NavList:

David,

re Das Boot.

You wrote "Good time for a dawn or sunset compass check, but shouldn't Hs be about 8', not 25° 43.3'.  Also, unless the lookout with the chip bag on his head's changed places, the Sun's azimuth's changed through about 180° in 30 seconds....." 

I noticed that too, but seem to remember the original German TV series clip of this was longer, more detailed and involved a 2 body fix ( dawn twilight) of Jupiter and Saturn? I'm trying to find it. I've just re-checked the excellent original book by Lothaaar-Gunther Buchheim, page 74-75 describes this Jupiter/Saturn dawn fix. Gives Hs for Saturn 22°35'. this gives him 1 "baseline" but he needs 2 (presumably means LOP?)  then a few minutes later Jupiter Hs 22°27'. He then describes the navigator working out the sights with logs, cosines and sines.He then says "..with all the technical perfection here in the boat, it is really astounding that you still use the sextant and stars to find the ships position." The navigator replies, " how else could I do it?"

All good stuff. The book and film definitely one of the best "anti-war" war dramas with respect to the ultimate  futility of it all, despite all the remarkable human bravery etc. Good on technology as well eg. the British devilish inventions of  Asdic for the sinister ,unseen destroyers lurking   above and the new fangled miniturised airborne radar (courtesy the new cavity magnetron)  in the bombers that suddenly appear from no-where.

Francis