Flying in the Dark

Managing the risks Acknowledging the increased levels of risk involved in night flying and knowing as much as you can By Dale Wilson about their nature are the first steps in successfully managing them.

16 • www.nafinet.org you’re like me, you probably five of them occurred in good VFR Controlled Flight Into Terrain enjoy flying at night. The ride weather conditions during the hours of Unfortunately, it’s also easier to Ifis often smoother, the radio is darkness (or at dusk). The pilots in two inadvertently fly into unseen terrain usually quieter, and as one of my in- of these accidents reported they were at night. This is what claimed the lives structors from the Midwest said, “It’s unable to see the other aircraft until of eight members of country singer just plain purdy.” But it’s not without their landing lights had illuminated Reba McEntire’s band and two flight risk. Driving an automobile at night them during the landing rollout. crew members. While waiting for an increases the risk of a fatal accident IFR clearance below the San Diego TCA and so does flying an aircraft — The Dark-Night Takeoff Accident (now called Class B airspace), the crew according to the AOPA Air Safety An equally serious accident can of the Hawker-Siddeley 125 flew under Foundation — by almost a factor of occur after liftoff, especially on dark controlled flight into mountainous ter- three. As an instructor you may not nights (i.e., no moon illumination and/ rain (CFIT) near Brown Field airport. be fully aware of all of the hidden or overcast sky and few if any surface I talked to someone who was in the dangers that lurk in the dark, but if lights ahead of the aircraft). They even vicinity on the night of the accident; he you want your students to know how have a name for it: the dark-night said the weather was CAVU, but it was to effectively manage these unseen takeoff accident. In the absence of very dark. The official accident report threats, you owe it both to yourself adequate outside visual references our indicates a clear moonless night with and to them to find out. somatosensory and vestibular sensa- a visibility of 10 miles. Unfortunately, Some of the hazards unique to tions create the illusion of a nose-up the occupants of an air ambulance piloting when the sun goes down can attitude when accelerating on climb- Learjet 35 suffered the same fate in manifest themselves even before you out after takeoff or during a go-around almost the same location 13 years later. get airborne. For example, the loss (Figure 1). This has resulted in tragedy While waiting for an IFR clearance and of optic flow in our peripheral vision as pilots, in response to these false maintaining VFR flight below a cloud often causes us to taxi too fast. It’s sensations, have unknowingly pushed deck in the dark, the aircraft crashed also easier to get lost while navigating their aircraft right into the ground. This within 1.5 miles of the HS-125 crash on the apron at night — especially at false climb illusion was specifically cited site, killing all on board. an unfamiliar airport, increasing the as a factor in a dark-night takeoff ac- possibility of departing from the wrong cident involving a Part 135 cargo flight Approach and Landing runway or even from a taxiway. A 2007 in Kamuela, Hawaii, that claimed the Accident statistics make it clear that study discovered more than 600 reports life of the ATP-certificated pilot. More compared to the other phases of flight, of wrong runway, or attempted wrong recently, an 18,000-hour commercial pi- the final approach and landing pose the runway, takeoffs in the United States lot died when his Beechcraft Baron G58 greatest risk. Even though they occupy over a recent 25-year period. A tragic impacted the waters of Lake Erie after less than 5 percent of total flight time, example of this involved a Comair re- a night departure from a lakeshore more than a third of the world’s fatal gional jet at Blue Grass Airport in Lex- airport in Cleveland, and a commercial airline accidents occur during these ington, Kentucky. Good visual meteo- pilot flying a Cessna 340 lost his life in segments of flight. A United Kingdom rological conditions (VMC) prevailed, a dark-night takeoff accident in Bishop, study found that 40 percent of fatal ap- but it was dark that early morning in California — the sky was clear with 10 proach and landing accidents occurred August, and the moon was below the miles’ visibility. at night, and a worldwide study of com- horizon. This may have contributed to mercial CFIT accidents found that half the crew’s misidentification of Runway VFR Into IMC took place in the dark with 70 percent 26 for Runway 22. Unfortunately, they You and your students should be of those occurring during the approach attempted a takeoff and ran off the end aware of two major threats that arise and landing. of this runway — which was half as during the en route portion of flight long (only 3,500 feet) as their intended — namely the inability to adequately Visual Landing Illusions runway — impacting the airport pe- detect weather or terrain in the dark. Elevated risk levels while landing rimeter fence and terrain, and killing all Attempted VFR flight into instrument in VMC at night are often due to the but one of the 50 people on board. meteorological conditions (IMC) is a increased probability of experiencing major killer in aviation. Statistics indi- a visual landing illusion on final ap- Runway Incursions cate the odds of experiencing such an proach. These have fooled many pilots Confusion while operating on the accident increase by more than a factor into thinking they were either too high apron increases the risk of a runway of three when you’re navigating in the or low on the approach. Especially incursion. Of the six fatal runway dark; it’s simply harder to see adverse hazardous are illusions that cause us to incursion accidents involving major and weather at night. conduct an unsafe low approach result- regional U.S. airlines during the 1990s, ing in a hard landing near the runway January 2012 • 17 The accident record clearly indicates the probability of flying into adverse weather or terrain, crashing short of the runway while on the approach, or experiencing a dark-night takeoff ac- cident rises significantly at night. Also, consider the consequences of these types of accidents: nearly all CFIT (whether en route or on the approach), VFR flight into IMC, and dark-night takeoff accidents involve fatalities. In response to a question about the safety of night flying, a pilot of a Cessna 210 stated that flying at night “was no different than flying in the daytime.” threshold or, at worst, a fatal CFIT acci- the black-hole illusion. Relying solely He died that evening in a typical dark- dent short of the runway. For example, on outside visual references when night takeoff accident. It appears he since we usually judge our approach conducting an approach in black-hole was unaware of the old adage that says, angle by the familiar trapezoidal image conditions inevitably leads to a danger- “Flying at night is no different than the runway shape casts on the retinas ously low approach and possible CFIT flying in the day — except you can’t see of our eyes, we will experience an illu- accident short of the runway. anything!” sion of excess height when conducting Analogous to relativity theory, the Acknowledging the increased levels an approach to an up-sloped runway pull of the black hole has left many of risk involved in night flying, and — especially in conditions of limited pilots unable to escape its grasp. The knowing as much as you can about their visual cues such as at night — causing most likely cause of this deadly threat nature are the first steps in successfully us to conduct an approach that is too was discovered by Boeing research managing them. Here are additional low (Figure 2). Similarly, an approach to scientists during a series of simulation strategies for you and your students to a smaller runway — especially one that studies in the late 1960s. They conclud- minimize the risks: has the same proportions or length- ed that rather than maintaining a con- to-width ratio (L/W) as the runway(s) stant descent angle, pilots who conduct 1. Don’t Believe Everything You See we’re used to — or to a runway that is visual approaches attempt to maintain Understand that what you see is not longer or narrower (i.e., greater L/W) a constant visual angle between the always what you get. Awareness of an than we are accustomed to also creates runway threshold and runway-end illusion doesn’t immunize you from a height illusion causing us to respond lights (or ground lights beyond). This being deceived by one. A CFI and his by flying too low ( ). These illusions are results in a curved approach path student and passenger were lucky to caused by a common malady known bringing the aircraft dangerously low land safely after striking trees on final as the ‘home-drome syndrome,’ where on the approach (Figure 4). This illusion approach during a training flight in the home-base aerodrome is so indel- recently fooled the crew of a Federal dark-night conditions. According to the ibly etched into our perceptual memory Express Boeing 727 while approaching Aviation Safety Reporting System re- that we misperceive other runways as Runway 09 at Tallahassee Regional Air- port, the instructor carefully explained similar to our own. It’s especially strong port in Florida. The aircraft struck trees the phenomenon of the black-hole illu- where there’s little or no surround- on short final and crashed short of the sion to the student beforehand — that ing context that would give cues to a runway, seriously injuring three crew is why he, rather than the student, flew runway’s actual size — such as during members aboard. The NTSB report indi- the approach. He reported that it was the hours of darkness — and is more cates the approach was conducted over ironic that he was “consciously aware pronounced in low-time pilots (e.g., unlighted terrain in VFR conditions at of the illusion problem and trying to students) who lack real-time experience night, resulting in black-hole conditions correct for it” when they hit the trees! conducting approaches to a variety of that contributed to the crew’s failure to Remember, visual illusions can com- different-sized runways. properly perform the approach. pletely trick you into believing every- thing looks fine — that’s why they’re Black-Hole Illusion Reducing the Risks called illusions. By far the most deadly threat while If “risk equals probability of an acci- flying an approach at night — espe- dent times its consequences,” then the 2. Do Your Homework cially during dark-night conditions — is risk is most certainly greater after dark. Determine minimum safe obstruc-

18 • www.nafinet.org tion clearance altitudes for your route of flight. Find the minimum elevation figure (MEF) on VFR sectional charts for the quadrants you will be flying over and add at least 1,000 feet (2,000 feet in mountainous) to that value since it only provides 100 to 300 feet of obstruction clearance. If you don’t have an instrument rating, learn how to determine how to fly at or above minimum en route altitudes (MEAs) as shown on IFR charts. Find out before- hand if a given airport is conducive to landing illusions. Consult the Airport/ 4. Supplement Outside References types of visual approach slope indica- Facility Directory or other publications, With Inside Ones tor systems (VASI) and use them while NOTAMs, and even other pilots to as- Flying at night is in many ways like on the approach. While many of the certain the presence of irregular-shaped instrument flying; therefore, don’t rely indications are visible up to 20 miles or runways, sloped runways, or runways solely on outside visual references to more at night, according to the AIM the conducive to black-hole conditions. accurately orient yourself. John F. Ken- visual glide path generally provides safe nedy Jr. piloted his Piper Saratoga on obstruction clearance only up to plus 3. Take Extra Precautions a 30-mile direct route over open water or minus 10 degrees of the extended Reduce your risk by avoiding VFR in VMC at night when he succumbed runway centerline out to 4 NM from flight on dark nights: Fly in what to spatial disorientation, lost control of the runway threshold. The NTSB de- the AIM calls “high lighting condi- his aircraft and crashed into the water termined that the precision approach tions,” which consist of cloud coverage seven miles off the coast of Martha’s path indicator (PAPI) at Tallahassee was less than broken (5/8th), at least 50 Vineyard. Even though he had received fully functional when the FedEx crew percent moon illumination, and flight training toward an instrument rating, allowed their B-727 to strike the trees over surface lighting that provides for it appears from the accident report short of the runway; unfortunately, adequate illumination of obstacles, ter- that he failed to adequately supple- the crew failed to effectively use the rain features and a horizontal reference ment outside visual references with system. When conducting an approach by which you can control the aircraft. his cockpit instrumentation. Haze was in Class D airspace to a runway served Use the airport taxi diagram to avoid present that evening, but even in clear by a VASI, regulations (91.129) require getting lost on the apron at night, and VMC there are times when you need to that you fly at or above the glide path request “progressive taxi instructions” use cockpit aids to vision. For example, until a lower altitude is necessary for if you’re having trouble finding your when departing into black-hole condi- a safe landing. Why not make that way around an unfamiliar airport. Raise tions use your flight instruments to your practice at every VASI-equipped your personal VFR weather minimums ensure an adequate climb gradient until runway? considerably when flying in the dark you can accurately orient yourself using As a flight instructor, you play a and resolve to stick with them if the outside visual references. If you have crucial role in educating your students weather falls below them. Pay particular glide path information from an ILS or about the hazards that lie hidden in the attention to visibility and cloud reports GPS, why not use it right down to the dark. However, you must first educate and forecasts, and accept the fact that threshold crossing height (TCH) when yourself about the unique nature of you can’t count on your vision to avoid conducting an approach at night? With these threats — and more importantly, inadvertent entry into IMC. If at all DME information from the airport you how you can effectively manage them possible, don’t let you first flight into can maintain an approximate 3 degree — before you can successfully impart an unfamiliar airport be at night, and glide slope by maintaining 300 feet this knowledge to your students. consider overflying an airport before AGL per nautical mile (NM) from the committing to an approach — especial- runway threshold. For added safety at Dale Wilson (M.S., ATP, CFI, MFI) has ly if there is high terrain nearby or you night a 500 feet per NM descent will provided flight and academic instruction suspect the possibility of an illusion. yield a 5 degree slope for better obstacle to pilots in both Canada and the United Avoid long straight-in approaches — clearance. States on human factors and flight safety they almost always result in a prema- in the aviation department at Central ture descent and low approach, even in by5. Brice Use the VASI Dommes Washington University in Ellensburg, the daytime! Make sure you know the on-glide- Washington. path indications from the various

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