i think your right...i've had a read of some books and hydrophones were invented around 1917...(with ASDIC not far behind ...strangely ASDIC got shelved untill much much later even tho it was being tested during WW1)
and here's no mention i can find of German Subs carrying hydrophones..
one thing the sim is missing most i suppose is crew voices ...i've knocked up a small sound pack to add some voices to a few of the commands...just to add a little more atmosphere
here's the link
http://www.ebort2.co.uk/files/SOF_voice1.zip
been having a small look at the campaign and how it works as well
and even tho it at first sight might appear to be purely scripted..it is in fact at least as dynamic as the SH3 campaign..or random is the best word..(for both)..with shipping routes ..target areas...probability frequency and type of shipping along those routes and in those areas being randomised and so on ..which puts it on a similar level as indeed SH3 etc...and it's editable also so this is purely as stock..could be worked on fairly easily...
the game certainly isn't an easy one....
so far i have yet to actualy survive a depth charge attack!!!
and i am gradualy getting used to there being no auto TDC at all...(always been quite lazy on that front with the other sims)
everything hinges on the scope not being spotted...and fortunately you can see the ships with the scope just breaking the surface..without them spotting you...tho if you want the ships to display on the plotting map and the targeting map in the scope room you have to raise it further..and then they can see you (within a certain range depending on the weather etc etc)..so it's a nice balancing trick...and offers some interesting choices as you try to plot your torps angles etc..it's not over complicated at all, but it still has to be gotten right or you just waste the torps...(and you don't have many)...it's much much easier up close of course..but then you risk certain death from the escorts if they spot the scope....you can't dive fast enough to evade them..(hence the fact i have yet to survive a DC attack lol)....so it means i need to attack from further away...and that means lots of wasted torps...i'm pretty sure there's no auto TDC...there were no targeting number crunchers for the WW1 subs AFAIK so this is realistic ..either way it works well and adds a lot to the game