NavList:

1.   I think we have to accept that publicity photo-calls are just that and probably nothing like the situation after the reporter’s left, so it’s probably not worth getting too hot under the collar about what we see in newspapers.  They’re there to publicise the organisation and sell newspapers, not to teach the public celestial.

2.  On shooting though glass/plastic, we have to remember that aviators have been shooting though plastic/glass since the late 1930s.  It all depends upon the quality of the plastic/glass.  No doubt our respective governments pay huge sums for perfectly parallel glass for use in periscopic sextants including magic heating film.  It was virtually impossible to blow or pull a perfectly parallel Perspex astrodome, so they issued standard dome refraction tables instead, which might or might not fit the dome on your aeroplane.

3.  On celestial being a back-up for loss of GNSS.  Unless the USN has a device that can guarantee clear skies at all times, celestial is a pretty unreliable back-up.  This leads me back to my original suggestion that this is as much to do with maintaining standards, engendering confidence in tyro navigating officers, and inculcating a strong sense of the traditions of the USN from John Barry and John Paul Jones onwards as with GNSS loss.  The obvious short-term replacement for temporary loss of GNSS is SINS or eLoran, if available, and if all else fails, there’s dead-reckoning. DaveP