977 U-boat

[joegrundman]

I recently read this pretty good book, U-boat 977 by Kaleun Heinz Schaeffer

it's available as free pdf download here and i fully recommend it :

http://www.archive.org/details/977uboat001463mbp

however i made a few notes that I think would be of general interest here, but i do appreciate that this is only one source, and not necessarily to be considered definitive:

1. A description of the TDC, which the author refers to as the "attack table"

The torpedo-officer at the attack-table reports "Lined-
up" and the switch is made by which the attack-table
is connected with the gyro-compass and the attack-
sight. The mechanism churns around and two red lamps
indicate that the process of calculating the information
which has been fed in to it is not yet completed. The
lights go out after a few moments, and the petty-officer
at the attack-table reports the resulting settings to the
torpedo officer. From this point onwards our own
alterations of course are of little importance, being allowed
for automatically. The target must simply be held in
the crosswires of the attack-sight in order that the apparatus
can do its job. The torpedo-officer gives the
order "Follow" to the attack-table. A lamp glows, and
the attack-table is now controlling the binoculars on
the bridge. Meanwhile the constantly changing firing-
settings are being transmitted automatically to the
torpedoes and set on their angling mechanism. With this
system we can fire at any moment and on any course,
provided that the 90-degree limiting angle is not exceeded. The torpedoes will run to a pattern that spread
over roughly a ship's length by the time they reach the
range of the target. We turn to our attacking course.

pp87-88

From this it appears there was a time delay between programming the TDC and it being ready, but once ready updates by changing periscope angle are instantaneous - this would be akin to a 5 sec (for example) delay between selecting auto-update on the TDC and it being ready for use.

I understand that the real TDC had input for target course rather than AOB, and hence presumably the submarines' own heading would be fed in automatically from the gyrocompass - this would account for his statement that changes on own course would be automatically factored in.

This important functionality is missing from the SH3 TDC

however this line "The torpedo-officer gives the
order "Follow" to the attack-table. A lamp glows, and
the attack-table is now controlling the binoculars on
the bridge." confuses me.

2. The sound of ASDIC

The convoy was steaming away now, its propellers
barely audible. But three destroyers were after us, and
before long the sound of their Asdic,like fingernails
run over a comb, grew all too familiar. Another of their
Asdic devices rattled like peas in a tin, a third screeched
like an ancient tramcar taking a curve. We weren't likely
to forget this experience. I thought of the man who went
out to discover what fear meant He should have been
there.

pp103

only the third variation he describes could be considered similar to the sound we are familiar with. I like the idea of a mod changing it for the comb or peas effect

3. Pitch and roll in heavy weather

FOR FOUR weeks the wind had been howling
from every quarter at 55 to 60 miles an hour, with heavy
rain and the thermometer only a few degrees above zero.
I was up on the bridge. There was of course no protec
tion there, just the icy steel bulkheads, so it was impos
sible to work up any warmth. Lashed to the rail as I was,
the leather safety-belt reinforced with steel bit deep
into my ribs. It had been known for the watch on the
bridge to be washed overboard in heavy seas in one
boat the relief had gone up to take over and just found
no one there. The force of the seas breaking over us
now was terrific, but the boat shot on nevertheless like
an arrow, with very little pitching or rolling and the
waves over us over a breakwater.

pp117

the final sentence is of interest here - the author suggests that U-boats were really quite stable in even very rough weather

4. radar decoys

couldn't help thinking this superfluous, for inside the
boat it was as good as pitch dark anyhow. Next the Asdic
decoys were thrown out, and we began to fill balloons
with metal strips attached, which were to be released
when we surfaced to float low over the water and fox
the enemy radar.

pp143

radar decoys!! i never knew - this would be nice in game!

[onelifecrisis]

Originally Posted by joegrundman

This important functionality is missing from the SH3 TDC

radar decoys!! i never knew - this would be nice in game!

Too right. Two for the SH5 requests thread, perhaps?

[Hitman]

From this it appears there was a time delay between programming the TDC and it being ready, but once ready updates by changing periscope angle are instantaneous - this would be akin to a 5 sec (for example) delay between selecting auto-update on the TDC and it being ready for use.

I understand that the real TDC had input for target course rather than AOB, and hence presumably the submarines' own heading would be fed in automatically from the gyrocompass - this would account for his statement that changes on own course would be automatically factored in.

This important functionality is missing from the SH3 TDC

however this line "The torpedo-officer gives the
order "Follow" to the attack-table. A lamp glows, and
the attack-table is now controlling the binoculars on
the bridge." confuses me.

Yes theer was a time delay. The TDC was, even if a hugely complicated, basically and analog computer. I.e. it worked like an old clock, with lots of wheels, springs and such. Therefore you entered data on the dials through the handwheels above and below the case (And never by moving the dial needle directly like we do in SH3 , they were too delicate for that) and then you switched it "on", allowing for some seconds calculation-then it gave the signal with the red lamp "ready".

What was fed in was the AOB, not the target's true course (Inversely to what the TDC on US subs admitted) and what Schäffer refers to as own course changes being unimportant is that the TDC allowed compensation of those changes, not of enemy course changes. But yes in SH3 if you change your own course, the solution gets screwed up.

As for the last sentence, when the lamp glows (It was a blue lamp) it meant "Lage folgend" (Following AOB) and it's the same as when you lock the TDC and the dials are updated by the movement of your optics. That is historically correct. I think that the reference to the TDC controlling the binoculars is an error in translation, I have seen that happen many times with books written originally in german when it comes to technical terms (Heck, I have even detect errors in the official US Navy translation of the german Submarine commander's handbook of 1943!!!).

[Torplexed]

This is the part of the book I've always been suspicious of since I first read it years ago.The author describes sinking a US destroyer on Christmas Eve 1942...

The range was 400 yards; we could get no closer, for
300 yards was the danger limit. If we had gone much
nearer, with all the explosive we had on board we should
have been in danger from the shock-wave of our own
torpedo. Many U-boats were in fact lost this way.

Suddenly there was a flash of red, blue, yellow, green,
and an enormous waterspout came tumbling down. In a
minute or two the dark shadow ahead had disappeared.
More than that, there wasn't a lifeboat, not a raft, not
a sign of life of any kind. Sunk without trace as she was,
it was pointless to look for survivors.

It had been an even chance whether we or the enemy
were going to go to the bottom, and fate had decided
to send them there. However, that was how we did in
fact spend our Christmas 1942.

A pretty vivid description, but according to records there were no US or Allied destroyer sunk on that date.

[Annatar]

The introduction chapter is... interesting, to say the least.

[joegrundman]

Hey Hitman and OLC, nice to see you both!

Thanks for the update on the workings of the TDC - it would be nice indeed if the SH5 tdc can account for changes in own ship course - and i am persuaded by your opinion that the mystery sentence was a mistake in translation.

@ torplexed

well, first-hand accounts are notoriously unreliable, since memories are amazingly poor even with things people apparently remember very clearly, as well as then being subject to exaggeration, storytelling and ideology in reporting the memories. It is also the case that people make mistakes in the first place, and these mistakes get remembered as fact.

Despite these limitations, first-hand accounts remain extremely valuable and entertaining to read.

So with the destroyer issue, you have several options including, but not limited to:

a) he misremembered/misreported the date
b) it was misidentified as a destroyer
c) the target wasn't actually sunk, but the ships lost contact
d) the event in question never happened

but actually it is not these sorts of happening that i highlighted as being of interest for the running of the simulation - it's still a worthwhile read though and you can't beat the price!

[coronas]

Very interesting reading.
Thanks for sharing, Sir!

[Jimbuna]

Never read this book....cheers Joe

[Laufen zum Ziel]

Just downloaded. Thanks.

[Hitman]

The introduction chapter is... interesting, to say the least.

You mean the introduction by Nicolas Montsarrat?

Yeah, quite interesting....how a man like him still remained embeded in the prejudices and half-sided vision of the british propaganda and traditions even long after the war. Of course germany was not a nation of good will persons hijacked by a uncontrolled band of nazis, but then again WW2 was a direct consequence of WW1 (And the humilliating and unacceptable conditions of the Verasilles Treaty, as well as the post war plundering of Germany by victors) and WW1 itself was a direct consequence of Britain pretending to rule the world and not let others do the same

Montsarrat just sees how germans fought aggression wars, not how they were driven and cornered into fighting them, just as Japan was forced to in WW2. No, I don't justify at all wars, let alone aggression wars, but anyone with some intelligence should at least think that unfairly pushing a proud nation like germans or japanese to the limits would trigger some kind of response...

[Kapt Z]

[quote=joegrundman;1086186]
the author suggests that U-boats were really quite stable in even very rough weather[quote]

That does seem hard to believe. I myself have seen photos taken from the bridge aft that show a u-boat rolling to (what appears to be)about 50-60 degrees in a storm.

40,000 ton aircraft carriers got tossed like rowboats in bad storms...

a 700-1200 ton u-boat would have been stable on the surface?

[Sailor Steve]

Originally Posted by Hitman

You mean the introduction by Nicolas Montsarrat?

Yeah, quite interesting....how a man like him still remained embeded in the prejudices and half-sided vision of the british propaganda and traditions even long after the war...Montsarrat just sees how germans fought aggression wars, not how they were driven and cornered into fighting them...

I have owned a copy of the book for many years, and I've always been puzzled by Montsarrat's comments, mainly because in his own personal writing he was just the opposite...or just the same, depending on how you look at it. In The Cruel Sea he talks about the brotherhood of all sailors, and how the Germans were just doing their job like anyone else, and in his short stories you get more of the same; but when writing the preface for Schaeffer's book his attitude is "don't believe them - they really were all hate-filled Nazis!"

[Torplexed]

Originally Posted by joegrundman

So with the destroyer issue, you have several options including, but not limited to:

a) he misremembered/misreported the date
b) it was misidentified as a destroyer
c) the target wasn't actually sunk, but the ships lost contact
d) the event in question never happened

but actually it is not these sorts of happening that i highlighted as being of interest for the running of the simulation - it's still a worthwhile read though and you can't beat the price!

Those are good possibilities. It could even be an error in translation. Another possibility would be an attempt to embellish things by the author due to pressure by the publisher. A lot of books printed in the decade after the war like this one (1952) tend to be a bit muddled in the facts in the hasty desire to feed the public hunger for what took place on the other side during the war. The copy I have is a pulp reprint paperback from 1964 maybe printed with the idea of better grabbing readers by having it's title in bold stencil letters....U-BOAT 977.

[bobchase]

[quote=Kapt Z;1086354][quote=joegrundman;1086186]
the author suggests that U-boats were really quite stable in even very rough weather

That does seem hard to believe. I myself have seen photos taken from the bridge aft that show a u-boat rolling to (what appears to be)about 50-60 degrees in a storm.

40,000 ton aircraft carriers got tossed like rowboats in bad storms...

a 700-1200 ton u-boat would have been stable on the surface?

It would depend on the sea-state how the U-boat behaves. I've never been across the Atlantic on anything small than a DE but ships are much more stable than what is modeled in SH3. The word that comes to mind is ponderous and the larger the ship the more ponderous they are. The airdales will tell you that a CV will rock & roll in heavy seas but that is both their bravado talking and their relative world of living inside a giant. For them, their ship really is moving hard in those seas but let a DD or DE come alongside for refueling. If they pay attention, what constitutes rock & roll gets seriously re-written when you watch the smaller ship half-buried in seas that cause a carrier's deck to only pitch or roll +/- 5 degrees.

A little DE does move about in almost any sea so one would presume that a surfaced U-Boat would behave much like that. However, there is a sea-state where the swells (waves) are very sharp, almost vertical, and far enough apart where a DE's hull won't rise to meet the swell. The water just simply breaks onto the foredeck and rolls off at the forward the breakwater. Down below you'd think that you were in much calmer seas if it wasn't for the big 'shudder' that goes though the ship every time a wave breaks. On a U-Boat, in that sea state, one would imagine that the sea would simply roll over the whole sub and never even break.

Bob

[Hitman]

However, there is a sea-state where the swells (waves) are very sharp, almost vertical, and far enough apart where a DE's hull won't rise to meet the swell.

Yeah, the armonics of the waves is hugely important in what you actually "feel" on the boat. I myself have been mainly on small sailboats, but in my experience those pesky small and hard waves that hit against your bow and continuously brake your ship produce a much bigger effect than the heavier and larger roll waves that move your boat smoother up and down coming from behind or 3/4 behind