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Joshua/Patrick

It was only when I looked at Patrick’s work that I realised the significance of the closeness of Dec Sun to latitude. The Sun rises gradually from the east, whips over the top, and descends slowly to the west. Don’t tell the Boy Scouts Association; they’ll have nothing left to teach.

Patrick you said: “Those LOPs are way too close to parallel to be of any real use.”. I disagree. Nothing is totally useless. They’re not much use along track, but they remain very useful across track. They show you’re drifting east of heading. If you were to MPP your 03.33UT fix on 2nd Aug with your worked up DR position for the same time (even if you just took the half-way point) it would give you a best estimate of track. So, you would know which side to look for the island. If by the time your DR position said you were abeam you’d seen nothing, you’d know which way to turn. Kind of quasi-Chichester.
When we crossed the Atlantic east to west in the Vulcan in the 1970s, it was usually around local noon most of the way across (480kts TAS). Each hour, I’d take a sun line and heading check, and the plotter would mark his DR position. Then we’d draw a line from the DR position perpendicular to the Sun line. There were values laid down for the ratio to split the line into to get a revised DR position, but sometimes we’d just dangle a pencil over the line. I knew how well the three one-minute shots had gone, and the Plotter knew how well the equipment was working. Our brainwaves would merge and the pencil would descend to mark our new MPP, which we’d reset the equipment to (but don’t tell our Government). When we returned west to east, it was invariably nighttime and we did hourly seven one-minute shot sandwich fixes (2,3,2).  DaveP