Winter Cometh - Keeping Warm On A
Cold Winter Day
Reprinted with permission from FAA
As I noted in the Editor's Runway on
the inside back cover of this issue, editorially, summer is gone and winter
cometh. What this means for many pilots and aircraft owners in the Snow Belt is
a long, dark, cold period before spring flying starts again. In some cases, this
is because of the type of aircraft involved. In other cases, it is because of
the general inconvenience of flying in the cold and snow. Snow and frost removal
takes all the fun out of pre-flighting an aircraft on a cold January day. Now if
you live in Florida, Arizona, or Hawaii, you may not understand what it is like
to preflight in the cold, but please read on.
spoke with a pilot of a weight-shift trike aircraft at the Sun'n Fun Flyin last
April in Florida. Although it was T- shirt and shorts weather on the g round at
the time, he told of flying down the coast of Florida at about 3,000 feet while
wearing an insulated snowmobile outfit. He said he was comfortable at altitude,
but he was sweating because of the heat when he had to land to refuel.
those intrepid aviators who fly open or open cockpit type aircraft such as this
trike pilot or some of the ultra light or light sport aircraft during the
winter, they have to not only ensure their aircraft are prepared for the cold,
but they themselves must also be prepared. Without proper clothing and facial
protection, they risk not only hypothermia, but also frostbite on any exposed
the case of enclosed cockpit aircraft with airborne heating systems, their
pilots may be more comfortable in flight, but they face another type of danger
unique to aircraft with certain types of heaters. That is the risk that their
heaters may be leaking carbon monoxide (CO) gas into the cockpit. Carbon
monoxide is a deadly gas because it effectively prevents the blood from
absorbing oxygen vital to life. As noted in the FAA's Pilot's Handbook of
Aeronautical Knowledge, FAA - H -8083-25, on page 15-2, under the general
chapter title, Environmental and Health Factors Affecting Pilot Performance, the
handbook describes the various types of hypoxia that pilots need to be aware of.
Under the subheading of Hypemic Hypoxia, it states one of the types of hypemic
hypoxia is when, '...hemoglobin, the actual blood molecule that transports
oxygen, is chemically unable to bind oxygen molecules. The most common form of
hypemic hypoxia is carbon monoxide poisoning.'
many general aviation aircraft use part of the exhaust system to heat the air
going into the cockpit, aircraft owners and pilots need to be aware of the fact
that a hole or crack in the portion of the exhaust system that the heater shroud
surrounds can allow exhaust gas to enter the cockpit along with the heated air.
This type of heater is the most common type of heating systems installed in many
general aviation aircraft. The other type of heating system used in other
general aviation aircraft is basically a small, fuel-fed 'furnace' that heats
ram air that is directed into the cockpit. A defective or worn furnace can allow
combustion products, which includes CO, to enter the cockpit. In either system,
the best defense is a properly inspected and functioning heating system.
THE DANGERS OF CARBON MONOXIDE
reduce the risk of CO entering the cockpit along with heated air, some pilots
buy one or more of the various types of chemical and electronic CO detectors
that can be installed in an aircraft to detect dangerous levels of CO. Pilots
should review the latest handbooks and manufacturers' guidance for more detailed
information on how to recognize and cope with a heating system that is
permitting CO to enter the heating system. At a minimum, pilots should, if
suspecting a CO leaks in their aircraft, close or shut off the heating system
and open any fresh air vent or vents as applicable.
According to the Pilot's Handbook of Aeronautical Knowledge, some of the
first symptoms of hypoxia include euphoria and a carefree feeling. With more
oxygen starvation, it says '...the extremities become less responsive and flying
becomes less coordinated.' Other signs may include cyanosis (blue fingernails
and lips), headache, decreased reaction time, impaired judgment, visual
impairment, drowsiness, and lightheaded or dizzy sensation, tingling in fingers
or toes, and numbness. The handbook noted that although symptoms vary by
individual, these symptoms are common. A hidden danger in all of these is the
fact that when a pilot needs to be the most aware that a problem is developing,
the root cause of the problem may impair the pilot's judgment to the point the
pilot may not want or be able to take effective action to correct the problem.
Corrective actions for hypoxia include using supplemental oxygen, flying at a
lower altitude, shutting off the source of CO, and breathing fresh air when
PREPARING THE AIRCRAFT
Checking the aircraft's heater system is only one of the checks aircraft owners
and pilots should be aware of when preparing an aircraft for winter operations.
As I said in the Editor's Runway, the aircraft's flight and maintenance manuals
are the best sources of information for preparing your aircraft for winter
operations. The same is true of your aircraft 's maintenance personnel. They
know their local area's weather conditions and how to service your aircraft.
PREPARING THE PILOT
real challenge for safe winter flight may be preparing the pilot. In addition to
preparing their aircraft and heating system for winter operations, pilots need
to review material for their own benefit.
example, now would be a good time to review your own decision-making criteria.
What are your decision-making limitations for winter flights? If your aircraft
is not approved for flight into known icing conditions, have you considered
under what weather forecast conditions will you launch? What are your divert
you reviewed the FAA's regulations applicable for your proposed flight? Have you
reviewed the current Notices to Airmen (NOTAM) for any re ports for your
airport of departure and landing? Flying to an airport closed for snow removal
can make for a long day.
you have the appropriate survival equipment for your route of flight? FAA
Aviation News continues to support the well-publicized viewpoint that you
should wear what you want to walk home in when going flying during the winter. A
year or so ago, there was a well-publicized report of a winter accident out west
in the mountains where one of the survivors was wearing shorts. After all, no
one planned to walk home in the snow when the flight departed. Certain areas of
Canada and the State of Alaska have regulatory requirements for specific types
and amounts of survival equipment.
you considered the best use of inhabited areas and routes along highways and
other populated are as to be near help in case of an accident or precautionary
landing off airport? In many cases, a safer route may only add a few extra miles
to your flight plan while increasing your odds of rescue significantly.
you have a plan to deice or defrost your aircraft in case it gets snow covered
or exposed to freezing rain? From fuel tanks to control surfaces to landing
gear, have you considered how you would deice your aircraft? If you have a
retractable gear aircraft, does your flight manual re commend you leave the gear
down a little longer after takeoff to help blow off any potential source of
freezing liquid before retracting the gear. There have been cases where wheels
have frozen in the 'up' position. Do you have a plan for dealing with slush and
freezing rain and snow on your landing gear as you taxi out for takeoff and
after landing? What about frost on your wings?
was the last time you checked your pitot's heating system? What is your plan for
starting your aircraft if your battery dies? Do you know how to protect your
aircraft's battery when the temperature is below freezing? Do you know how to
jumpstart your aircraft? Does it have any special safety precautions for
jumpstarting? Considering the risks of hand propping an aircraft with snow or
ice on the ground, do you have a plan and a safe method for hand propping your
aircraft if you decide to do so?
you have a plan for operating on a slippery runway and ramp area? With all of
the news stories about the dangers of super-cooled water droplets, have you
considered or know how your aircraft might perform with a significant amount of
ice attached to it?
you know the capabilities of the various types of deicing and anti-icing fluids
available? Are they approved for your particular type aircraft? Some fluids have
a minimum rotation speed necessary so that the fluid will blow off the aircraft.
Is your aircraft 's rotation speed fast enough for the available fluid?
are only a few of the things a well-prepared aviator or aircraft owner needs
to think about when operating in snow country. FAA has published many snow and
winter operations advisory circulars as well as other safety recommendations for
those operating in snow country. Those living full-time in the Snow Belt should
be aware of how to operate safely when the landscape turns white and cold, but
everyday new pilots are certificated and new and old pilots from the sun-belt
venture into the frozen north. They may not know or remember the safe operating
techniques needed to flying in the cold areas and especially during the limited
daylight hours we all have during the winter months. For those pilots, we
recommend they contact the Flight Standards District Office (FSDO) Safety
Program Manager (SPM) in the area they are planning to visit for the latest
safety information. The SPM may refer you to one of the office's volunteer
aviation safety counselors who may be an expert on winter operations in that
area for more advice.
Winter can be a beautiful and safe
season for flying as long as you and your aircraft are properly prepared for its
unique challenges. The secret is simple. It is the same for any season. With
proper planning, preparation, and good risk management, you can have a safe and
fun filled winter season. But the single most important safety practice any
pilot can do is to file and activate, as appropriate, a flight plan. FAA
Aviation News hopes everyone has a safe winter-flight season.