night ops: enjoy, with respect

March 12, 2019

While there’s nothing inherently dangerous about flying at night, a night flight can quickly turn hazardous if the pilot is not adequately prepared. Capt. LeRoy Cook provides some preflight planning tips to avoid surprises during night flight

There’s no difference between flying in daylight and flying at night – other than not being able to see. So go the words of wisdom imparted by training instructors, and they’re essentially right. The airplane doesn’t know or care that its pilot is visually impaired during the hours of darkness. It performs and responds just as it does in daytime. However, we, as the human pilot, are the weakest link in the conduct of successful night flight. Accordingly, we must respect our limitations, and they are manifestly increased when we fly in the dark.

Statistically, the risk of a fatal accident increases at night, despite the relatively smaller number of flights undertaken during darkness. Simply put, night operations are less forgiving of an error than it would be in the case when the same mistake was made in daylight. While the same weather is present as in daytime, obstruction hazards and runway lengths are not altered, and the equipment is no more prone to failure, pilots don’t cope as well when faced with a challenge during darkness.

What’s the Big Deal?

The fact is, we are ill-equipped for operating an airplane in the dark. The human eye has limited acuity for night vision, and we require constant visual references to maintain equilibrium. We are diurnal animals, not nocturnal ones, and our body doesn’t perform well when it would rather be sleeping. To make up for these shortcomings, we need adequate lighting, solid orientation to discern up-versus-down and a willingness to restrict ourselves from continuing into dangerous conditions.

Face it, night flying is, for all intents and purposes, instrument flying. Even under the best night VMC, we can encounter areas where ground lights are scarce and a horizon may be difficult to see. A clearance for a night visual approach should be accepted only under the most familiar, well-illuminated circumstances. Similarly, circling approaches are best avoided after breaking out at night. Stick to a straight-in landing, with glidepath guidance.

Does having a full moon help? While the moon-lit landscape can be a comforting simulation of daylight, bright moonlight can wipe out a dim star canopy and produce blinding glare in haze. Do not expect to be able to avoid high terrain visually by moonlight. Even a full moon doesn’t always provide enough visible detail to discern flat ground from steeply-rising terrain. Still, the Lunar orb is a comforting reassurance that the weather’s clear.

Fly no airplane at night unless you’re familiar with its cockpit layout and you have full confidence in all its working parts. You might tolerate a glitchy radio or an intermittent annunciator warning in daylight, but at night you want everything to be working perfectly. Know where everything is and be able to find it by touch; military pilots used to be given a “blindfold cockpit check” as part of their training, demonstrating their knowledge of the switches and controls.

Most importantly, carry multiple flashlights when flying at night. I can guarantee that you will have an electrical failure if you fail to do so; I’ve burned up rheostats, broken generators and lost instrument lights, and most of the time these occurred when I hadn’t kept a freshly-charged flashlight on board. A large D-cell flashlight and a pocket penlight, fitted with red lenses, can make a big difference when something breaks. Why red lighting? Because the eye’s rod cells, which provide most of our night vision, work well in the red end of the spectrum but are restricted under strong white light, leaving us with only the daylight-favoring cone cells until the rods recover. Limit the intensity of any necessary white lighting you use.

Be More Cautious at Night

Begin with a careful preflight; you should be in the habit of checking all of the airplane’s lights, even in daytime, because you never know when an unexpected headwind or delayed departure will require a landing after dark. If on a poorly-lit ramp, dig out the flashlight to peer into wheel wells, check under cowlings, and look at control hinges.

Take your time during taxi and run-up. Moving around at night requires a bit more deliberant care in taxi speed, to maintain orientation and centerline alignment. Do not program your FMS and set up frequencies while moving; do it at the ramp before taxi or stop and set the brakes to perform these chores. When standing stationary, be alert for unnoticed creeping toward the edge of the pavement. Avoid throwing on strobes and other bright lights before taking the runway, out of consideration for the pilots around you. But if asked to “line up and wait”, have every light on to show that the runway is occupied.

As you sit in position, take a second to note the appearance of the runway lights. They will be aligned just below your shoulders, thus when you’re in the landing flare you’ll want to see them just a little below where they are in your static position. Notice that the two lines of runway lights make evenly-sloped angles converging on the red lights at the departure end. Do not allow one line of lights to be straighter and the opposite one to form a larger angle; that means you’re off the centerline. Don’t crowd the edge lights, because they are ten feet or so out in the grass.

Advance power smoothly and track the centerline, planning to rotate to the recommended pitch attitude and lift off with the target V-speed in hand to carry the aircraft into a brisk climb. Upon breaking ground, use the PFD to hold a safe pitch angle and keep the wings level. The initial climb is most likely to be taking place in a “black hole” until you gain enough altitude to see a landscape of ground lights.

Once you’re safely away from the hazards of ground obstructions, keep any eye out for lighted landmarks to guide your departure, supplementing the charted departure procedure or vectors. Use the compass heading to settle arguments in your situational analysis, and take a look back at the airport to see how it appears among the lightscape surrounding it. Roadways filled with car lights make good visual references, small towns in the blackness of open country can provide orientation, and those tower obstructions that you can barely see in daylight suddenly become valuable location identifiers when their lights show up at night. The relationships of airport beacons to their accompanying cities provide excellent verification that you’re looking at the correct landing spot.

Remember that you cannot judge altitude in the dark; you must pay attention to your altimeter and know your safe altitude for your area. If you are approaching higher terrain and you begin to see the nearest lights disappearing from view, take it as a warning that you are not going to clear the upcoming ridge.

One must keep a closer watch on the weather situation when flying at night, because of evening cooling and more limited alternatives if forced to divert late in the day. Monitor ASOS and ATIS broadcasts to make sure weather isn’t moving into your route, and note the spread between temperature and dew point. When the gap closes to two or three degrees and any moisture is available to saturate the atmosphere, ground fog will begin to form, starting in the coolest low places, which is often where airports are located. Maintain a healthy fuel reserve, in case you need to deviate to an alternate.

Consider own your state when flying at night. Because a higher level of attention to detail is needed for night flying, avoid flying fatigued. It’s one thing to arrive back at home base an hour or so after sunset, and quite another to conclude a meeting after 10 p.m. and try to get everyone home in the wee hours of the morning. If you’ve been awake for 20 hours you have no business trying to fly at night. Even the best-crewed aircraft won’t make up for a lack of rest.

Landing Safely

Are you quite sure you’re lined up on the correct airport? At night, all lighted runways look about the same, which is the reason most of the inadvertent wrong-airport landings take place during darkness. This is another reason to fly a charted instrument approach procedure, even if visual conditions prevail. Be alert for indications that something doesn’t look right; don’t assume there’s a strong crosswind skewing your final approach heading or you must descend quickly to land on first set of lights you see. You might be attempting to land at the wrong airport.

More and more airports are saving pennies by the use of pilot-activated lighting, so you may not find a lighted runway welcoming you as you arrive at your destination. Do your homework when planning the flight, making sure you know how to activate the lighting? In most cases, flicking the mike button seven times on the published frequency will get the lights turned on. If they are already on, they may be in a 15-minute activation cycle triggered by another pilot. Be ready to re-activate the lights if they go out while you’re on final.

Naturally, you will have checked to see if the airport has special night operations requirements. While you are carefully following an obstacle-avoiding arrival, with electronic guidance, don’t neglect to maintain vigilance for other aircraft. Airplanes are actually easier to see at night as their anti-collision and position lights move across the blackness. Traffic below you may be harder to spot against the ground lights. Beware of a steady, motionless light in your field of vision; it may be converging traffic.

Don’t make extreme or rapid maneuvers in the dark; avoid steep banks, and use your altimeter and heading in indications to help set up the legs of the approach path. Always double-check your altitude as you turn onto final approach; be no less than 500 feet AGL at that point, and add some power to stabilize descent if you’re getting close to the minimum. Again, you can’t judge altitude at night by looking out the window. Watch for the VASI lights and stay precisely on their red/white beams.

Depth perception can be tricky as you focus on the bright spots illuminated by the landing lights, and you can encounter “target fixation” as you approach the ground, tempting you to fly right into the surface without flaring. To avoid this, utilize the cockpit-height relationship to the runway edge lights, remembering your pre-departure sight picture, to supplement the landing lights. On the other hand, good landing light coverage helps see the tire marks and centerline to better manage crosswind drift, so use all the lights you have available.

The challenge of operating an airplane in the dark carries the reward of knowing you’re utilizing a valuable business asset to its maximum potential. Just be aware of the human factors and respect them by operating with higher safety standards at night.