The Invisible Enemy [Archive]

Franconicus

02-16-2011, 16:56

Chapter 1 – autumn 1941

A small tanker convoy is sailing northwards along the western coast of Africa. It is escorted by the 36 Escort Group, consisting of two sloops and seven corvettes. On deck of the Bittern-class sloop Stork stand the leader of the convoy, 45 years old Frederic John Walker. Although he watches the sea, the convoy is outside of the usual hunting grounds of the German submarines and out of the range of the German air force. And so his thoughts begin to wander and he starts to reflect his career.

He served in the Royal Navy since 1914. Twenty-seven long years! When the Second World War began, in 1939, his career seemed at dead end. Still a Commander, he had been ignored for promotion to captain and indeed had been scheduled for early retirement. He gained a reprieve, however, due to the commencement of war and in 1940 was appointed as Operations Staff Officer to Vice-Admiral Sir Bertram Ramsay. Even so, he still had not been given a command, despite expertise in anti-submarine warfare that would no doubt be indispensable in the Battle of the Atlantic. During the Dunkirk evacuations he was Mentioned in Despatches for his work during the evacuation.

Walker finally received a command in October 1941, taking control of the 36th Escort Group, based in Liverpool, home of Western Approaches Command. The group is used to escort convoys to and from Gibraltar. So far, the duty has been uneventful.

During the wars, Walker was trained as an expert in Anti-Submarine Warfare. He studied the ability and tactics of the German submarines. Unlike others, he was not taken by surprise when the German boats attacked the British supply routes very effectively in 1939. The British did everything to improve the defense. The introduced the convoy system, did everything to increase the number and range of the escorts, they built bases on Iceland, which was then handed to the USA. American ships began to escort convoys in the Northern Atlantic and it was only a question of time when the US would enter the war completely. During the first six months the escorts have been able to push back the submarines, and the casualties decreased.

However, Walker knows that the battle is not won. The Germans have a huge program to build new submarines and soon their number will increase tremendously. From their bases at France they will be able to send their ships into the wideness of the Atlantic Ocean. Britain can only win the fight, if the escorts manage not only to push back the submarines, but to sink them.

Walker looks northwards. Behind the horizon there is Gibraltar, the destination of this convoy. The Germans are sending submarines in the Mediterranean Sea and those are passing Gibraltar. The escort will have to be alert when they near Gibraltar. But they still have time and Walker is determined to use this time to train the escort group.

Chapter 2 – 1. December

A commander of the Royal Navy stands on top of the Rock of Gibraltar and watches the clouds drifting across the sky. There must be bad weather over the Bay if Biscay, but here at Gibraltar it is still warm and dry.
Walker’s convoy finally reached its destination. The rest of the journey was uneventful. Although he should feel glad about it, Johnny Walker is in a bad mood. He still could not show his skills. Yes, he is hungry for a fight, although he knows that his mission is to protect the merchant ships, not to sink hostile ships. The men of his group were drilled during the trip and every man knows how to do his job. He knows that he can rely on them. But can he rely on himself? There are still many tactical issues, he should have changed. Although he is decided to use a more aggressive tactic against the enemy, his perception is rather vague. And he knows that he must have a clear plan before he goes into battle, a plan that every member of his group is drilled for. First of all, he must decide about the formation of the escort group. Maybe there should be different formations for day- and nighttime. During night, the ring has o be much tighter. But then, what has to be done, if a submarine is spotted? How many ships should chase it and which ones? What should be the orders for the remaining ships, which have to secure the convoy then? How long should the ships chase a submarine before they had to return? What should happen, if no submarine is spotted, bit an own ship is sunk? He has to discuss this with the commanders of the other ships. There has to be a decision right now, because he wants to use the time at Gibraltar to train his group, before the next mission begins.
Down there, Walker can see that the harbor is almost filled. Some of the ships came with him; they are waiting for the next convoy to sail to England. Others came from the Mediterranean Sea. Comrades report, that German submarines make this ocean a dangerous place, too. The wardroom is filed with stories and rumors. An officer told him stories about the hard fight in Africa; about the superiority of the German tanks and about a wonder gun, which grenades penetrates every British tank with high precision, even at an incredible distance. Yesterday, news came up that German tank divisions took Moscow. Stalin committed suicide and Russia is about to capitulate. Many officers were very pessimistic, how Britain could continue the war under such circumstances. Others expressed their hopes that this could make Roosevelt change his mind. They were sure that America would now join Britain. Roosevelt would most likely settle his differences with Japan and declare war on Germany.
Walker shakes his head. He decides to go to the commander’s office. There he hopes to get reliable news. But the commander of the base knows little about Russia or America, but he can give some information about the current situation in the Atlantic. Walker learns that the Germans have at least three boats at the western exit of the Med.. Walker was lucky that he passed them unseen. The commander also tells him about latest news from the Western Approaches Command.
“I know that we had high casualties, Walker, but I can tell you there is something going in the old Royal Navy. You will soon have better weapons. Like these new ash can throwers. I heard that they do not influence the ASDIC signal. Or the new RDF, which works similar as the ASDIC, but on the surface. You will be able to see the enemy even at night.”
“Well, have you seen these so-called RDF?”
“Sure! Some of our Swordfishes got one.”
“And, does it work!”
“Yes! Now we detect German submarines almost every day.”
Walker sighs: “I wished I had the new equipment, but if wished even more to lead a convoy through more dangerous waters.”
The commander of the base laughs: “Do not say this too loud. The German might want to make you wish come true. Oh, by the way, I almost forgot to tell you that I received a message from the WAC. We will soon send another convoy to Liverpool. I guess it will be a rather large one and the 36 Escort Group will guard it. The route goes along the coast of France, through the operation fields of the German submarines and bombers. Are these waters dangerous enough?”
“When do we set sails?”
“Do not hurry. You will have to wait for more ships. You will not set sail before mid of December. And once you are at Liverpool, you may also get the RDF and ash can throwers.”
“Oh, I really wished I had them now!”
“Do not worry, Walker, I have something brand-new for you, another innovation, almost as good as the RDF. It is called “snowflake”. A new kind of flare that turns night into day. With that you can chase submarines even at night.”
“How many can you give me?”
“I have enough to equip your ships as well as the merchant ships.”
“Do you have any details about the enemy?”
“Well, Walker, as I already told you, the enemy has some boats right out there. They will detect you soon enough. If you manage to pass them unseen, you come into the range of the German bombers. They will find you. Then you will cross the marching routes of the complete German submarine fleet. Maybe you will even meet some heavy cruisers or battle ships. I bet you will have your fun.”
“Will I get air support?”
“I have air patrols out there and they will keep an eye on you as long as you are in range. Then you will be all alone, until you reach the coast of England.”

Franconicus

02-16-2011, 16:59

I posted the first two chapters again. There is nothing new, but all should have the same information. Hopefully I get the next chap this week, then you will have options to discuss.

I am still trying to find an enemy for you. I found some, but they are all German sailors older than 85 years and it takes some time to convince them. However, most of them are from Prien's crew, which raided the English port of Scapa Flow - so I think they are the right opponents for you!

King Kurt

02-16-2011, 17:51

Good news Franc - to have some experienced people on the other side is fantastic - especially as they are older than me!! I am used to being the senior here!! I am a spritely 58 on friday -

Franconicus

02-18-2011, 10:39

Chapter 3 – 11. December

Johnny Walker uses the time to exercise. New tactical maneuvers are trained again and again as well as communication and the usage of the new snowflake flares, which really turn night into day. Walker is satisfied; his group is ready to face the Krauts. He only wishes he had some air cover.
His men are glad when the group finally returns into the harbor of Gibraltar. They hope for some recreation before they will set sails again.
Walker goes straight to the office of the commander of the base. He finds him with another RN officer.
“Ah, Walker, come in! I already wanted to call you back. I have new orders for you. Your convoy is complete, 32 merchant ships in total. You will decamp on December 14th. And I have news for you, good news and bad news.”
“Start with the bad news.”
“We received the information that the Germans forming a new wolf pack to intercept you. So be careful.”
“And the good news?”
“Do you know Commander Mac Kendrick, Walker? He is commander of the escort carrier HMS Audacity.”
“Yes, I am, and I am also commanding her three escort destroyers, Blanckney, Stanley and Exmoor. Western Approaches Command told me to protect this England bound convoy.”
Walker looks skeptically at Mac Kendrick, who has the same rank as he, but a higher age of service.
“I am glad to have you with me. The convoy can surely use some air support.”
The base commander smiles at Walker: “Well, Commander, now you have a notable force. The Krauts should better watch out for you.”

Two hours later Walker sits together at a briefing. Along with him are the captains of the escort ships as well as Commodore Fitzmaurice from the Spero, who is the commander of the merchant ships.
Walker opens the briefing: “Gentlemen, you all know the target of our mission. We have to sail to Liverpool without any casualties. However, there are German submarines and bombers on the way, trying to intercept us. We have 13 warships and about 32 merchant ships. I suggest that the merchant form 9 columns, the escort vessels will be placed around. We will sail with 7.3 kn. Thanks to the Audacity we will have a continuous air shield. I am sure that Commander Mac Kendrick’s planes will keep the Germans on distance.”
Mac Kendrick pipes up: “Wait a moment, Commander Walker. You should know that the Audacity has currently four airplanes, exactly speaking four Grumman Martlets of the No. 802 Squadron FAA. These are not enough to patrol all the time. We should only use them when we are attacked!”
This news frustrates Walker, but four planes are better than none: “Alright, we will have to discuss if the planes could do at least some patrols. I think we form the convoy the usual way, in the middle there will be the biggest ships and the ships with the most valuable cargo. Of course, the Audacity will be in the centre, so she is well protected and I can use her destroyers to chase submarines.”
Mac Kendrick shakes his head: “Walker, I am sure, you are an excellent naval officer, but it seems as if you know nothing about airplanes. It is always difficult and dangerous to start and land on a ship. The pilots as well as my crew are all well trained and still it is risky. You have to keep many things in mind, especially the wind. Escort carriers sailing within the convoy have a too limited maneuvering space which is required to turn the carrier into the wind to operate aircraft. It is absolutely necessary to operate outside the convoy. Operating in the area near the convoy gives me all the space I need to turn as required for aircraft operations. However it is plane to see the necessity of a special escort for the carrier alone. Therefore the Western Approach Command gave me three escort destroyers.”
Walker sighs silently. Things turn out to be much more difficult as he thought they might be: “Well, Mac Kendrick, I have to think about it. I will give my orders later. I think we can end our meeting today. I want everybody to get their ships ready. Err, and one thing to the merchant ships. I expect high discipline from everyone. You have to keep your place in the convoy, you will keep the rule of communication. You will get snowflakes, which enables you to light the night. However, you are only allowed to use them with my permission and you have to report every contact with a submarine to the next escort vessel.”
This time it is Fitzmaurice, who answers back: “That is rubbish. Most of the merchant ships are equipped with guns. If we see a submarine between our ships, we can effectively fight it. We can even ram it. It would be foolish to ask each time we have a contact and wait for an answer. We should use the lights to mark the submarine and then fire at it from all sides. Your escort vessels won’t help much, once a submarine is between our ships.”
Walker shakes his head. He had always had the feeling as if he had to guide flock of sheep through a pack of wolves, but know it seems to him as if the sheep may cause more trouble than the wolves.

A) Decide how to the use the planes.
B) Decide where to place the Audacity, where to place the escort verssels and how to use them (drawing might be useful=)
C) Give orders to the merchants.
D) Decide the course.

By the way, happy birthday, Kurt. Hope you feel young enough for this naval battle!

Fisherking

02-19-2011, 08:09

When do you want us to reply?

Franconicus

02-20-2011, 19:19

March 1st!

King Kurt

02-24-2011, 13:48

First - thanks for the birthday greetings - a naval IH was the perfect present!!

Now - to business. We have 4 planes and they are fighters, so their main purpose is to attack aircraft - most likely Fw Condors. They have a range of about 850 miles and a top speed of about 330mph - so they can probably comfortably operate for about 3 hours. So I would propose 2 hour patrols with the first plane taking off at dawn and then one an hour until dusk when all planes would land. It is December so we only have about 10 hours of daylight to worry about. Most planes would fly twice and 1 three times. A plane would have 2 hours to be refueled and armed. This patern will give us 2 aircraft in the air most of the time, enough to react to any threat.Where possible planes would be spotted ready for take off should there be a problem. Patrol area should be around the convoy - up to 50 miles to the front, 40 miles to the side and 20 miles to the rear. Planes should fly at 3 to 5,000 feet as sighting subs is the top priority. They will be armed with their guns and flare/ smoke bombs on their hard points. If a sub is sighted its position will be reported and then it will be attacked with guns, prefereably from the rear as the sub's guns are on the fore deck. The idea is to drive the sub underwater to slow it down. Once it dives, its last postion will be marked by the smoke float so the convoy's escorts will be well placed to attack it. The other task is to detect and attack patrol planes - Fw Condors - when one is detected, it will be attacked.

I think this will make best use of our limited air asset. As for the carrier, I am inclined to put it close to the rear of the convoy and assign one destroyer as a close escort, leaving the other 2 to reinforce our convoy escort.

Orders for the merchants? - leave the fighting to us and keep convoy discipline. Perhaps we could asign a junior officer to each lead ship per convoy line to cordinate the ships in his group.

Finally - course - I think as proposed before - feingt south west, then north west to keep out of sight of spanish observers before heading for England - I assume Liverpool Franc

Well that is my proposal - what do you all think??

Franconicus

02-24-2011, 19:14

By the way, your opponents finally begin to form. As I told you, they are a bunch of German Uboot veterans. Could be very interesting, but we would need some more allies to play.

King Kurt

02-24-2011, 20:36

Small change to the plans above - cut down patrol areas to 30 miles in front, 20 miles to sides and rear. Also the escort should be split into an inner ring - close to the convoy and an outer ring - about 10 miles away - then the U boats will have to fight through 2 layers. we will attack them at every opportunity - maximun aggression. Also I would suggest the convoy has 5 columns - for a more compact box. Finally, when plane detects a sub, it will come up to a suitable height so it can be detected by radar so the sub's position is registered.

ELITEofWARMANGINGERYBREADMEN88

02-26-2011, 01:52

Franconicus

02-28-2011, 19:31

Could someone make a sketch of the convoy with the places and names of the escorts?

K.K.: What radar?

King Kurt

03-02-2011, 14:02

Could someone make a sketch of the convoy with the places and names of the escorts?

that would stretch my PC ability!!! - perhaps somebody else could help??
K.K.: What radar?
Some of the larger escorts have radar and the Audacity has simple air warning radar. I picked up this as a tactic by reading an account of the battle online - so they must have been able to do it!!

Franconicus

03-04-2011, 17:18

Chapter 4 – 14. December

Finally it is time to set sails. The Escort Group leaves fist, then the merchants and finally the Audacity with her escort destroyer. After a short but rough dispute Walker gave Mac Kendrick the order to provide air patrols all day through. Mac Kendrick replied that this would certainly lead to fatigue and therefore would reduce the combat strength in case of an attack, but Walker insisted. So the planes will patrol an area of about 30 miles in front and 20 miles to the rear and sides. The escorts would form an inner and an outer ring with a maximum distance of ten miles. The merchants will form a box with 5 columns. The Audacity will be in the center of the last row, with a destroyer as her personal guard. The speed of the convoy is 7.3kn.

The convoy sails course South West until it is out of sight from the Spanish mainland and then turn North West to sail to Liverpool.
This evening, another convoy will leave Gibraltar, a small Capetown bound one.

In the darkness of the night Walker’s convoy enters the Atlantic Ocean. Walker has the strong feeling that the fighting will soon begin. At 23:30 he hears the sound of depth charges and sees the light of phoscars on starboard. A swordfish of the Gibraltar patrol found a submarine with the A.S.V. and threw three charges. The distance is about three nautical miles on the right.

1) Please draw a sketch of your convoy with the positions and names of the escorts.
2) What are your commands regarding the sub?
3) Please give orders regarding your course! Drawing may help!!

Deadline is March 16!

P.S.: Your enemy consists of 6 to seven high mitivated players!!

King Kurt

03-09-2011, 13:18

I will get on to it Franc - been a bit tied up the last few days. A few comrades would help!!!

Kagemusha

03-09-2011, 19:28

Im here to join the team. Can someone brief me what an earth is going on?

Here is a map.I can start updating concerning movements of the bloody krauts and our own forces.Lets go sub hunting!

https://img405.imageshack.us/img405/9849/atlanticnorth1803.th.jpg (https://img405.imageshack.us/i/atlanticnorth1803.jpg/)

Strike For The South

03-09-2011, 19:33

Reporting for duty

King Kurt

03-10-2011, 17:44

Franconicus

03-10-2011, 19:27

I have done a diagram but have no way of putting it on the forum. Franc can I email it to you? - I have your email for some time ago.

And welcome to my old friend Kage and Strike for the South - we may be few, but we are select!! Time to sink some U boats.

Kage - to get some background, just look over the old Allied thread - fischerking and myself did quite a lot of background.

Sure!

Here is a map.I can start updating concerning movements of the bloody krauts and our own forces.Lets go sub hunting!

Wow, Kage, you actually found the Atlantic Ocean.

Kagemusha

03-10-2011, 21:55

Sure!

Wow, Kage, you actually found the Atlantic Ocean.

Well i am by no means an expert in naval warfare, or not even a novice. Based on what i have read. Is our job at tactical level to decide convoy escort strenghts, formations and schedules or something at strategical level?

King Kurt

03-11-2011, 14:07

Franc - diagram sent to your email - hope it arrives OK!!

Franconicus

03-12-2011, 10:49

https://img849.imageshack.us/img849/2104/77266608.th.jpg

http://www.megaupload.com/?d=MU7UUGUY

http://www.megaupload.com/?d=MU7UUGUY

Franconicus

03-14-2011, 15:14

Please do not forget the deadline!!!

Just a very short summary: You (aka Johnny Walker) are the leader of an escort group, which guides a rather big convoy from Gibraltar to Liverpool. You have support of the carrier Audacity with two destroyers. However, the commander has the same rank as you and he does not agree wih your strategy.
You just left Gib. Intel reports that there are subs in front of you. You already decided, that the planes from the carrier (there are only few) should patrol around the convoy during daylight.
You are still in range of the Gibraltar air patrols and it seems as if one of these planes detected a sub on your left.

Now you have to decide:
- the formation
- how to react regarding the sub
- your course!

Kagemusha

03-16-2011, 17:33

Gah! Where are Kurt and Fisherking? My humble opinion is that we will continue sailing towards Liverpool, keeping the convoy inside of the protective rings. I dont want to start running after a single sub leaving the convoy.

Franconicus

03-16-2011, 17:44

Kurt is drowned in the bath and Fisherking sold his honor to the Krauts, I guess.

Fisherking

03-16-2011, 18:57

Dispatch the escorts from the left flank to deal with the sub and contact patrol air-command and drop some depth charges on the sucker and some markers. He has to escape to the right or go into shallow water and be had.

We have to continue on the south by south west course for a couple more days.

Convoy zigzag away and resume course.

Escorts know their drill. Locate and destroy. One ship guides the other onto target.

Franconicus

03-16-2011, 19:34

So one vote for staying at the convoy, one for hunting.

Fisherking

03-16-2011, 19:41

If the sub is in range of the convoy it should be hunted.

If it is beyond line of sight and air cover has chased it under then we leave it and continue on course.

As you didn’t give a range then we have to consider the possibilities. At any rate we are still headed south on this leg, are we not?

King Kurt

03-16-2011, 20:55

I have posted my thoughts direct to Franc - but basically attack with escorts - we can't use the Martlets as it is night.

ELITEofWARMANGINGERYBREADMEN88

03-17-2011, 16:36

I say lets go hunting!!

Napoleon The Emperor Of Europe

03-21-2011, 10:18

Yo.

Franconicus

03-21-2011, 17:31

Chapter 5 – 15. December

Walker hesitates a moment, but then he realizes the threat that hides there about three nautical miles on the right. If there is really a submarine, it located the convoy and will soon call the other submarines. There is no alternative, this submarine has to found and eliminated or the convoy will soon get into troubled waters.
The Stork, the destroyer Exmoor and the corvette Convulvulus turn right and hurry to reach the place where the Swodfish dropped its bombs. In the meantime the convoy turns southwest, to get away from the submarine.
Now the search begins. Walker’s Stork is front runner then slows down to listen while other ships approach on either side. In his mind Walker marks a circle around the assumed position of the submarine. The three ships are ploughing the waters with their ASDICs inside this circle. All the time the men have the strange feeling that the submarine is watching them, maybe just adjusting the launching tubes to send them to the deepness.
The search inside the circle takes almost an hour, but there is no contact. Walker feels pain in the stomach, maybe because of something the ate, maybe because he knows that the escort of the convoy is weak and the submarine could attack, right now, while he was wasting his time on the search. On the other hand, it could still be here. If so, he has to find it. He sends signals to the other ships and soon all three lay silently, just watching and listening. Maybe the commander of the submarine things that the search is over and comes to the surface. Then he will get a bad surprise. However, he could also try to attack the British ships, which are perfect targets now. Nothing happens at all. And maybe this is the worst thing for the nerves of the British sailors. Finally, Walker decides to give up the search and to return to the convoy. At four o’clock in the morning he arrives. Fortunately, everything is alright. The three escort ships take their positions. The convoy still sails course southwest, now leaving grid square CG97 and entering DJ21. Behind the ships the sun rises. Everything is quiet and peacefully. Maybe this damned Swordfish had had a false signal and there hadn’t been any submarine at all. If not, the waters around him will soon swarm with German submarines. Soon he will leave the area of the Gibraltar air patrols, and then he can only rely on himself.
Walker thinks about the course to Liverpool. The usual one would be westwards, until the middle of grid square CF, and then straight north to sail west of Ireland. The usual one. The convoy would be quite far away from the occupied coast of France, where the Germans have their bases. The course is still within the range of the German planes, but they would not have much time to cruise there. There are two drawbacks, though. First, the course is longer and therefore the submarines would have more chances to attack. Second, the course is well known to the Germans as well.
Walker is wondering about another course, closer to the Spanish coast, closer to the bases of the Germans. If the convoy would sail right between CF and CG, the journey would be significantly shorter. However, a risky plan!
And there is still a third option. He could stay on course southwest for a while. If his German attender sends this course to the other German boats, they may wait for the convoy further south. Then, when Walker changes to course to north, they may be far away and maybe loose the contact. And there is still the other convoy behind them, which destination is Freetown.

Which is the right course:

A) Take the usual one. It is a good compromise of distance to the German bases and length of the journey.
B) Take the short way home. It is closer to the German bases, but we will be sooner at home and the submarines may have less chances to attack.
C) Stay on the southwestern course for a while. Maybe this misleads the Germans.

P.S.: Welcome Napoleon!

Fisherking

03-21-2011, 19:25

C Stick it out for another day before turning West Northwest for a while, then take the Northern course.

King Kurt

03-21-2011, 20:51

Definately C and change course as night falls - quite early as it is December

ELITEofWARMANGINGERYBREADMEN88

03-21-2011, 22:59

C,I Agree.

Kagemusha

03-26-2011, 16:21

C it is.

Franconicus

04-08-2011, 18:11

Chapter 6 – night of 15./16. December

The ships are still constantly running southwest along the coast of Morocco. This is the normal route to Freetown and every mile brings them further away from their destination Liverpool. Hopefully this is suitable to mislead the Germans, because it certainly makes the journey longer and gives the Germans more time for attacks.
The convoy now sails in grid square DJ18.This means that it left the air cover provided by the Gibraltar squad and is now left on his own. All day long the planes of the Audacity encircle the convoy. The only connection home left is the radio. Western approaches command shows that it still cares for the lonely convoy and send three messages:
1) There is another convoy about 40 nautical miles behind. It is bound for Freetown.
2) There are about six submarines close to the convoy.
3) There is a storm in the Atlantic, but the convoy should have at least another day with rather good weather.
Night falls, Walker alerts the crews of the escort ships. He knows that the Germans are out there, even if he cannot see them. However, nothing happens. At midnight, the convoy is right in the middle of grid square DJ18. If it goes on for another day, it will pass the Canaries. Sooner or later Walker will have to change the course to west or northwest. The three escort destroyers Blanckney, Stanley and Exmoor are the fastest ships of the escort and very useful for hunting submarines. However, these three ships have only a very limited range and will have to return to Gibraltar on December 18 or 19. Maybe just when the German submarines are starting to attack. Walker still wonders about the right course when the radio operator receives a distress call. It comes from the “Empire Barracuda”, which is obviously attacked by a submarine. Looking at the coordinates, Walker sees that it must be a ship from the Freetown bound convoy. Poor boys!
It looks as if the peaceful period of the journey is over. This may be the signal for opening the battle!

Tasks:
1) Decide about the course.
2) Any measure against the submarines?

Fisherking

04-09-2011, 11:34

The convoy should zigzag at five minute intervals. Sub commanders have to observe, target, and fire. It takes time to do the trig once the course is plotted and run times for torpedoes is typically about 2 minutes. Frequent changes of 45°-60° would make targeting of the ships difficult. If submarine contact is made then the convoy should make a 90° turn away from the contact as directed by the escort commander and make course changes every two minutes while contact is ongoing.

An example:
/
\
/
|
\
/
\

We should make a turn to the west at once and continue for about 12 hours. then turn North West for 24 hours before settling on our homeward course.

Franconicus

04-09-2011, 13:36

I am not an expert on this, but it seems hard to change the course of a big ship every two minutes. Even harder to change the course of more than 30!

Fisherking

04-09-2011, 13:55

The ship may take a little time for the ship to respond and to settle on course but it is a matter of changing the wheel the number of degrees to bring about the settings.

If you think it is too frequent we can double the times but it dose diminish the effect.

King Kurt

04-09-2011, 19:25

I think 2 minutes is too quick, especialy with an ungainly convoy. I think every 20 -30 minures is more in keeping.

Fisherking

04-10-2011, 06:47

The idea is to make it difficult to target the ships. 5 to 10 minutes may do that but 20 to 30 minutes is a very minor inconvenience at best.

In that amount of time a Skipper could set up complex shots, targeting 5 ships, launch all his torpedoes, and be almost reloaded before we changed course to foul any shots.

While 2 minutes is difficult, it is only while the convoy is under attack. If you think it is too frequent leave it at 5 minutes and 10 when not under attack.

It is stressful on the helmsmen but not so stressful as being sunk. We want the convoy to have a plan of action so that the ships don’t panic. It is as much a morale factor for us as it is a deterrent to the Germans.

It also means that the subs have to close to a much closer range to get a good shot which also means we have a better chance to detect and kill them.

To get a good shot the U-boat might even want to surface and risk a couple of quick launches before diving and running away. That puts him in our sights and even the gun crews on the merchant ships might get in some shots.

The frequent changes keep helmsmen alert and under attack it keeps there minds off worrying about being hit. Otherwise they will be watching the water for wakes or imagined wakes and zigzagging on their own, which dose not keep the convoy together.

King Kurt

04-11-2011, 13:01

Fischer

While your comments would be true for individual ships, we must remember that the convoy is made up of lines of the order of at least 5 ships long. Each line would be about a 1km long. The turn would be about a single piont, so the rear ships would have to travel to the turn point before turning. At 12 kts that would take at least 3 to 4 minutes. Moreover the ships do not turn on a sixpence, so the act of turning would take some time. Also, at night, such rapid maneavers would lead to collisions.
I found this on another forum
"The Zig-Zag patterns used by Allied convoys were VERY strict and difficult navigational evolutions... in fact, the Navy sailors used to joke about worrying MORE about getting run over by a freighter than hit by a torpedo.

Each Ships Captain would receive a plan with a series of "Zig-Zag Plans"... so once underway, the Convoy Commodore could order by flashing light a specific "plan" based on a base-course. For example: "Zig-Zag Plan 10, 110* " would mean a base course of 110 degrees, with a 15 degree turn to port after 20 minutes, a 20 degree turn to starboard after 30 minutes, a 25 degree turn to port 15 minutes later, and then a 10 degree turn to starboard after 25 minutes... REPEAT"

One of the KEY problems with the Convoys, is that they moved at little more than 10 knots (11.5 mph), and more often at 6 knots !! A German submarine could move on the surface at almost 18 kts (20 mph)... twice as fast as the convoy.

SO, the Zigzag was used to confuse the fire-solution of the U-Boat... a steady course is EASY to determine when to shoot, it's like leading with a shotgun. IF the target(s) are making random (but coordinated) course changes it either throws the solution out the window, OR forces the sub to approach closer. THIS makes the sub more susceptible to detection and counter-attack.

The freighters move in a "tight" group, zigzagging, while the ASW escorts (Corvettes, Destroyers and Frigates) roam about like boarder collies. The submarine plots it's fire-solution by basic navigation skills, and since this in the days prior to computers, a well-timed "ZAG" can negate the weapons officer's computations.

Zig-Zag navigation went out the window pretty quickly in World War II as a result of:

Faster cargo ships
More escort ships
Better equipped escort ships with ASDIC (sonar) and Radar
Escort Carriers (subs HATE airplanes !!)
British cracking the German codes - NOW you just AVOID the subs."

So it may be possible that our convoy might not even ZigZag at all. However, assuming it does, the abovesuggests that the periods are 10 to 25 minutes and random. also, I believe we would be unlikely to zigzag during the night - there was too much of a risk of collisions.

Franconicus

04-12-2011, 18:03

Deadline on Sunday, that's alright?

King Kurt

04-12-2011, 20:05

Deadline on Sunday, that's alright?

OK with me. I am with Fischer re the the course - the subs are north of us so we need to go west first, before heading NW. The 3 escorts who will have to leave we will put between the convoy and the subs - i.e. to our rear/ right hand side of the convoy. Finally we should head for the storm - bad weather is our friend.

Fisherking

04-13-2011, 07:51

I think we are in agreement for the most part.

We can use a longer zigzag.

However, I was not thinking of columns making turns but individual ships maintains approximate stations but turning. If only the leading ships turn it defeats the purpose of the zigzag. Then it is only a course change. They are still ducks in a row to be hit by aimed torpedoes. If each ship turns at a precise time on a precise course it is another matter.

The convoy is arranged in a box formation so that it reduces chances for collusion, keeps structure and cohesion, and need not reshuffle position. The Convoy Commodore is not the leading ship but nearer to the center of the convoy to maintain control. The other ships should more or less wheel about him.

If you think of the formation as marching men the zigzags are not column movements but flanking movements, or half flank in this case.

If you don’t think they have enough time to practice this or that professional merchantmen are not smart enough to navigate a water ballet, we can just drop it.

Franconicus

04-13-2011, 17:48

Just one question to get you right: zigzag at daytime, night or all day long?

Fisherking

04-13-2011, 19:00

So it may be possible that our convoy might not even ZigZag at all. However, assuming it does, the abovesuggests that the periods are 10 to 25 minutes and random. also, I believe we would be unlikely to zigzag during the night - there was too much of a risk of collisions.

I guess we will go with daylight hours. But if attacked at night we had better make some sort of change.

King Kurt

04-15-2011, 12:59

Just to let you know, I am off on my hols from today, so will be offline until 26 april - don't sink too many subs while I am away!!

Franconicus

04-22-2011, 18:16

Chapter 7 – 17. December

December 17th, at 0:00 Walker gives the convoy the signal to turn west. In the darkness the ships turn away from the African coast to the wide Atlantic. Walker hopes that this maneuver will lead them away from the submarines.

At 1:30 STANLEY and SAMPHIRE report that three ships are missing, the Blairatholl, Thyra and Ocean Coast. Lt Cdr FT Renny, captain of the SAMPHIRE, asks for the permission to search for the lost ships. Walker swears like a trooper. This is a fine moment to loose contact, now that the Germans are so close. Walker hesitates. Sending escorts would weaken the protection of the rest. He could fire some flares, but that would show their position to the enemy, too. Walker still wonders what to do when he gets a new message from the SAMPHIRE that the three missing ships are returning.
At daybreak the Martlets get off for their daily duty and the convoy begins to zigzag. This slows down the cruising speed to 5 knots, however. At noon, the convoy just passes from grid square DH 3944 to 3866, Walker makes it turn northwest. The journey is still peaceful, the air patrols have nothing to report. The sky is cloudy and a fresh wind is blowing the clouds westwards.
One hour later, Walker receives bad news from the Audacity: one of the Martlets has an engine failure and it difficult to repair it on board of the carrier. Therefore, there are only three combat-ready planes left, not enough for a permanent patrol. Furthermore Mac Kendrick tells him that he is going to stop the patrols as the wind is getting too strong.
Radio messages from England report, that there are still several submarines close to the convoy and that a storm front will come in the next 24 hours.

1) Course?
2) Other orders?
Have a nice holiday! And KK: Beware of subs!

King Kurt

04-26-2011, 12:55

I have returned refreshed from my family holiday!! Despite 2 sea journeys on the Isle of Wight car ferry, we managed to avoid any wolf packs lurking in the Solent - no doubt to my superior tactics!!

so - to work. the storm will be our friend - worse news for the U boats rather than us. I suggest the following:

1) Zig zaging is slowing us down - we should cut back our course changes to say twice an hour.
2) We should steer best course for home, taking into account the lesser Zig Zag
3) We should maintain our inner and outer ring of escorts.
4) We should ground all aircraft - which sounds like it has happened already. However we should urge one patrol a day - say at dawn - if at all possible with the weather. When the weather improves, we can go back to as best air coverage as we can.
5) During the night, we should arrange a fake attack with snowflakes etc to the east of the convoy. Our destroyers who have to return to Gib are there, so it would be good to try and make use of them. All merchants will be informed of the fake attack and it must be stressed that they should not fire their snowflakes.

Any thoughts fellow sailors??

Fisherking

04-29-2011, 21:17

I too have been away due to technical problems.

Anyway, it all sounds good.

Do it.

Franconicus

05-06-2011, 17:54

Chapter 8 – Noon, 18. December

Walker continues his march through the Atlantic Ocean. The leader of the Liverpool bound convoy decides that the time for detours is over. He conveys the captains of the other ships to reduce the zigzags to two turns per hour. He also announces that the convoy will turn northwards during night to take the straight way home.
The weather is getting worse and huge seas reduce the speed of the convoy to some 6 knots, however. There is nothing Walker can do to raise the speed, but at least the Krauts will suffer the same way.
The air patrols have already been stopped and the convoy has to rely on the lookouts. But during daytime of the 17th, nothing happens. After midnight, Walker gives the signal for the three destroyers and soon Blanckney, Stanley and Exmoor sheer out of course and disappear in the night. Soon Walker can hear the sound of detonating ash cans and the shine of snowflakes. The three destroyers are doing a good job to pretend a combat and Walker hopes that his trick will work and lure the Germans away from the convoy. He waits a couple of minutes and the he gives the order to turn northwards, away from the three destroyers and hopefully also away from the enemy.
At 2:00, however, he receives a message that one of the merchants claims that he has spotted a periscope. It is the Benwood, a freight ship in the middle of the fourth column. Minutes of anxious waiting follow, but nothing happens. The merchant ships keep their nerves and stick to the orders.
At 2:42, Lt. Cdr. Sayers from the HMS Rhododendron reports a short ASDIC contact in the western forefront of the convoy. However, the contact soon disappeared.
Walker has to face the fact that the Krauts are still out there waiting for their chance to prey and that the escort is significantly weakened by the withdrawal of the destroyers and the loss of the air patrols.
Fortunately, day breaks and still all of the ships are alright. Walker receives a message from the Audacity. Mac Kendrick complains that the Audacity has lost her escort and is now without any protection.
At December 18th, 12:00, Walker marks the position on his map. It is the cross between the squares CF99, CG77, DH31 and DH32. The convoy is still marching northwards with a speed of about 6 knots. The storm is getting worse and Walker hopes that he can keeps at least the 6 knots.
1) How to rearrange the escorts now that the destroyers are gone?
2) During night, the convoy will pass a awful storm. Any orders regarding this?

King Kurt

05-09-2011, 12:41

I would suggest the following for rearranging the escorts.

1) replace the 2 destroyers from the front group with 2 corvettes - so forward group is Stork + 2 Corvettes.
2) Put a corvette on each corner of the convoy. They will patrol the flanks and rear of the convoy.
3) Put Audacity between the front of the convoy and the front group of Stork + 2 Corvettes.
4) This leaves 1 corvette which will take station at the rear of the convoy in the middle. It will lie slightly off the rear of the convoy so it can move to assist on either flank if the convoy is attacked.

As for the storm, we need to use it as much as possible without putting the ships at risk. Franc - could you give us some information on the storm and where it is in relation to the convoy and the UK. For example if the storm is coming in from the West, could we skirt round the storm leaving it to the east of us - i.e. between the convoy and the French/ Spanish coast?

Fisherking

05-09-2011, 13:19

I disagree strongly.

The strongest reaction force belongs at the rear and so does the carrier.

Let me get the number of escorts straight.

We had 9 and were reinforced with the 3 of the carrier group?

Now we lost those three and still have the 9 and the carrier?

I would recommend that we have two corvettes at the front and on the flanks.

The two destroyers and a corvette at the rear.

One of the destroyers can reinforce a group where it is needed when a sub is found, but two always need to protect the rear of the convoy.

If the escort is too weak it will invite a surface attack by the U-boats, which is far likelier to succeed than a long range submerged attack. Also at the rear the carrier is afforded better protection. She is every bit as vulnerable as a merchant ship while sailing unescorted.

If we are getting contact reports we need to steer west for a few hours to try and lose them until the storm hits.

Then it is likely we need not worry too much until it blows its self out.

Subs at periscope depth are also effected by the storm and waves. They can even be thrown to the surface.

Report the several contacts and request some reinforcements. It will take days for them to arrive but it is better to alert them now than have to wait while we are in contact and losing ships.

Franconicus

05-09-2011, 17:42

Your escort force currently consists of:

2 sloops Depthford and Stork
7 corvettes : Rhododendron, Marigold, Convolvulvus, Penstemon, Gardenia, Samphire and Vetch
1 escort carrier Audacity (Cdr MacKendrick)

In total 10 vessels.

A big storm front is coming from west to east; it already hit you, but the centre is still coming!

King Kurt

05-10-2011, 12:35

The position of the escorts depends on where you percieve the threat is most likely to come from. I would have thought that is most likely to come from the front of the convoy, not the rear. U Boats are not fast boats, even on the surface, so they would want to position themselves in our path and attack accordingly. They would have to travel significantly faster than us to come up behind us. I placed the carrier between the front screen and the front of the convoy as that position, on my deployment of escorts, would be in the maximum level of escort. I had also missed the sloop Depthford from my calculations, so that could sail as close escort to the carrier.

Also we are trying to have a 2 layer approach so the U boats have to fight through two layers. The front group are several miles in front of the convoy so they can attack any subs detected. fischer - why do you think our threat is most likely to come from the rear?

As for the storm, I would be hesitant to turn to the west - our most recent detected threat was to the west and by turning to face the storm we will be slowed even more. My inclination is to press on to the North and only turn into the storm - ie to the west if the storm gets so fierce that we need to face it head on for seakeeping reasons - ie to stop waves hitting us side on.

Fisherking

05-10-2011, 15:37

U-boats are faster than our corvettes.

They us their surface speed to position themselves for an optimum position for attack.

Directly a head is not that good of a position. It is better to be slightly to the flanks. Head on shots are very likely to miss.

However stalking and trailing the convoy is from the rear. That is where you will most likely see them surfaced. The rear flanks are also where it is easiest to get inside the convoy with a dash on the surface at night.

The Destroyers are considerably faster than the corvettes and the U-boats. Having them in the rear is the best place to reinforce on of the three groups, should they make contact with a U-boat.

Should the front group contact a sub we want to change direction for a time to avoid it anyway.

When and if we are reinforced by more escorts we will strengthen the front group first of all. But at the moment we have early enough to cover the convoy and the escort carrier is a big target. The rear is also the best location for command and control.

We can maintain this heading for a time and then try to shake them off in the storm but if the convoy is sighted the pack will spread out to form a cordon. Until we have clear weather and air cover things are going to stay a bit dicey.

King Kurt

05-12-2011, 13:05

Our U boats are slighter faster than our corvettes - about a knot according to Wiki - but they are faster than our convoy. On those grounds, I am happy to change my thoughts to those of Fischer. I think we should concentrate on the rear of the convoy and the eastern flank as they are farthest from the storm - we should keep an all round watch, but maybe place any extra boats in those areas.

Fisherking

05-12-2011, 18:36

When we get more boats we can think about that. For now we should have the teams of two front and flanks with the two destroyers and a corvette at the rear.

Franconicus

05-16-2011, 13:35

Well, you do not have any destroyers:

Your escort force currently consists of:

2 sloops Depthford and Stork
7 corvettes : Rhododendron, Marigold, Convolvulvus, Penstemon, Gardenia, Samphire and Vetch
1 escort carrier Audacity (Cdr MacKendrick)

In total 10 vessels.

A big storm front is coming from west to east; it already hit you, but the centre is still coming!

Could you please precise the position of your escort ships (front/rear, one ring/two rings ...) and their orders in case of an attack or any other event?

Fisherking

05-16-2011, 18:44

I stand corrected then, two sloops in back. :P

King Kurt

05-26-2011, 12:08

Hi guys - just to let you know I am off on my holidays again - back on the 6th of June - so no U Boat sinking until D Day!!

Franconicus

05-28-2011, 16:17

Chapter 9 – until noon, 19 of December

At 15:00 Walker sends signals to rearrange the order of the escort ships. He is willing to keep to rings to protect the convoy, even though three destroyers left the group. There is no more ship left to give the Audacity an extra protection, but the two sloops will be at the rear of the convoy and therefore close to the carrier. Walker is already looking forward for the protests of Mac Kendrick.
The escort ships have just taken their new positions, when the storm front arrives. From one minute to another the sky is getting dark and it begins to rain cats and dogs. Walker has always been thinking that ‘cats and dogs’ was a silly picture for heavy rain, but this night he changes his mind. The droplets fall as if they had the size of cats and the strong western wind drives them, so that they hit almost horizontal. But not the rain is the worst thin, neither the wind nor the darkness. All over sudden, huge waves come from port and hit the side of the Stork.
The little sloop is thrown from one side to another like a little toy. Walker has to use all his skills to get the Stork through the raging seas. He has no time to watch for the rest of the convoy or the submarines.
At the break of day the storm is gone. The sea is calm and the wind is an easy breeze. It stopped raining and the dark sky brightens.
After a stormy night in a small vessel Walker and his men feel like dead fishes, but there is still no time to rest. First of all, Walker has to get an overview of the situation.
The vessels of the 36th Escort Group report of minor damages caused by the storm: radio installations of the Rhodedendron is defect; the Marigold has a blocked 4-inch gun, and Samphire tells that ten depth charges fell overboard. The Audacity is alright.
The situation of the freight ships is more confusing. The columns dissolved and the ships are spread over an area three times as big as the original order. The fright ships did not suffer any serious damages, although Lago lost her radio installations.
Four ships are missing, the Adjutant, the Fylingdale, the Rucking, the Fagersten and the Sheaf Crown.
Walker decides to send the planes of the Audacity to search for the missing ships. It is noon, the convoy is at CF9399, when the planes return. They found a group of four ships 20 nm southeast and another ship 25 nm south.

Until now, the German boats haven’t attacked. But the situation is dangerous. The convoy is stretched so far, that it is impossible to build a dense defense with his boats. And the ships that left the convoy are easy targets.

So what is to be done?

Fisherking

05-28-2011, 17:36

I guess we will need to slow the convoy by a couple of knots and send a sloop to bring the sheep home.

The planes can spot any subs near the surface and help vector the lost ships home.

Meanwhile, it is not a total waste, the time can be used to regroup the main convoy, make repairs, and conduct a search of the area.

Let that be a lesson, also. Next time we turn to meet the storm.

Franconicus

05-30-2011, 18:13

Could you please give more precise orders. Which sloop do you want to send. Orders for the rest?

Fisherking

05-30-2011, 21:57

The 7 corvettes and the Stork will maintain station on the convoy.

The Deptford will herd the sheep. It should also use active mode for its ASDIC. It may cover some of the engine noise from the ships and give a little scare to any U-boats in the area. It will also make them easier to locate and as the ship is a way from the convoy it won’t be giving much away.

Air Patrols will be constant until the convoy is back in order and then resume the regular scheduled patrols. We need a second plane in the air for this operation.

Front team: Convulvulus & Vetch, Left flank team: Rhodedendron & Sapphire, Right flank team: Gardenia & Marigold. Walker, in the Stork and the Penstemon will maintain the trailing position until rejoined by Deptford.

Audacity will remain in the rear rank of the convoy in the company of the one CAM ship where we can keep an eye on the both of them.

We will add an extra lookout on each bridge crew and practice our zigzags until everyone is back at their stations.

The ship to the south at 25nm is in the most danger. The others are almost in visual range and my find their way here before the escort reaches them.

Once everyone is joined up we will steer a course for BE 78. Once there we will set course to AM 16 and then for home.

Is that enough detail or do you want to know the mess cooks name and what he plans for dinner?

Franconicus

06-01-2011, 18:21

The airpatrols around the convoy or the lost sheeps?

Well for dinner, it's plumpudding, I assume.

Fisherking

06-01-2011, 18:42

2 planes; One to patrol around the convoy, One to keep an eye on the lost sheep and help shepherd them home without incident.

By the way, have they fixed the fourth plane yet?

They should have a full machine shop, spare parts, and the facilities to make or repair just about anything. They only have four planes and I am sure they are carrying six spare power plants.

I wonder as to the competence of the skipper and crew.

Franconicus

06-09-2011, 09:51

Chapter 10 – noon until dusk, 19 of December

Although all of his men are tired from the stormy night, there is no time to rest. Walker gives his orders, the merchant have to take their places in the columns again, the securing ring has to be reorganized and those which lost their ways have to be gathered.

It will be the business of Lt Cdr HR White and the slop Deptford to look for those ships and to bring them home, Walker cannot spare any other escort ship, now that the convoy is spread out over the seas. But at least White will be assisted be the Martlets.

Walker feels that the defenses is spread out too far, that his convoy is very vulnerable. Lookouts are intensively staring out, but still there is no sign of any German boat. It is like fighting a phantom, Walker thinks. Maybe there is nothing out there; maybe they lost the convoy in the storm. Well maybe they just launched a torpedo to attack the Stork.

Walker changed the course of the convoy to northwest, and slowed it down, to give the missing ships an opportunity to return faster. The Martlets are already out. The southeastern formation was still on the wrong course, northwest, now they changed and will reach the convoy soon. White is already on the way. Walker worries more about the southern ships, the Sheaf Crown. It will take until dusk for her to reach the rest of the convoy.
Then the Stork receives a radio message: SSS – SSS- Rucking attacked submarines – hit by torpedo - SSS.
The Rucking is one of the ships in the southeast. Walker hurries to the radio installation. He wants to call White, but before he is able, other messages come in:
“SSS – Adjutant – attacked by submarines – burning”
“SSS – Fylingdale, … “
The last message is interrupted. The operator cannot get contact anymore. Instead there is a message from the Martlet, which operates over the combat area: “Here M1 - submarine – under surface – need reinforcement”
Walker finally reaches White, but the Lt Cdr heard the messages and is already within eyeshot. He hurries to the position, where the plane found the submarine.
In the meanwhile there is another message from the Adjutant:
“SSS – Adjutant – burning – Fylingdale sunk after torpedo attack, Rucking attacked twice and rapidly sinking - need help – urgent – SSS”

But now, HMS Deptford enters combat. The Martlet reports that the submarine is still close under water. When Deptford approaches, it is not diving deeper but just turning her bow against the English sloop. The Deptford passes the place where the submarine should be and throws a row of ash cans. The water is boiling. Deptford makes a tight turn and returns throwing cans again. When she returns she finds spill and wreckage on the surface of the sea. White reports Walker that he sunk a German submarine and that there are no survivors. As there are no other signals of German submarines, he turns to the place where the Rucking went down. The Sea is filled with wreckage and lifeboats. HMS Deptford begins to rescue the sailors, when there is a strong detonation at her heck. Ten minutes later, HMS Deptford disappears in the seas.

Half an hour later the Fagersten joins the convoy and takes her place in the column. The Adjutant radios that the fire went out and that the ships is able to run with 4 knots. At the same time, Walker receives a message from the Sheaf Crown. She is also hit by torpedoes and rapidly sinking. The captain asks for help.

Walker looks into the sinking sun. Three ships are lost, the Fylingdale, the Rucking and the Sheaf Crown. Adjutant is still behind the convoy. She is damaged and only able to run slowly. The worst news is that the Deptford is lost.

Walker shakes his head. There is no time to regret, the Adjutant needs help, there are still sailors from the sunk ships in need of rescue. Furthermore it is getting dark and the Germans may attack the convoy this night. And there is no doubt left that there are German submarines out there. And after all, Walker has to inform the headquarter about the latest events.

Before he makes decisions, he receives too new messages. One comes from the Audacity, telling him that all Merlets are ready for combat, again. The other one comes from England, telling him that there are four other submarines coming from the French coast to meet his convoy.

King Kurt

06-09-2011, 12:17

So you wait until your birthday to get the action going!!:laugh4::laugh4::laugh4:

Happy Birthday Franc - hope the heat from the candles is not too intense:birthday2::cake::cake::cake::happybirthday3::candle:

Franconicus

06-09-2011, 13:59

Thank you very much! No, not too hot. Only one freight ship was burning, the others went straight down!

King Kurt

06-10-2011, 13:01

Franc - as a year older - do you feel wiser??

As for the predicament our Capt Walker is in, I think this needs a little thought. Several lessons need to be learnt:
1) We must never assume that debris/ oil means the U Boat is sunk - it was a common ploy to eject debris and oil to make ships think they were sunk. So if we see that again, we should depth charge that area immediately and press on with the attack. More definate evidence is needed - bodies in the water, our hydrophones picking up the sound of the sub breaking up etc.
2) In hindsight, we made a mistake by sending a single corvette to bring in the stragglers. Our strategy should be to attack any subs in numbers - the hunting group concept. If stragglers occur again, we should either leave them to catch up by themselves or take the whole convoy off to pick them up.

as for the future - I will ponder it over the weekend and come up with pearls of wisdom for Monday.

Fisherking

06-10-2011, 19:38

I think he is having a little joke at our expense. :inquisitive:

I guess that skipper was a sub-lieutenant and dead drunk to boot, if he fell for a ruse like that or stopped to pick up survivors alone.

Either that or Franc had a bit too much to drink when he made the post. :laugh4:

Franconicus

06-18-2011, 08:10

Gentlemen, your move, please.

In the face of the falling night and the threat of a German attack I think it would be helpful if you make clear:

how should escorts act if they have contact to a sub?
how to proceed with sailors from sunk ships?
how to proceed with soldiers from sunk submarines?
where to place the Audacity and how to use her planes.

Deadline Monday, alright?

King Kurt

06-21-2011, 13:24

Monday looks fine - I will post my thoughts soon

King Kurt

06-24-2011, 12:26

When a sub is detected, it should be attacked with a minimum of 2 but preferably 3 escorts. This would allow 1 boat to be a looker - ie searching with sonar, possibly slower while the other 1 or 2 attack at the last known position or where the likely target is.
Each rear merchantman in the line within the convoy will be designated rescue boat. Escorts should concentrate on attacking subs.
Sailors from sunk subs are well down our list of priorities - we would only make an effort if it was deemed to be safe as they could be interogated for information. This is unlikely to happen at night.
Audacity to the front of the convoy with her escort. Maximum effort with planes - hopefully always a patrol up during daylight hours. When a sub is detected, it will be attacked and the report sent in to Walker ASAP. The plane will stay in area until escorts arrive to ensure that as much info as possible is passed on.

The emphasis will always be to attack any subs detected with as many elements as possible.

Fisherking

06-27-2011, 07:09

Moving Audacity to the front won’t make any difference in her operational abilities. It will just make her a better target.

She has no independent escorts, either. We have only the eight remaining escorts, seven corvettes and the Stork.

If a sub is contacted the escorts in that zone of responsibility are going to have to do the job and do it quickly.

With it being obvious that we are being hunted by a wolf pack a request for reinforcements needs to be sent.

Another two or three escorts would make it possible to be more of hunters than the hunted but at this point we are only able to defend the convoy and should not risk leaving any areas unprotected.

Franconicus

06-28-2011, 15:45

Now we have two players, one wants to place the carrier at the front and attack spotted subs with several escorst, the other wants to keep the carrier behind and attack only with single escorts. :dizzy2:
Any chance to get a common view?

ELITEofWARMANGINGERYBREADMEN88

06-28-2011, 16:27

I want to take JC!!!!! :clown::clown:

And you did post this in the wrong thread. :laugh4:

Franconicus

06-28-2011, 17:43

I want to take JC!!!!! :clown::clown:

And you did post this in the wrong thread. :laugh4:

Well, if you are already here, why don't you jump into the game?:laugh4:

Fisherking

06-28-2011, 19:08

No one said anything about using single escorts!

There are two escorts in each sector. That would be front, back and sides.

And no, I want to use the planes just as much but don't want to risk the carrier maneuvering far outside of the convoy.

ELITEofWARMANGINGERYBREADMEN88

06-28-2011, 20:51

Well, if you are already here, why don't you jump into the game?:laugh4:

Naval stuff ain't my cup of tea! Let that old guy KK beat up on the Germans! :laugh4:

King Kurt

06-29-2011, 17:10

Naval stuff ain't my cup of tea! Let that old guy KK beat up on the Germans! :laugh4:

Some respect for your elders please!!!!!

ELITEofWARMANGINGERYBREADMEN88

06-29-2011, 22:41

:laugh4::laugh4: KK!! Joke my friend,joke.

Franconicus

06-30-2011, 15:16

Chapter 11 – from dusk til noon, 20 of December

Walker’s convoy leaves the Adjutant behind and prepares itself for the night. Everybody expects that the Krauts will attack as soon night falls. However, nothing happens. Walker stares into the dark, but there does not seem to be anything out there. He went to the ASDIC-room, but there is only the noise of the convoy. Walker mistrusts the peace, he knows that several submarines are out there and he does not have the illusion that they are willing to give up.
At four o’clock Stork receives a radio message from England. WAC decided to send reinforcements, three ships from Gibraltar, two flower class corvettes and the already known HMS Stanley. Further more, a Black Swan Sloop which is already operating in the Bay of Biscay will be redirected to the convoy. Four ships, that will certainly change the balance of power to their favor. But until their arrival Walker has to defend the convoy with the ships he has. Walker goes on deck. Light fog is coming up. Walker wonders why the Germans hesitate to attack. Until know, they only attacked stragglers.
It is almost dawn, when Merigold reports a contact on the Northeastern side of the convoy. At once Walker gives her and Penstemon the order to chase the German submarine, if there is actually one out there. Both ships report of short contacts, but they are unable to detect the position of the submarine.
In the meanwhile, Walker receives a message from the Audacity. MacKendrick decided to start his planes with the first light of day and therefore he decided to place his ship a bit in front of the convoy. Walker curses. Right now, when the German begin to wake up, MacKendrick leads the only carrier to an exposed position. Yet, there is not a lot Walker can do. As he is at the rear of the convoy, he tells Lt. Connel of the Convulvulus to keep an eye on the carrier.
Moments later, Walker forgets about the carrier. Only some hundred yards in front of him, two torpedoes detonate. The target is the Switzerland a 9,000 tons freight ship. There is fire at the forward deck. Walker orders his sloop closer. The German must still be there. Snowflakes are fired, but Stork is not able to detect the submarine. Minutes later another torpedo hits the Switzerland, which begins to sink slowly. The crew tries to leave the ship in life boats. Still no signal from the German submarine.
On the southwestern edge of the convoy, Vetch and Rhodedendron detect a submarine. They begin to charge it immediately. The light of snowflakes and the sound of depth charges come from the left side of the convoy. The minutes pass slowly. Walker already gave the order for the columns to zigzag. Then Vetch reports that a submarine went up. The two corvettes open fire, but the submarine tries to escape. Rhodedendron tries to drive against it, but it fails the target. The submarine seems to be seriously damaged, but it is still swimming. German sailors jump into the sea. Then all over sudden, the submarine goes down and disappears. Vetch and Rodedendron leave the place of combat without caring for the Germans and return to their guarding positions.
There is not much time left to be happy about the success. Minutes later there are three detonations in the middle of the convoy. The captains of the freight ships begin to panic and order is lost. Finally Walker finds out, that three ships were hit, two sunk immediately, the third one is still running and will probably be able to continue the journey. The Switzerland is still swimming, too. The fire went out and the crew returns to the ship. Hopefully she will be able to keep our speed, Walker thinks. However, at this moment, two torpedoes hit the damaged ship, which begins to sink. An hour later, it is gone.
This is the last event. The sun comes up and the fog slowly disappears. Walker’s convoy is still heading northwest. During night, it lost three ships, but sunk one German boat. But the battle is not over. Walker knows that both sides are waiting for reinforcements and when night comes, the battle will continue.

Franconicus

07-11-2011, 15:51

???

King Kurt

07-12-2011, 20:00

Sorry Franc - I was waiting for some options/requests - do you want us to come up with some suggestions??

Fisherking

07-13-2011, 18:12

Same here. We are already doing what we can to keep going.

I would like to see the carrier come back to the rear where we can keep a better eye on it but beyond that we will just keep up maximum effort until the other ships arrive.

Franconicus

07-17-2011, 08:25

Course?

Fisherking

07-17-2011, 13:18

Current Location?

Under the circumstance more frequent zigzags and course changes are in order but losing the pack is unlikely. They need to be damaged or sunk and setting a course to intersect with the reinforcements is the best bet.

Do you think we can get away with launching and recovering aircraft at night with snowflakes?

This should work. Also subs are more likely to operate on the surface at night which would make them more vulnerable to air attack. Launching a few random snowflakes might silhouette a sub or two and we could reduce their numbers and force them under.

Not to mention the effect ships guns would have on them.

Franconicus

07-18-2011, 16:00

Location: CF64

Could you please explain your ideas about using planes at night and snowflakes?

King Kurt

07-18-2011, 16:53

I am not sure about lauching planes at night - The Fleet Air arm did do it, but it would highlight the carrier and make it a target. Better to aggressively patrol and use dummy attacks to lure U Boats to that area.

Fisherking

07-18-2011, 18:25

We need to use snowflakes occasionally to try to spot surfaced subs.

The pilot only needs to see up and down at take off and landings. An escort near the carrier launches snowflake when a plane need to take off or land.

The planes are the best weapon against surfaced subs that we have.

Franconicus

07-28-2011, 13:51

Chapter 12 – from noon until dusk, 20 of December

Walker calls the carrier back to the rear of the convoy, close to the "Stork". He also sends instructions to the other escort ships, so that they know how to behave during night. Walker tells them to use the snowflakes more aggressively and especially to use the Martlets also at night. As expected, Mac Kendrick protests. He argues, that it is much too risky to start and land during night and that he has only got four planes and that the stress is too much. Walker ignores him and soon the Audacity is on her way to the rear of the convoy.
If Walker thought the next raid would come at night, he is wrong. At 13:48 the Martlet patrol reports of two unidentified planes, coming straight to the convoy. Walker immediately alarms the escorts and a second Martlet gets off. The gunners sit at their anti aircraft guns, ready to repel any air raid. However, only the humming of engines shows that there is something going on above the clouds. Then a four engine bomber dives through the clouds. First it seems as if the plane would go straight in to the convoy, but then it falls straight into the sea. A quarter of an hour, the two Martlets return. Brown, one of the pilots, flies twice across the convoy, shaking his wings. When he finally got down, he reports that he shot down two German Condors.
Walker sends a report to the WAC. He also receives two radio messages. First one is telling him that the reinforcements will arrive next afternoon. Second one is telling him, that the United States are now at war with Germany.

Fisherking

07-30-2011, 14:13

Have the planes concentrate on scouting the forward area of the convoy until near dark and then concentrate on the rear area from dusk until dawn. Making occasional sweeps all around.

If searchlights and snowflakes don’t turn up a sub in the night, perhaps they will give themselves away with smoking on deck or the conning tower or show a light through the hatches. We can only hope. The pilots may get lucky.

We should use more active ASDIC until dark. In the night they will mostly be on the surface anyway, charging batteries and making surface approaches.

King Kurt

08-02-2011, 17:00

I am still not sure about using the planes at night. With only 4, we can't afford to loose any. Also we have to think about the effect on the pilots - they can't work 24/7 . Perhaps we should do it for tonight - we know the U boats are close - and stop from tomorrow as reinforcements are on the way. We should certainly think about a mock attack when the plane is landing.

I agree with Fischer's search paterns. I also think we should do a violent course change a couple of hours after dark - turn to the west, sail for 4 hours , no Zig Zag then resume standard course. if we could combine that with a mock attack - say to the east, we may throw them off tonight, especially as we have not done this before.

Our HF/DF hasn't come up with anything yet - perhaps we should concentrate on that at night

Fisherking

08-02-2011, 17:53

It was never my though to keep using the planes every night.

But this night they will not be expecting it and it may pay big dividends.

Once we have more escorts we will have more options but for now we are too few to hunt and kill them any other way.

Without their own searchlights the planes will not be highly effective in finding the enemy but for now we are desperate enough to try it.

Even if we get one sub this way it is worthwhile and they will not have faced aircraft at night before.

The course change is not a bad idea but I think the mock attack would better be left for some other time.

more lights will not be much of a distraction under these circumstances and pooling the escorts away from the convoy is too risky at the moment.

King Kurt

08-02-2011, 21:12

Lets go with just the course change and the air attack then

Franconicus

10-30-2011, 20:09

I think it is time to end this game officially. I must declare the Germans as winners.
The game did not run as good as I hoped it would, but I learned a lot more about the sub warfare in WW2 and I hope you had some fun.

ELITEofWARMANGINGERYBREADMEN88

10-31-2011, 13:45

You being bias :laugh:!

Don't worry Fran, it is always pleasure playing in one of your IH's!

King Kurt

11-07-2011, 14:19

Fran

As you can imagine, I have enjoyed this immensely and am sad it has finished. I thought the idea was a good one, but it is difficult to manage an IH which involves submarine warfare I think. The mix of long periods of nothing happening mixed with short sharp periods of frantic action is difficult to simulate.

Franconicus

01-02-2012, 11:19

The game ended some time ago, but I guess I still owe you a kind of summery about the tactics from the other side.

Although the game was very bumpy, I have to say that I learned a lot about the warfare in the Atlantic.
One thing that really surprised me was, that the Germans in reality knew very little about the abilities on the other side, while the Brits had a rather clear picture. The reason for this is simple, the allies were able to take prisoners - even if there were only few - and later they were even able to capture subs. Germans did not have a chance to capture a corvette or to take prisoners.
Although the allies had a rather good knowledge about the subs, in the time of our game they underrated the ability of the German sound locater. It was able to detect the direction of an acoustic source over a long distance with high accuracy and could identify the source as a warship or merchant. In real life walker tried to simulate a battle behind the convoy to lure the subs from it. This had to fail, obviously, because the Germans could easily identify the movement of the warships. As a result, Audacity was sunk.
However, in reality, the German made some terrible tactical mistakes, cause by their ignorance of the other side. First of all, their common defensive maneuvre once they had been detected, was to dive as deep as possible, moove slowly and silently with surprising turns. If the crew on the Asdic was well trained and if the Escort ship had enough time, this tactic usually failed. In the beginning of the war, the ash cans were set on a maximum depth. The subs were able to dive even deeper so they could escape easily. However, the Brits changed the setting quickly and were then able to attack subs at any depth. Furthermore, the Asdic worked very well in the depth, so depth was no shelter for the Germans. However, the Asdic had a weak spot, which was right below the surface. Here refelxions disturbed the signal and the device had a minimum angle. Germans never learned about that during the whole war.
So now to our game. I tried to recruit a team of experienced submarine veterans and therefore looked at the German forum of Silent Hunter. In the beginning this worked rather good, although it seemed to be hard to explain the concept of the interactive. Nevertheless, there were some high skilled players, burning to change the way history went and to teach the Tommis a lesson abouzt naval warfare. Then things went out of control (I guess it was when the Gestapo interfered). The players blamed me to be someone from their forum, who tried to mess around with several identities and tried to fool the rest of the players. It ended when the mod attacked me and demanded me to lay open the link to the other team. At this point I decided to make a break. I stopped the game and asked the most motivated and engaged player if he wants to go on alone.
He did a rather good job. He set up his strategy on what is known about the technologies today.
In the beginning he set three ships to a line west of Gibraltar. They had to be under water all the time to listen for any allied ships. They only came up during night to load their batteries and to send messanges. During this, the Germans tried to get as many boats to the expected combat zone as possible.
The Germans detected the convoy - or rather said the two convoys which left Gib almost at the same time. They also decided to attack the bigger one, yours!
In the beginnig, they where still waiting for reinforcements, so they kept quiet in the distance, still under water all day long, coming to the surface only for some time at night.
Then they finally attacked. The subs had the order to follow the convoy under water during day with a rather big distance - no chance to detect them with planes. When night came, the submarines came up and got into the right position to start their attack. The boat where devided into two packs, so they could attack from both sides. The attack itself was done right below the surface of the sea. So the boats could not be seen nor detected by the Ascdic. It would have taken a lot of luck to get one of the boats into the range of the ASDIC. So the could penetrate the convoy, attack and disappear.
For me it was interesting to see that the countermeasures - using planes at night, more light etc. - where not appropriate for this tactic. It was obviously that the Allies had not noticed the way the Germans changed their tactics and therefore were not able to react. Maybe it would have been wise to rescue some of the German sailors from a sunk sub. Humanity always pays!

King Kurt

01-06-2012, 13:45

Fisherking

01-07-2012, 10:59

It is likely I know much more about the U-boats than the escorts.

I felt like a sitting duck during the whole game. However, I think KK is right. The subs had to stay on the surface during the day to keep up with the convoy. While they could locate them at long distance staying in contact and getting a shot was not quite so easy. Following on the surface or running a head and occasionally submerging to get bearings were the tactics.

Daylight attacks meant getting in the path of the oncoming convoy and waiting. Night attacks could be made on the surface, running in for some quick shots and back to safety.

Aircraft made shadowing the convoy much more difficult and kept the boats farther away from their targets. Planes at night and star shells would have been a real damper on their preferred hunting methods.

If there were aircraft they could usually be seen a periscope depth even in the North Atlantic. Other seas they could usually be seen at much greater depths. Walkers tag team approach with his escorts meant that they were more able to maintain a contact, as the ship attacking lost the ping as they passed over the sub.

One way or another we should have been able to detect something when they were in the area but this never seemed to happen. No radar or sonar contacts to speak of.

Also in rough seas sound contacts were lost because of the wave action and contacts needed to be maintained visually. The smoke of the convoy could be seen at about 25 miles in clear weather but in storms it was no easy task.

I am sure that Kurt was as disappointed as I was when it ended just as we were receiving some reinforcements.

Franconicus

01-09-2012, 18:36

Thanks for the feedback Franc.

Like you, despite having a great interest in naval matters, I have learnt a lot about the warfare that made up the Battle of the Atlantic. As an aside, it is interesting that there is not a greater interest in the Battle of the Atlantic in the UK. The battle was arguebly as important, if not more so, than the Battle of Britain, but our interest in it - me included - is nothing like that shown for the air battles of 1940 or say El Alamein. I knew of Walker, but not much detail, so it was good to find out more about him.

As to the german tactics - they seem sound. However I wondered how they managed to keep such a good contact with the convoy when they spent so much time underwater? My thinking was always guided that the U boats needed to spend most of their time on the surface to have the speed to keep in contact with the convoy, especially as we changed directions a lot and used the storm to mask our movements as well.

However, overall, it was great fun and you did a great job of keeping the IH moving - especially after the german Silent Hunter forum had you down as some sort of Warman 8 clone!! i felt the only dissapointment was that only a few people - mainly me and Fischer - kept the faith with it. Your efforts deserved more.

So well done - perhaps we will have another one one day.

About the importance of the Battle of the Atlantic: I guess it was the most important one of the British. The Battle of Britain was great, of course, but I never had the impression that the Germans had the slightest chance to win it. So, although the Brits fought bravely, in my eyes it wasn't that important. We also discussed El Alamein and I already made my resons that the Germans would not have won, if Rommel broke through. German lines were too stretched and most of the German troops were in the East. However, if the Germans had won in the Atlantic, Britain would have had to give in, maybe not surrendered, but a cease fire. Time enough for the Germans to invade Russia.

About the Germans keeping contact: the microphones were able to locate the convoy for hundreds of miles. So there was no chance to hide it. The subs followed the convoy out of the air patrols. Remember, that it was December, long nights, enough to get in front of the convoy and to attack.