The nights got shorter

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The nights got shorter

Post by hum »

SERA has introduced Night VFR, but also changedthe way 'end of VFR time' is calculatred in Ireland - the nights have got shorter!

The 'old' SI 72 'Rules of the air' defined night thus:

“night” means the hours between the end of evening civil twilight and the beginning of
morning civil twilight, or such other period between sunset and sunrise as may be specified
by the appropriate authority. In or over the State, “night” shall be deemed to be, during the
period beginning on the 1st day of April, and ending on the 30th day of September, the
time between half an hour after sunset and half an hour before sunrise, and during the
remainder of the year, the time between sunset and sunrise, and for the purpose of this
definition sunset shall be determined at surface level;

Since SERA recently came in we no longer have a seasonal changeover & night is now from the end of evening civil twilight to the beginning of morning civil twilight.

Practical implications I see:

Its now easier to figure out theoretical start/end of VFR times - and its the same procedure all over Europe.

Beware - most GPS units give sunrise/sunset times, I recommend using an app to get start/end of civil twilight.

It is now 'legal' to fly under VFR for considerably longer on any given day.

EG: On 21 Dec in typical Irish Latitudes one gets an 'extra' 1h:26m under SERA compared to the old SI 72 while On 21 June we now have an 'extra' 45 min.

Beware, however, staying airborne until the end of civil twilight in Ireland in winter - especially on an overcast dull day, would not be a good idea unless one is night qualified. :)

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