 

____________________________

 

Did you know for ASW

to make a depth charge attack you need a "Good" TMA per 6.4.3.3.

the ship needs to pass directly over the submarine

if dropping DCs into shallow and intermeadiate I depth zones the ship must be moving at a speed greater than 15kts or risk damage from the DCs

only one ship may attack without risking damage to a second ship from the first ships DC's

 

 

 

______________________________

 

Some other quick thoughts on H4.1. Note i was using 3 minute turns;

Plotting was quick and easy

Movement was quick and easy

Planned fire was quick and easy

Detection was ..... very time consuming. Only 4 ships (Krivaks) had any means (sonar) to detect the submarine. The submarine could detect each of the 9 ships. So that was 13 different "detections" that could take place. As ranges and speeds changed so did detection possibilities. Even if the chance of detection didnt change, you had to do the maths in order to check that despite changes to speed and distance there was no change in detection possibilities. And for each detection gained (or lost) you have to keep track of how long the detection has been maintained (or lost) because that influences things like TMA, chance of maintaining detection and classifiing a target type. I was very glad when the game boiled down to 2 x Krivaks and the submarine.

[Warhorse64]

At the moment the submarine has a Krivak directly overhead dropping DC's and another Krivak still trying to locate it. Its only a matter of time before the DCs do some hurt to the submarine. The Krivaks have a higher speed that the submarine so outrunning them is not an option (point noted re nuclear subs being faster than pursuing ships). The Krivaks are using active sonar so no matter how quiet the submarine is, he is being detected and the Krivaks have a 90% chance of maintaining contact. So its not looking good for the submarine at all.

 

It might be time for the submarine to load a torpedo tube with a human manikin, some oil, broken chair and a life jacket and make it look like a critical hit has taken place!

 

 

Put a torp into the Krivak? Even if it doesn't hit, it may provide enough distraction to break contact.

[kcdusk]

If a submarine is moving along at a depth of 125m, and it moves into an area of ocean where the depth of water changes from 200m to 75m, does the submarine crash? Or would the game umpire rule the sonar detects the change in depths and inform the captain of the need to change depths so he could plot new movement?

 

Seperate question, do rules for submarine nets or mines (floating or chained to the ocean floor) appear in any modules?