ADP wrote:
I think I was one of the "experts" who took part in that discussion a year or two ago (though retired RCN, not USN), and yes - I find it very hard to believe that PE could detect anything on passive sonar when travelling at 25 knots. I believe the GHG was a very capable system however - is it possible that PE slowed periodically to listen?

Well, the books say nothing about that. Also, at the time of "detection" the germans had for sure NOT slowed down. Either the wonderweapon was so good that post-war they hide that secret - and you are part of that world-wide-conspiracy who fool us normalos... or it was an accident. They heared something and - just like a jackpot at the local Lotto, they detected the ships at correct places....  Now you can lift that secret - even if the NSA and whoever is involved will capture you....