NavList:

Geoffrey, you wrote:
"I find it curious that all the photos of sightings being taken with the Plath/Coutinho sextant on the Graf Zeppelin (that I have seen) show the index arm right back around the zero degrees altitude point "

Yes indeed. I noticed that, too. But if you imagine yourself aboard the zeppelin, there is a simple explanation. As seen from the gondola, or control cab, the rest of the airship is a great grey cloud obscuring nearly all of the sky above roughly twenty degrees of altitude. So if you shoot altitudes from the control cab, they will necessarily be low altitudes. The photos then make great sense.

But wait... We cannot conclude from this logic that sextant sights were always taken at low altitudes. That's just the best place for photography of the navigator at work. Those giant airships also had observing locations up top, accessible by long ladders in flight. A photographer could not follow the navigator up there easily. The relative frequency of sights from the control cab versus sights from the lookout positions atop the airships can only be judged from the actual logbooks. Those logbooks exist. So right there is a project for someone with the time to do the work that would likely lead to a definitive answer.

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