writing a book/last days ww2/new uboat/new weapons?

[mallyob]

Hi guys , I have started writing a book,based on a little fact but NOT entirely! , set in the final days of WW2, it centers around a new and very secret Uboat,codenamed "Seascorpion". The boat is based around a type xx1 electroboat. Now...I want to attribute certain characteristics including new weapons to this Uboat, I have only started my research but, are these things sort of viable or do they sound ridiculous!
1) codenamed "vesuvius" an upward firing, slim (20cm),shaped charge, acoustic torpedo,range 600mtres, set internally, much like the polaris missiles of today. They would be used to "discourage" depth charge attacks and make it a very dangerous place to be/around (within 600metres), above a Uboat.
2) Underwater "chaff", much like the aluminium foil strips used to confuse aircraft radar at the time, these would be shot from differing points on the boat, (little missiles), set to detonate at different times, the aim would be to confuse the sonar systems of any hostiles and allow time for the Uboat to effect an escape! There will be much more but I've only just finished the first chapter! many thanks for any comments. mal.