But it wasn't dark
I dunno anything about piloting, I'm only here because the family talk about their airline inolvements so much I decided to try and understand the anger and passion a bit better, but I do know my astronomy.
The story didn't seem right. I looked up the ephemerides for McMurdo on September 12 because I thought there was no longer real darkness there.
The tables show the moon was at least nine tenths full and getting fuller and above the horizon all day and night.
The actual sunrise and sunset times in NZST were 0752 up and 1749 down.
Civil twilight began at 0613 and persisted after sunset to 1929.
Nautical twilight began at 0408 and persisted until 2137 that night.
Astronomical twilight (some visible light) lasted between the end of nautical twilight and its return next monring.
And the moon shone brightly all the while.
Seems to me a very odd choice of timing if they were after true darkness, as there wasn't any.
I did some time at Scott Base which is near McMurdo way back as a young chippy before moving back to Australia. There are times in summer when really dense fog and snow might make you wish you could see in the dark, if there was anything in it you might want to see, like a hut or a tractor.
But true darkness at high latitudes is elusive. Even in mid winter the moon will spend days continuously above the horizon, and at 78 degrees south there are very long periods of twilight before the sun returns and after it goes.
At this moment the sun is just above the horizon around 200 miles from the south pole for half the day. At the south pole it is just below it all day and the tip will appear above the horizon brigning 24 hours 'real' daylight this Sunday or shortly afterwards.
If these guys were serious about proving up true polar dark flight conditions they would have done this in June or July, and in the weeks when there was no moon.