Aircraft
And Black Holes Don't Mix
by H.
Dean Chamberlain
Reprinted with permission from FAA Aviation News
Recently, I read an article in the newest publication from the Flight Safety
Foundation called Aviation-Safety World. The article, titled 'Night VMC,'
written by Dan Gurney, says it is the 'First in a series focusing on
approach-and-landing incidents that might have resulted in controlled flight
into terrain but for the timely warnings by TAWS.' The article was about a wide
body aircraft's flight crew that misread the published approach procedure while
doing a night visual approach. Descending below the published glide path, the
aircraft might have been a controlled flight into terrain (CFIT) accident, if
the crew had not been alerted by the onboard terrain awareness and warning
system (TAWS). The article reminded me that it has been several years since we
wrote about this subject from a general aviation perspective. We want to thank
Aviation Safety World for reminding us of the need for such an article.
As we
transition from summer flying into fall and winter, one of the important
considerations that general aviation pilots have to adjust to is the reduced
number of daylight hours. Or to say it a different way, we all have to adjust to
the increasing number of 'dark hours' or the increasing number of hours of night
flying late fall and winter poses.
Although an aircraft doesn't know if it is being operated in daylight or
darkness, the impact on a pilot flying at night can be critical (no pun
intended). Since this article is only focusing on the risks of night flight, we
will leave the risks of pre-flight and flying during winter operations to
another article that focuses on winter flying and the risks posed by ice and
snow.
Although an aircraft may perform better at night due to lower density
altitude'for example, than during the midday heat'for the majority of general
aviation aircraft, the greatest impact of night flight rests on the pilot flying
the aircraft. Simply stated; at night, pilots lose many of the benefits that
daylight vision provides. In the case of the wide body aircraft in the article
mentioned, it was flying a night visual approach ''to a major airport in a
geographically remote area.' I think it is safe to say, had the crew been flying
the approach during daylight conditions, they would have noticed their descent
immediately. However, they had the onboard equipment to remind them of the low
descent. Other crews have not been so lucky. There was a Canadian military
flight involving a night visual approach accident that was later made into a
movie. In the case of the Canadian accident, the 'black hole' CFIT accident
highlighted a potential problem faced by many pilots. The Canadian flight, if I
remember correctly, cancelled its instrument flight plan within range of the
airfield and continued its flight visually. The problem was the 'black hole'
between the flight and the airfield. In the case of the Canadian flight, the
black hole was the high ground that the plane hit.
As one
of my aero club friends, who was also a flight instructor, once said on a night
flight from California back over the mountains and desert towards Arizona,
'There is a reason there are no lights out there.' He made the statement while
we were flying over the mountains east of San Diego en route to Yuma, Arizona.
As he pointed out, in many cases, the lack of lights is because people can't
build there. This usually means a steep hill, mountain, or water is at the
center of the black hole. Of course, depending upon where you are, there just
may be a lack of people in the more remote or open areas of this country, but
there is only one way for pilots to be sure. Before flying at night over an area
you are not familiar with, do your homework.
All of
this pre-supposes you are mentally and physically able and ready to fly. In a
March 2003 FAA report titled 'A Human Error Analysis of General Aviation
Controlled Flight Into Terrain Accidents Occurring Between 1990 and 1998' (by
Scott A. Shappell, Civil Aerospace Medical Institute, FAA, and Douglas A.
Wiegmann, University of Illinois at Urbana-Champaign Institute of Aviation), the
authors discussed factors relating to CFIT accidents including the pilots'
mental and physical conditions. I think, based upon some of the statements made
in this report, it is safe to say that, if you have had a long workday, you are
stressed out, you are tired, and you plan a long night flight from Point A to
Point B, you have a greater risk of having a night CFIT accident. I think this
is especially true if you are flying into a strange airport. The report noted
the importance of pilots having the required flight skills and being able to
make good, sound decisions. I think this can all be summed up by the clich'
about good decision making can prevent you from having to use your excellent
flight skills to recover from a problem of your own making.
So how
do you reduce the risk of a night CFIT accident or incident? If you are an
instrument-rated pilot flying on an instrument flight plan, don't cancel your
flight plan until you are safely on the ground. Even if you are filing an
instrument flight plan, do you carry an FAA sectional chart for the area you
will be flying over? The sectional chart shows you terrain flight risks better
than an instrument chart. In case you are wondering what I mean, if you are
flight planning an instrument route, the instrument charts specify the minimum
en route altitudes along your route. However, there may be more than one route
to your location. One may be over rough terrain, water, or even mountains that
might make an off-airport landing risky. But the alternate route might be over
more friendly terrain and might even have an airport or two within easy gliding
distance along the route. The route choice is yours whether you are flying on an
instrument flight plan or a visual flight plan. If you are flying a high
performance multiengine aircraft with a drift down altitude that is higher than
the en route terrain, no problem. If you are flying a multiengine airplane with
a drift down altitude that is below the rough terrain peaks, or if you are
flying a single engine aircraft with a zero drift down altitude, then you might
want to consider the more friendly route at night when the risk of an
off-airport landing increases. This is just one consideration when flight
planning at night.
Another consideration is operations in the terminal area. Since every student
pilot has to study many of the visual limitations of the human eye during ground
school, we will not republish the Aeronautical Information Manual (AIM) and the
FAA's Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25) sections about
aero medical issues involving night vision, spatial disorientation, and
illusions that can occur during night flight. However, we do want to highlight a
section from the handbook. On page 15-5 in the Pilots Handbook, it states,
'Various surface features and atmospheric conditions encountered in landing can
create illusions of being on the wrong approach path. Landing errors from these
illusions can be prevented by anticipating them during approaches, inspecting
unfamiliar airports before landing, using electronic glide slope or VASI systems
when available, and maintaining proficiency in landing procedures.'
The
handbook continues by saying, 'A narrower-than-usual runway can create the
illusion that the airplane is higher than it actually is, while a
wider-than-usual runway can have the opposite effect, causing the pilot to flare
too high or overshoot the runway.'
'A
runway that slopes up, or up-sloping terrain, can create the illusion that the
airplane is at higher altitude than it actually is and down sloping runways or
terrain can create the opposite effect. Rain on the windshield can create the
illusion of greater height, and haze can make distances appear greater than they
are.'
These
visual effects are real. So what can anyone do to reduce the risk of a general
aviation night CFIT accident or incident? First, if you have access to the
Internet, you can search the Internet for additional information. In my search,
I found both non-government and government articles and information about night
flight. Of particular interest was the amount of FAA material involving
helicopter emergency medical services (HEMS) operations. As a January 2006 FAA
Safety Alert for Operators (SAFO) stated, 'HEMS operate in a demanding
environment.' The SAFO noted the number of commercial HEMS accidents from
January 1998 through December 2004 that involved CFIT, night operations, and
inadvertent flight into instrument meteorological conditions (IMC). Of the
21fatal HEMS accidents noted, the SAFO said 21 occurred during night operations.
I am
not implying that the average general aviation pilot faces the unique risks the
HEMS crews face when landing on a highway somewhere to pick up an accident
victim. But the various FAA HEMS reports do point out some ideas that GA pilots
can use to reduce their night flight risks.
Some
of those ideas include good decision-making. The first decision every pilot must
make when planning a night flight is should the flight be made. When applying
good risk analysis, the right decision may be to delay the flight until the next
day.
Another factor is, how proficient are you flying at night? This involves the
perennial question of legal currency versus proficiency. You may be legal, but
are you safe. Please note, to ensure night currency involving being pilot in
command (PIC) while carrying passengers, your required landings must be to a
complete stop in the same aircraft category, class, and type, if a type rating
is required. For a complete list of night currency requirements to be PIC
carrying passengers at night, you should review Title 14 Code of Federal
Regulations (14 CFR) section 61.57(b). If you are not comfortable flying at
night, you should arrange for some night instruction with a qualified and night
current flight instructor.
The
SAFO also pointed out the need for ground and flight training in aircraft system
malfunctions and the importance of good aeronautical decision-making including
the decision to divert, continue, or terminate the flight.
For
those aircraft so equipped, the SAFO pointed out the benefit of using a radar
altimeter if available, the use of enhanced vision systems, and the use of a
Terrain Awareness Warning System. These are all tools to increase safety, which
reduces your flight risk. Some of the new GPS-based terrain awareness tools
being developed offer a lot of promise.
The
SAFO emphasized the benefit of a good weather brief and the possibility of
raising your own minimum weather minimums to increase your safety. The need for
a complete weather brief and updating that information in flight was also
highlighted.
As
noted earlier, the need to review significant terrain and obstacles along your
route of flight starting from your departure airport to your destination and any
required alternate airports cannot be emphasized enough.
One
item I don't remember ever seeing before was a recommendation to, 'Make pilot
compartment, to the extent possible, free of glare and reflections. Ambient
light may have been a factor in some of the night accidents.' Although the
report was referring to helicopter operations, I think this recommendation makes
a good point.
Pilots
should also reduce personal distractions when taking off and landing. The
airline sterile cockpit concept of only operational conversations during
takeoff, and below 10,000 feet for some, is one way to reduce potential
distractions.
I
found another important recommendation searching the Internet. It was in an
article written by Ken Steiner posted on the San Carlos Airport Pilots
Association Aviation Safety Page. In the article Steiner (the article said he
was the Claims Manager and Assistant Vice President for the San Francisco office
of the United States Aircraft Insurance Group and active in accident
investigation) told of one accident that ''took place on a crystal clear,
moonless night at a remote desert airport. Although visibility was otherwise
excellent, witnesses described conditions as pitch black with no visible
horizon. The 2,000-hour, instrument pilot took off from a lighted runway. Within
half-a-mile of the runway departure end, the aircraft went into a 90 degree left
bank. The left wing tip struck the ground causing the aircraft to cartwheel
resulting in the destruction of the aircraft and two fatalities.' Steiner said
this was a classic black hole accident where, on a dark night visual references
are limited or non-existent, a pilot must be able to transition from VFR
conditions to instrument conditions in, as he said, a blink of an eye.
This
accident illustrates the fact that night flight operations can be deadly
immediately upon takeoff for the unprepared. Add in the risks en route, such as
inadvertent flight into clouds or IMC and the possibilities of fog or other
obstructions to vision at the landing airport, and you can begin to see that
night flight requires extra preparation and planning. In one case involving a
turbojet departing from the San Diego area several years ago, the pilot decided
to pick up his instrument flight plan after takeoff. Departing visually at
night, the aircraft hit a mountaintop east of San Diego killing all onboard. The
pilot failed to see and avoid the mountaintop hidden in the 'black hole' east of
the city.
The
risks are real. Preparation is the key to a successful flight. Another technique
that can reduce night landing accidents is to know the published altitude of the
field. Rather than depend upon your eyes alone in flying your approach, you
should base your approach altitude upon that of the airfield. This is one way to
minimize the visual affects of wide, narrow, or sloping runways. Another
technique is to use all available approach lights, such as VASI and other runway
lights. If the airport has pilot controlled lighting, be aware that the lights
may switch off if you activated them early in your arrival process. You might
want to key the activation code again on base to final or on final approach. The
FAA Airport/Facility Directory (AFD) for the airport will tell you how to key
the pilot controlled lighting. The AFD will also list what other flight aids
will be available. For example, the Laurier, Washington, listing for Avey Field
includes a remark that 'Rwy marked with retro reflective devices.' Examples for
other airports include recommended night landing runways, types of warning
lights, and the lack of lights. An important risk to consider at smaller
airports is unlit towers. Notices to Airmen (NOTAM) may report those lighted
towers near airports that are out of service. The best defense against all
towers is to check your charts for any listed towers and to maintain your en
route altitude as long as possible.
A
final recommendation is to use all available navigation aids and information.
Any type of glide path guide, whether electronic or visual, will keep you out of
the trees at the end of the runway. If you have access to the latest approach
procedure for the airport, the published data will provide altitude information
throughout the approach. A through review of the AFD for the airport will also
provide important information. A final check for any NOTAMs is important. You
don't want to arrive at the airport expecting to use runway lighting, if the
lights are out of service.
These are only a few safety
recommendations for night operations. The key to having a safe flight is
adequate preparation and a qualified, current, and rested pilot able to make
good decisions. Have a safe season of night flying. Remember to file a flight
plan if going VFR, and be careful when flying near black holes; you don't know
what might be lurking there. What you don't know can kill you.
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