Type IX c / IX c40 hull differences

[Capt Kremin]

Can anyone help with an easy/hard question, what is the differences between a Type IX c and a IX c40 hull ?, it even seems to me that depending what you read even the dimensions of each are variable.
 
Jon

[dbauer]

Hi!
Type IXC  Length = 76.76m
                  Beam = 6.76m
 
Type IXC/40 Length = 76.76
                       Beam = 6.86m
In a 1/72 Model they would be almost identical except the cut out bow on the IXC/40.
regards,
Dan 

[dougie47]

Hello Jon and Dan,

As Dan has mentioned there are some minor differences in beam and height. But as for shape I'm not too sure if there was much of a visible difference. For example if you saw a photo of a IX in dry-dock I'm not sure I could tell whether it was a IXC or IXC/40. Can anybody see an external difference?

The cut-out bow, which reduced diving times, may be a confusing issue. If you look at the Vom Original book for the IXC, on page 60 there is a drawing of a IXC without the cut-out, and on page 62 there is a drawing of a IXC/40 with the cut-out bow. However, this does not mean that the cut-out bow was only fitted to IXC/40s or that all IXC/40s has this cut-out bow.

On page 33 of the Original book, you will see a list of IXs which were refitted with the cut-out bow. If you look at the boat numbers you will see that most of them are IXC/40s. However, U 516 and U 518 were Type IXCs which were refitted with the cut-out bows. So the cut-out bows were not just fitted to IXC/40s.

There were also quite a number of IXC/40s which did not get the opportunity to receive the cut-out bow modicfication (eg U 167).

Dan, I will be designing a replacement U 505 emblem decal soon. I think Revell copied Hoegel's book, which suggests red, but you are right that U 505 didn't have a red background to the emblem.

Cheers,

Dougie

[Capt Kremin]

Thanks guys,
 
Your replies back up my own research on shape/size. I'm thinking 10cm in 1:72 scale is 1.3mm, which is less than the error in length on the Revell 1:144 scale type VIIs. Not having assembled the hull at all it may well be even closer, if I'm lucky!
Dougie, I can't remember where I have seen it but I'm sure I have seen picture of a IX D (U 875?) with a cut-out bow as well, just to muddy the water. Also for some stange reason the U 534s curators desided the display her with a blown up version of the diagram in Vom Original on page 62 which has a cut-bow when U 534 clearly does not, go figure.
 
My plan is to model the U 534, hence the question, now all I need is some decent overhead pictures of the schorkel as it looks a cludged and rushed affair with the fairing covering the exhaust and inlet pipes, unlike other schorkel layouts I have seen.
 
Many thanks,
Jon

[dbauer]

   Hi Again!
I asked my " resident expert" my father the question on the Type IXC/ C/40 differences.  He told me that U-805 originally had the standard Type IX C hull when first built.  When U-805 returned from Trials she was fitted with the cut out bow.  He could not recall any major differences.  It could be some internal differences with equipment. So the question still stands. Sorry but not so much help here. 
Regards,
Dan
.

[Capt Kremin]

OK guys,
 
I apologise in advance for the length of this post.
 
According to Köhl and Niestlé in Vom Original, the main difference between the IXC and the IXC/40 is the fuel bunkerage (is that a word?) was increased by reducing the weight of the engines and other equipment, hence the quoted increase in range.
Rössler and Lehmanns Verlag in Geschichte des deutschen Ubootbaus quote similar differences in beam, i.e. 6.8m and 6.9m respectively.
 
Now to muddy the waters, hear me out on this as this is not meant to be an argumentative statement, more or a what if.
So lets start with facts there are many differences in type VII and type IX boats depending where they were built, flood hole and railing patterns to name 2.
 
Is it possible that the the different yards produced slightly different sized hulls?
 
Now lets add a bit of conjecture. Where do the dimension figures for IXC and C/40s come from, the build drawings or actual measurements, (if measured by axis or allied), either way there could be errors between them and the real boats.
 
Could the various books and websites be quoting from originally one source, which could be in error?
 
E.G. I have a set of figures that says IXC surface speed 18.3 kts IXC/40 19.0 kts, could these have been measured based on individual boats, if so could the C have had a deck gun. Also draft is quoted as being different between the two boat types, assuming minimum draft quoted, surely that would depend on the weight of the boat at the time and maximum buoyancy and maximum draft is irrelevant as they sink!
Generally the dimension figures for the VII C and VII C41 are identical  for everything other than max depth, due to the improved steel used.
 
This would imply that a year suffix is an incremental improvement, possibly true of type IXCs (In this case fuel bunkerage and equipment weight)?
 
 
Just a thought on this as I type, it would be possible to measure the U 534s beam just aft of the tower, probably the widest point with a simply tape measure, wish I'd thought of that at Easter when I visited her. Ho hum I feel another road trip coming on.
 
Jon

[dbauer]

  Hi Again!
Considering the different companies that made the Type IXs as well as the Type VII's I am sure there were suttle differences in all the boats.  However, they were all given the same set of plans and standards, and the Germans were and still are very exacting in their work.  So the differences were very slight.  I would agree with you on the differences being the fuel bunkering. 
As far as Booten recieving the cut-out bow and others not; we have to take into consideration the effects on the German Shipyards from 1943 onward. They were doing amazing things even during almost constant bombing from the Allies. And I am sure this had a major effect on refits on the Booten.
As far as the over all effect of the cut out bow; my Father said the cut out really did not help all that much with the diving time of the Type IX.  By 1943 onward the Allies were winning the  Radar Technology War and the U-Boots were the Hunted instead of the Hunters.  Remeber because of the basic hull design, the Type IX was nick named , "Sea Cow".  So the Germans were trying to shorten the time to dive and give the Boot a chance to evade attack.   But with the adavances the Allies had, and the Hunter/ Killer groups the Ubooten were finished.
Regards,
Dan