Spurred by this image on IWM (which I posted on twitter, out of interest's sake) "The water test: a hull-immersion test for tanks", Terence Cuneo. Art.IWM ART LD 3095 The Water Test : a hull-immersion test for tanks There were some questions on posed on Twitter to which I don't know the answer. First of all, what's going on here? The hatches of the Churchill in the midground are open - does the water look less deep than the hatches to you? Was this a standard test done when tanks were manufactured? Is this related to preparations for, say, D-Day? Unfortunately the image is not given a date on the IWM website. However, there are a couple of other Cuneo sketches related to the Churchill on the IWM site and they give a date of 1943. One of them is titled "On the strip-line: Churchill tanks being dismantled" which I would guess has to do with the Churchill rework programme. On The Strip-line: Churchill tanks being dismantled Thoughts?