In one respect, I'm afraid of the dark. I live in the mid-Atlantic region, and I fly single-engine fixed-wing and rotary wing aircraft. Here, the terrain undulates, and flat fields often are the exception rather than the rule. Consequently, I get even more cautious whenever I fly after sunset.
After the requirements for a pilot certificate have been met, how many of us seek dual instruction at night? How often do we practice groping for the runway with a burned-out landing light, inoperative panel lights, or while handling an engine failure? Aside from finishing that last hour of a cross-country flight that sometimes ends with a single night landing, or the three times around every 90 days, how many of us take off on a night cross-country? Other than the freight dogs and a few pilots who prefer the night shift, not a great many of us are in that group. And how many of the roughly half of all pilots who aren't instrument-rated know what it feels like to be deprived of most of their familiar visual references, even though the air is crystal clear?
Night accidents are actually fewer in raw numbers and on an hours-flown basis than daytime--but night accidents are more likely to be fatal than those that take place in daylight. According to the AOPA Air Safety Foundation's 2007 Nall Report, there were 7.1 accidents per 100,000 flight hours in daylight compared to 6.6 at night.
Night accidents were fatal, however, more than one-third of the time (34.6 percent) compared to daytime accidents, which involved fatalities 19.2 percent of the time. Night accidents in instrument weather conditions had the worst outcomes with nearly three-quarters (74 percent) resulting in fatalities.
What are the hazards associated with flying at night? In no particular order, first of all, the horizon (and the ground) is harder to see. For pilots flying by visual references, it's easier to get disoriented or simply lost. Most of us are not night owls, and we're more tired at night. And of course, the biggest excuse for blundering into clouds is that we can't see a cloud coming anywhere near as well as we can during the day, so an inadvertent encounter with instrument meteorological conditions can happen.
Airports may be a bit harder to find. Without as many visual cues at night, most new pilots approach the runway too steeply, and too fast. This is the realm of the dreaded black hole. At night, optical illusions abound. During cruise, scattered ground lights can appear to be stars, causing a pilot to lower the nose and descend. Unlit terrain with an overcast or dark sky beyond can make the horizon appear to be lower than it really is. Sloping clouds can cause a pilot to enter an unusual attitude.
Illusions can arise from the eyes, such as an after-image from a bright light, or the brain, when one misinterprets a false horizon. They can also occur from the innocent cooperation between the eyes and the brain, such as with nystagmus, the involuntary and rapid oscillatory movements made by the eyes when the body experiences vertigo, or autokinesis, which are small, involuntary but normal motions of our eyes that can cause an object to seemingly move in irregular arcs.
Miscues can also arise from within your ears: in this case, the otoliths in the cochlear canals--our balance organs. Each ear has a pair of them, one being vertical, and the other horizontal. Each contains otoliths, which are small crystals attached to the free ends of sensory hairs that are in turn connected to nerve cells on the cochlear canals' walls. When our heads are tilted back, the hairs bend, and certain nerves send a "tilt" message to the brain. The problem is that forward acceleration, such as taking off on a dark night over featureless terrain, can cause the otoliths to convey that tilt message, particularly when there isn't any visual information to override it after the takeoff roll ends and you climb away from the airport.
Our neck muscles tell our brain that our head has not tilted back and that we must be climbing quite steeply, so we judiciously push forward on the stick or yoke (which only adds to the acceleration, of course, making things worse). This is known as the somatogravic or false climb illusion. Flying VX or VY is probably the safest during the initial stages of a night takeoff; make good use of the attitude indicator and vertical speed indicator.
Just when the demands of flying a nighttime trip and descending into an unfamiliar airport pattern are almost over, it can get worse. The next greatest fear, believe it or not, is the flare and touchdown. Most of us seem to know quite well that our peripheral visual cues won't be around to help us sort through this phase of flight (or if we don't, one time is enough to convince us). And most of us rely on what we see from the landing light up front in order to judge our sink rate. The FAA's Airplane Flying Handbook suggests watching until the landing lights reflect on the runway; when you see tire marks or other details on the runway surface, start the roundout and gradually reduce power to idle.
What else can we do to improve nighttime flying safety?
If you can't see it and identify it, don't trust it. Avoid long straight-in approaches at night, as tempting and available as they may be. Descend from higher up, keeping a safe gliding distance if you prefer, until you're at a normal pattern altitude. This is especially true if the destination airport is surrounded by higher terrain. If any lights on the ground suddenly twinkle or go out, climb! It might've been because they disappeared behind a hill. If you don't like the looks of a 3-degree glide path to any part of a runway, fly a tighter pattern. Whenever available, use the VASI or PAPI and be sure to fly no lower than "red over white." Always be absolutely positive that what you think is an airport really is one!
Altitude is your friend. As far as that perceived fear, my own solution is flying higher at night. Your terrain and obstacle clearance should be all the greater, and a side benefit is that your radio reception will be, too (especially useful, should you need it).
Pay attention to the time of the month. Whenever you're planning a long trip that is unlikely to end before the day does, try to do it as close to a full moon as possible. Obviously this would exclude nondiscretionary mission-critical types of flying.
Seeing forever. For nighttime newbies, having great visibility will also make life a whole lot easier. The five-mile legal minimum is better off doubled.
When over-flying airports en route, click on the pilot controlled lighting. It may be wasting some electrons, but a lit airport makes a great landmark, and if you should suddenly need it, your own personal marquee would then already be waiting for you.
Speaking of lights, light your own. You'll have a few seconds' more advance notice for any clouds lying in wait, and other night fliers (birds included) will see you better. (If you're flying through a light snow shower, however, you might feel like you're doing Warp Five, so it isn't always the right thing to do.)
Jeff Pardo is an aviation writer in Maryland with a commercial pilot certificate for airplanes, and instrument, helicopter, and glider ratings. He has logged about 1,300 hours since 1989. Pardo has also flown for the Civil Air Patrol.
Want to know more?Links to additional resources about the topics discussed in this article are available at AOPA Flight Training Online.
By Jeff Pardo Photography by Mike Fizer
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