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A partial or total eclipse is as dark as twilight, but only for a short period. Does it count as night flying for regulatory purposes?

I'm looking for a UK answer, but information about the US is interesting too.

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  • $\begingroup$ You are overestimating how dark it gets in an eclipse. sure, if you're flying straight through the umbra, it's quite dark, but that's at most 260 km wide. Even a cessna flies through that in less than an hour, not even taking into account that the umbra itself also moves. The penumbra, the area around it, is only as dark as twilight while the eclipse is well over 90% coverage. outside of that small area, you'd be struggling to even notice the eclipse. $\endgroup$ – Nzall Mar 21 '15 at 22:33
  • $\begingroup$ @NateKerkhofs You are underestimating how recent my experience of an eclipse is. I wouldn't really expect it to count as a night flight in a log book, but I could believe it might activate LVP or some safety rules that normally only apply at night. $\endgroup$ – Dan Hulme Mar 21 '15 at 23:15
  • $\begingroup$ @Nzall: A typical solar eclipse "moves" at roughly Mach 2. (sunearthday.nasa.gov/2006/faq.php), and is usually over in 2-3 minutes. The speed of a Cessna is not even relevant. $\endgroup$ – abelenky Apr 26 '17 at 22:48
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No: that does not count as night flying.


The CAA defines "Night" (Air Navigation Order, Article 129) as:

‘Night’ means the time from half an hour after sunset until half an hour before sunrise (both times inclusive), sunset and sunrise being determined at surface level;

Similarly, the FAA's definition (FAR 1.1) is:

The time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the American Air Almanac, converted to local time.

Since an eclipse is neither a sunset or sunrise, nor does it happen between evenings and mornings, it does not fit the definition of "Night" for legal purposes.

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  • $\begingroup$ More definitions of night flying used by the FAA: aopa.org/News-and-Video/All-News/2005/October/11/… $\endgroup$ – Maverick283 Mar 21 '15 at 11:09
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    $\begingroup$ This. However this is a neat place to note the difference between "rules" and "prudence". Obviously if you are going to fly (or more importantly, LAND) during the depths of an eclipse it would behoove you to consider all the elements that go into a successful night flight. Seems like an ultra-rare situation but if you're doing it on purpose, do it right! Remember you can always ask the tower to turn on the runway lights or some fields automate them with radio clicks - see your airport guide. $\endgroup$ – Ezekiel Kruglick Mar 23 '15 at 23:53

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