Admittedly ferry gliding a 70ft narrow boat for the first time will concentrate my mind somewhat, but at a displacement of 25 tons I don't even want to imagine the damage I could cause if it all went wrong. So I think I will take it quite easy, and I don't need unnecessary self-imposed excitement at my stage of life, been there dun that!!!, My engine is the standard Beta 43 driving an 18" Crowther propeller, so I hope it will be up to what I ask of it. Thank you all again, this is giving me plenty to think about and the link with the tidal gauges is excellent and live webcams as well, 90 cubic m of water per second is a lot of water, certainly far more than can come out of some CRT water taps!.