Mr. David Tompkins, a writer in the UK, is seeking help on “SONAR training records used by the SONAR / radar training schools in the U.K. during WW2. I assume it would’ve been for the ASDIC systems? I wondered any US SONAR recordings, or something similar to what you have, might’ve been used by the British schools as well. I’m grateful for any guidance or suggestions of historians or experts I could contact.” He can be contacted at rondohat@gmail.com