Legal Briefing

Night flight fuel requirements

In this column, we have been reviewing the night flying requirements in the federal aviation regulations. We first looked at what "night" means for purposes of satisfying your night flying training requirements (see "Legal Briefing: Defining 'Night,'" November 2004 AOPA Flight Training). The FAR general definitions section states, "Night means 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."

We then examined the night flying recent experience requirements, which expect you to have made three takeoffs and landings to a full stop during a "night" time -- defined differently than in the general definition -- in the preceding 90 days to qualify as pilot in command of a night flight carrying passengers (see "Legal Briefing: Staying Night Current," December 2004 AOPA Flight Training).

This month, let's review the fuel requirements that you must meet to operate an aircraft on a night flight. FAR 91.151, Fuel requirements for flight in VFR conditions, states that:

(a) No person may begin a flight in an airplane under VFR conditions unless (considering wind and forecast weather conditions) there is enough fuel to fly to the first point of intended landing and, assuming normal cruising speed --
(1) During the day, to fly after that for at least 30 minutes; or
(2) At night, to fly after that for at least 45 minutes.

The fuel requirements for a flight in a rotorcraft under VFR conditions are the same for day or night, and they require that there is enough fuel to fly to the first point of intended landing and, assuming normal cruising speed, to fly after that for at least 20 more minutes. The fuel requirements for operating under IFR are the same for both day and nighttime flights. You must carry enough fuel to get to your destination, from your intended destination to an alternate destination if necessary, and assuming normal cruising speed, for 45 minutes longer if you are in an aircraft and 30 minutes longer if you are in a helicopter.

So, when preflight planning a night flight, you need to ensure that you are choosing your fuel stops so that you may expect to land with at least 45 minutes' worth of fuel. Your planning to have this extra amount of fuel in your tanks when you land must be based on calculations of fuel burn that consider the route of flight, weather conditions, weight and balance, and performance of the aircraft. Your preflight fuel planning should be evident in the information that you give when filing a flight plan, including the estimated time en route and the fuel on board, in hours and minutes. The requirements for extra fuel are considered to give you sufficient reserves in the event of an unexpected delay.

Note that compliance with the fuel requirements is based on what you plan before you take off; the FAR does not require that you actually land with the minimum amount of extra fuel. And, remember, the night VFR fuel requirements are minimums, as prescribed by the regulations -- which are, as a whole, nothing more than a set of minimum standards. You may always choose to exceed those minimums. The night flight fuel reserve specified in the regulation is to increase the minimum margin of safety provided by the FAR requirements for day flights. If you choose to exceed those minimums, you give yourself a greater safety margin. You may feel the need to carry even more fuel than required if forecast weather conditions could change, if you are inexperienced with the fuel burn or performance of the aircraft, or if your proficiency in nighttime navigational skills isn't what it could be.

Night is a beautiful time to fly, but night does not present the ideal environment for executing an engine-out landing. Plan properly by complying with the FARs to stay legal and adding any additional safety margins that make sense under the circumstances.

Kathy Yodice is an attorney with Yodice Associates in Washington, D.C., which provides legal counsel to AOPA and administers AOPA's legal services plan. She is an instrument-rated private pilot.