Range for some German aircrafts

Thanks for replying. It is not necessary to know exactly how much longer the range would be with auxiliary tanks for the mentioned aircrafts but an approximation would be quite enough.

Looking through Frost Kossler & Koos book on Dornier aircraft up to 1945, the range for the Do.11 is given as 960km at low level with a 1000kg load. The Do.13 is quoted without qualification simply as 1350km. Despite having a German wife, my command of the language is not perfect, but I do not see any mention of auxiliary tanks.

So far as the original single-engined Ju.52 is concerned, I have somewhere a copy of the manufacturer’s brochure (from an original in the National Aerospace Library at Farnborough). I don’t recall mention of auxialiary tanks in there either. I’ll try and find it to confirm. In the meantime, there is a useful description of the machine in Flight, February 27 1931, starting here:
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200202.html?search=Junkers%2052
with a useful table of range-vs-payload on the next page. The Ju.52/1m will be particularly difficult to get a single ‘range’ figure for, I suspect, as with only five or six built there were at least four different engines fitted.

Edit: Just looked more closely at the Flight article and found the bit that reads “The normal fuel capacity gives this machine a duration of 9.5 hours, but it is quite easy to add additional tanks in the wings or the floor of the cabin and to double this duration.”