It is commonly taught that there are three definitions of “night” that pilots need to be concerned with. They involve logging flight time, carrying passengers, and periods for required illumination of aircraft lighting. There aren’t three definitions: there is only one. Let’s take a three-minute trip through the wonderful world of Federal Aviation Regulations (FARs).
The Definition Of Night
We find definitions in the Code of Federal Regulations (CFR) typically in the first section of the part applicable. Night is defined early in Title 14: Aeronautics and Space.
14 CFR 1.1: General Definitions
Night means the time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the Air Almanac, converted to local time.
That’s all. That is what night is. There are no other definitions.
The confusion comes from our personal concept of night versus the actual definition. So, we tend to lump the following time periods in their respective regulations as “other definitions of night.”
The first such regulation we encounter is 14 CFR 61.57: Recent Flight Experience, Pilot In Command. In this regulation we find the confusing title of “Night takeoff and landing experience” in (b):
14 CFR 61.57(b): Night Takeoff And Landing Experience
Except as provided in paragraph (e) of this section, no person may act as pilot in command of an aircraft carrying passengers during the period beginning 1 hour after sunset and ending 1 hour before sunrise, unless within the preceding 90 days that person has made at least three takeoffs and three landings to a full stop during the period beginning 1 hour after sunset and ending 1 hour before sunrise, and….
Notice how the actual text of the regulation describes the “period beginning 1 hour after sunset and ending 1 hour before sunrise” as the requirement for staying current to carry passengers during that time frame. It doesn’t say that night IS this period, but the title of the regulation confuses us by using the word “night.” As a side note, this same time period is used for logging Night Vision Goggle Operations (NVGOs) per 14 CFR 61.1.
A similar regulation for commercial ops in 14 CFR 135.247(a)(2) did not use the word “night,” and instead kept just the “beginning 1 hour after sunset and ending 1 hour before sunrise” in tact.
The second confusing regulation deals with the required operation of aircraft lighting.
14 CFR 91.209: Aircraft Lights
No person may: (a) During the period from sunset to sunrise (or, in Alaska, during the period a prominent unlighted object cannot be seen from a distance of 3 statute miles or the sun is more than 6 degrees below the horizon)—(1) Operate an aircraft unless it has lighted position lights…
In this regulation we are only talking about having position lights illuminated during sunset to sunrise (or the Alaska time period exception). Again, it doesn’t refer to “night.”
Lastly, for logging night flight time we see the regulation actually use the word “night,” and thus referring to the definition we discussed from 14 CFR 1.1.
14 CFR 61.51 Pilot Logbooks
(b) For the purposes of meeting the requirements of paragraph (a) of this section, each person must enter the following information for each flight or lesson logged….
(3) Conditions of flight—
(i) Day or night.
So there you have it. There is only one definition of “night,” but during periods we commonly conceptualize as night there may be regulations that apply to our operation, such as passenger carrying currency and knowing when to turn on aircraft lighting systems. This may seem like needless semantics, but it’s important to pay attention to the detail when concerned with regulations. Understanding the regulations correctly may save our pilot certificate one day.
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