The recent tragedy involving John F. Kennedy Jr. has generated speculation that the accident was caused by an attempt to fly VFR at night without sufficient visual references for a VFR-only pilot to safely control aircraft attitude. Even though the National Transportation Safety Board (NTSB) may not determine the probable cause of this accident for several months, such speculation suggests that a discussion about the challenges of VFR cross-country flight at night is appropriate and timely.
Federal Aviation Regulation 91.155, Basic VFR Weather Minimums, states that a VFR pilot flying below 10,000 feet (day or night) in controlled airspace must have a minimum flight visibility of three statute miles. Flight visibility, of course, is the forward visibility as observed by the pilot. It is not necessarily the same as that reported by ground stations.
Assume, for example, that a VFR pilot is over the middle of a 20-mile-wide body of water at night, and the nearest light sources are two airports. One is 10 miles ahead of the aircraft, and the other is 10 miles behind. Each reports a visibility of three miles in haze. Assume that the flight visibility at this time is also three miles. In this case, the pilot would be unable to see either of these airports. He would technically be in VFR conditions, but because there is nothing close enough for him to see, he would be unable to determine his flight visibility.
It is the VFR pilot's responsibility to determine that his flight visibility is at least three miles at all times. If the pilot is unable to do this, then he does not belong there. Such a pilot also would be unable to maintain the minimum required distance from clouds at such a time, because he would be unable to see them, either.
So much for the letter of the law.
The spirit and intent of Part 91 is to ensure that VFR pilots maintain sufficient visibility to safely control aircraft attitude without having to use instruments.
There are many nighttime occasions when a pilot might be operating in good visibility and yet be unable to see objects beyond the confines of his cockpit. This can occur not only when flying over water, but also over remote desert and mountainous regions of the western United States (or anywhere when flying above an undercast). Such a condition can be all the more hazardous when a high overcast obscures the sky.
The NTSB might eventually conclude that the probable cause of the Kennedy disaster was disorientation and loss of control as the result of having had insufficient visual references. If this happens, do not be surprised by a clamor for additional regulations, even though none are needed. The most feared recommendation from those who think that they know best would mandate an instrument rating for all night operations, which would be a tragedy unto itself. Many of our most cherished and memorable flights have been made safely at night without an instrument rating. Such a regulation also would seriously erode the utility of general aviation aircraft.
Regardless of what caused the Kennedy accident, speculation about it seems to indicate that flight training should place greater emphasis on the imperative need for VFR pilots to maintain visual reference to the ground or to a horizon during VFR night operations. If a pilot departs a shoreline or heads into the desert and discovers that these references do not exist, he or she should have been trained to recognize the need to reverse course immediately and return to those visual references that have been left behind. The pilot should be aware that flight into such conditions is no different than flying into a cloud, because the effect and the results can be the same.
In some cases, flying at night without sufficient references can be more hazardous than inadvertently flying into a cloud. Cloud penetration usually triggers a conditioned response bred of good training. The VFR pilot knows to reverse course and exit the cloud without hesitation.
Losing visual reference at night does not stimulate such decisiveness, because the loss often develops more gradually.
A pilot heading across the desert or a body of water might see only one or a few distant single-light sources that convey a sense of good visibility. Consequently, he or she might not immediately recognize the loss of needed visual references. Instead of making a one-eighty, he continues until vertigo, disorientation, and loss of control become increasingly likely.
Aiming for a single light (such as one emanating from a distant boat when over water) can be more dangerous than having no visual reference at all. If a pilot aims for and stares at such a light, it may soon appear to move from side to side in wide, irregular arcs, an illusion known as autokinetic motion. Lacking other visual references, a pilot's senses may interpret this apparent movement of light as a change in heading or attitude. Without realizing it, the pilot maneuvers the aircraft to keep the light positioned in the aircraft's windshield. In the meantime, the pilot's senses provide the erroneous sensation that the aircraft is on an even keel — even though it is not. The result can be vertigo and loss of control.
It appears, however, that problems related to VFR pilots flying at night can be avoided simply by understanding and heeding the intent of regulations already in place. It is simply a matter of watching where you're going.
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