Technology and Operations
This forum is for discussing technological & operational matters pertaining to U-boats.
Re: Depth Charges and ASDIC/Sonar
Posted by:
Sander Kingsepp
()
Date: August 19, 2002 09:35AM
Robert C. Stern describes the “Tarnmatte” as one of the two German anti-radar coatings (“Alberich” was essentially an anti-sonar coating as already noted):
“... developed by a Professor /Ludwig??/ Wesch of the Weltpostinstitut in Heidelberg. Tarnmatte was developed to be specifically effective at the 9.7cm wavelength of the H2S radar used by the RAF from 1944 on. It consisted of 2cm-thick sheets of synthetic rubber (Buna) with iron oxide powder content. The frequency of radiation which this material absorbed was a direct function of its thickness, requiring critical manufacturing tolerances. Because it was a flexible material and therefore able to cover complex shapes, Tarnmatte was adopted exclusively to cover the Kugelschwimmer-type snorkels introduced in 1944.
IG Farben developed an alternative material, known only as the IG-Jaumann Absorber, which had superior absorption characteristics compared to Tarnmatte but was much harder with which to work.”
(Type VII U-boats, p. 131)
USN seems to have preferred the term “Wesch” coating instead of the “Tarnmatte”. IJN I-58 CO Comdr. Hashimoto Mochitsura (who sank the USS Indianapolis) was questioned about the same invention post-war.
[www.history.navy.mil]
Regards,
Sander
“... developed by a Professor /Ludwig??/ Wesch of the Weltpostinstitut in Heidelberg. Tarnmatte was developed to be specifically effective at the 9.7cm wavelength of the H2S radar used by the RAF from 1944 on. It consisted of 2cm-thick sheets of synthetic rubber (Buna) with iron oxide powder content. The frequency of radiation which this material absorbed was a direct function of its thickness, requiring critical manufacturing tolerances. Because it was a flexible material and therefore able to cover complex shapes, Tarnmatte was adopted exclusively to cover the Kugelschwimmer-type snorkels introduced in 1944.
IG Farben developed an alternative material, known only as the IG-Jaumann Absorber, which had superior absorption characteristics compared to Tarnmatte but was much harder with which to work.”
(Type VII U-boats, p. 131)
USN seems to have preferred the term “Wesch” coating instead of the “Tarnmatte”. IJN I-58 CO Comdr. Hashimoto Mochitsura (who sank the USS Indianapolis) was questioned about the same invention post-war.
[www.history.navy.mil]
Regards,
Sander
