What is night?
Regulations concerning night flight can be confusing
Night is one of my favorite times to fly, as I’m often returning home from an adventure-filled day and the typically smooth air makes the flight feel effortless all the way to a gentle landing on the runway. And avoiding other aircraft is easier since it’s less difficult to see them during the night. Well, that’s what I used to think. But conversations with practical exam candidates have me reconsidering that.
The conversation usually goes like this: I let my candidate imagine that, during the walkaround, he finds the red light on the left wing tip is burned out. “Will this affect the cross-country we’ve planned today?” “Well, we need to turn position lights on by end of civil twilight….No wait, as long as we land before an hour following sunset, we should be fine.”
Then I ask about the privilege of carrying passengers at “night” and most candidates say, correctly, that they need to have made at least three takeoffs and landings to a full stop during the period between an hour following sunset to an hour before sunrise within the preceding 90 days. I ask, “Why do you think the FAA has you wait that long?” “Well, because it’s typically good and dark by then.” I respond with, “Then why would the FAA want you to wait that long to turn your lights on?” and I get to see the “aha” moment, “Oh, that’s why they need to come on at sunset!”
To be fair, regulations concerning night flight can be awfully confusing, so let’s review some of the pertinent ideas. Twilight is the period when the sun is below the horizon but still illuminates the atmosphere to some extent. Civil twilight occurs between sunset and when the sun falls to six degrees below the horizon. The National Weather Service site explains that, during civil twilight, the horizon and terrestrial objects can be discerned and that artificial light is often not necessary. In nautical twilight, which ends when the sun is 12 degrees below the horizon, outlines of terrestrial objects may be discerned but artificial light becomes necessary.
The FAA defines night as the time between the end of evening civil twilight and the start of morning civil twilight, and any flight during that window may be appropriately logged as night. In Sewanee, Tennessee, civil twilight usually ends around 30 minutes after sunset and starts around 30 minutes before sunrise. But that can vary considerably based on location and time of year. ForeFlight now showcases these times under Solar Information for each airport.
My question about flying passengers at night was vague. FAR 61.57 requires pilots to make those recent operations between one hour after sunset to an hour before sunrise to carry passengers during that same period. Conceivably, a pilot might not have flown at night in years but land with passengers 59 minutes after sunset and still follow the rules—legal but hardly safe. Appropriate personal minimums can include flying with passengers between sunrise and sunset if recent “night” experience is lacking.
Night operations present an opportunity for instructors to engage in a rich discussion with students. Instead of merely memorizing regulations, ask students to explain why they make sense. And develop personal minimums when they don’t.
Catherine Cavagnaro teaches aerobatics at Franklin County Airport and is the Gaston Swindell Bruton Professor of Mathematics at Sewanee: The University of the South.
