Introduction
Winter flying can be some of the most enjoyable flying you will ever do. It can also be
some of the most dangerous. Weather conditions with, strong and gusty winds, blowing
drifting snow, and icing conditions are just part of the conditions that require careful
planning in order to minimize their effect on your enjoyment of flying your ultralight.
TIPS ON WINTER FLYING
Most accidents occur around the home - and most winter ultralight accidents occur
within a 50 miles radius of your home base. Thus it is important that you
file a flight plan, or flight itinerary, with someone for every flight, and a that
you brush up on your knowledge on winter survival techniques. Experience has shown that
the advice of operators who are located in the area where the flight is to occur is
invaluable, fish hut operators for example are an excellent source of information on ice
and weather conditions. Take advantage of their years of experience on the lake or lakes
that you are looking to fly over. It only takes a phone call and they are listed in all
the telephone books. Local weather channels are also a good source of information, as are
local radio and television stations.
If you are flying to a friends place, always give yourself an out by informing him or
her that you intend to fly and will arrive at a certain time, unless the weather
conditions are unfavorable. Remember it is your responsibility to familiarize yourself
with all the information necessary for a safe flight. The final decision to go, not to go,
or to turn back rests with you and you alone. Don't push yourself into making a decision
that could result in an accident. There are many more days that you CAN
fly as long as you and your plane are still in one piece.
PREPARATION
If you have only flown your craft during the warmer summer months, you may not
realize that things are quite different in the winter.
There are three things that you have to prepare:
The Plane
The Engine
The Pilot
The Plane:
I have flown ultralights for
nearly 30 years and have yet to see an ultralight manufacturers checklist for winter operation. So using the experience accumulated over
this time here are some of the things that you might do during the winter months, to help
ensure safe, fun ultralight flying.
Tips On Winter Flying in your ultralight!
Introduction
Winter flying can be some of the most enjoyable flying you will ever do. It can also be
some of the most dangerous. Weather conditions with, strong and gusty winds, blowing
drifting snow, and icing conditions are just part of the conditions that require careful
planning in order to minimize their effect on your enjoyment of flying your ultralight.
TIPS ON WINTER FLYING
Most accidents occur around the home - and most winter ultralight accidents occur
within a 50 miles radius of your home base. Thus it is important that you
file a flight plan, or flight itinerary, with someone for every flight, and a that
you brush up on your knowledge on winter survival techniques. Experience has shown that
the advice of operators who are located in the area where the flight is to occur is
invaluable, fish hut operators for example are an excellent source of information on ice
and weather conditions. Take advantage of their years of experience on the lake or lakes
that you are looking to fly over. It only takes a phone call and they are listed in all
the telephone books. Local weather channels are also a good source of information, as are
local radio and televison stations.
If you are flying to a friends place, always give yourself an out by informing him or
her that you intend to fly and will arrive at a certain time, unless the weather
conditions are unfavorable. Remember it is your responsibility to familiarize yourself
with all the information necessary for a safe flight. The final decision to go, not to go,
or to turn back rests with you and you alone. Don't push yourself into making a decision
that could result in an accident. There are many more days that you CAN
fly as long as you and your plane are still in one piece.
PREPARATION
If you have only flown your craft during the warmer summer months, you may not
realize that things are quite different in the winter.
There are three things that you have to prepare:
The Plane
The Engine
The Pilot
The Plane:
I have flown ultralights for over 20 years and have yet to see an ultralight
manufacturers checklist for winter operation. So using the experience accumulated over
this time here are some of the things that you might do during the winter months, to help
ensure safe, fun ultralight flying.
Winter covers and control system locks-If your plane is left outside exposed to
wind and snow I recommended covering exposed engines, windshields, and locking
control systems.
For more info check out and
For more info check out
Engine Oil- On four stroke engine like the 912/912S/914 oil condition and weight
is extremely important in low temperatures. Check your owner’s manual for the proper
weight of oil to be used in low temperature ranges. Also note recommended starting
procedures – you will note that at low temperatures it is recommended that the engine
be turned over by hand first and that the engine where possible be pre heated. This is
especially true if you have an older 912 – the starter ratio was higher putting more
load on the battery.
Cabin Heater Many aircraft are equipped with cabin heater shrouds, which enclose
the muffler or portions of the exhaust system. It is imperative that a thorough inspection
of the heater system be made to eliminate the possibility of carbon monoxide entering the
cockpit or cabin area. If you have this kind of heater installed make sure to install a
carbon monoxide detector unit in your plane.
My recommendation is NOT to use this kind of heating system.
Cabin heat can be supplied on most Rotax engines via the fan on air-cooled engines and by
the installation of a "liquid heater" running off the cooling system on liquid
cooled two and four stroke engines.
For more info check out
Control Cables-Because of contraction and expansion caused by temperature
changes, control cables should be properly adjusted to compensate for the temperature
changes. Another factor is what cold can do to a control system - many pilots have
reported frozen throttle cables, throttle slides, and control system cables such as
ailerons, rudder, and elevator.
Propellers-Propeller difficulties in some electric and hydraulic controlled
propellers can be encountered due to ice and congealed oil. Ice can form on the
"adjusting screw" Also wood propellers can be adversely affected by cold, snow
and ice. Do a thorough preflight looking for knicks, cracks, or splits. A small split at
the end of the prop can quickly follow the wood grain up the prop resulting in an in air
failure.
Batteries
- Batteries require special attention during cold weather. Keep them
fully charged or removed from the aircraft when parked outside to prevent loss of power
caused by cold temperatures and the possibility of freezing. Also make sure you have the
correct AMP hour rating. A battery that turns an engine over in the summer may not have
the necessary amps to do the same in winter. This can result in damage to the starter, ring gear etc.
Liquid Cooling: Remember your cooling fluid has to be checked for the
proper amount of anti -freeze. Rotax recommends a 50/50 distilled water to antifreeze
mixture for winter operation on their two stroke engines and an 80% ratio on the 912/914.
Wheel Pants-Thawing conditions, result in mud and slush which can be thrown into
wheel pants during taxiing and takeoff. If frozen during flight, this mud and slush will
lock up the wheel which could result in an accident on landing on a hard or paved
surface. It is recommended that wheel pants be removed to prevent the
possibility of frozen substances locking the wheels or brakes. With wheel pants removed be
careful that mud etc does not come off and go into the prop during a take off or landing.
OPERATION OF AIRCRAFT
The thoroughness of a preflight inspection is important in temperature extremes. It is
natural to hurry over the preflight of the aircraft and equipment, particularly when the
aircraft is outside in the cold. However, this is the time you should do your best
preflight inspection.
Fuel Contamination-Fuel contamination is always a possibility in cold climates.
Even with the best of fuel and fueling precautions, if your aircraft has been warm and
then is parked in the cold, the possibility of condensation of water in the tanks exists.
As a precaution, it is suggested:
- Where possible, buy your fuel from a busy station, fly your craft so as to leave as
little as possible fuel in the tanks, and put fresh fuel in just prior to each flight.
Always drain fuel sumps to remove any water, which may have been introduced.
- Be sure the fuel being used is, fresh, properly mixed if required and is the
correct grade (octane) for your engine.
- Be sure to filter the fuel as it goes into your tanks the best funnel on the market for
doing this is Mr. Funnel - a water separator funnel available from most ultralight supply
stations.
I have tested this funnel - IT WORKS!-DL
Aircraft Fuel Filters and Sumps- Fuel filters and sumps (including each tank
sump) should be equipped with quick drains. Sufficient fuel should be drawn off into a
transparent container to see if the fuel is free of contaminants. Experienced operators
place the aircraft in level flight position, and the fuel is allowed to settle
before sumps and filters are drained. All fuel sumps on the aircraft are drained including
individual tank sumps. Extra care should be taken during changes in temperature,
particularly when it nears the freezing level. Ice may be in the tanks which may turn to
water when the temperature rises, and may filter down into the carburetor causing engine
failure. During freeze-up in the fall, water can freeze in lines and filters causing
stoppage. If fuel does not drain freely from sumps, this would indicate a line or sump is
obstructed by sediment or ice. It is usggested you use gas line anti-freeze - the
same as used in snowmobiles to help prevent this. Where aircraft fuel tanks do
not have quick drains installed, it is advisable to drain a substantial amount (1 quart or
more) of fuel from the gascolator; then change the selector valve and allow the fuel to
drain from the other tank.
Aircraft Preheat- Low temperatures can change the viscosity of engine oil,
batteries can lose a high percentage of their effectiveness, instruments can stick, and
warning lights, when "pushed to test," can stick in the pushed position. Because
of the above, preheat of engines as well as cockpit before starting is considered
advisable in low temperatures.
Extreme caution should be used in the preheat process to avoid fire. The following
precautions are recommended:
- Preheat the aircraft by storing in a heated hangar, if possible.
- Use only heaters that are in good condition and do not fuel the heater while it is
running.
- During the heating process, do not leave the aircraft unattended. Keep a fire
extinguisher handy for the attendant.
- Do not place heat ducting so it will blow hot air directly on parts of the aircraft;
such as, upholstery, canvas engine covers, flexible fuel, oil and hydraulic lines or other
items that may cause fires.
Be sure to follow the manufacturer's procedures.
Block heater: In many cold climates cars come
equipped with block heaters as standard equipment. There are many after market units that
have hoses that are the same size as your heater hose. A trick I use is to install a
small inline block heater into the heater line. Plug it in about 10 minutes before flight
and the engine, and heater are up to temp and working when your ready to go flying.
Engine Starts-In moderately cold weather, engines are sometimes started without
preheat. Particular care is recommended during this type of start. Oil is partially
congealed and turning the engines is difficult for the starter or by hand.
This also results in poor compression and, consequently, harder starting. Sometimes
aircraft fires have been started by over prime, when the engine fires and the exhaust
system contains raw fuel. Other fires are caused by backfires through the carburetor. It
is good practice to have a fire extinguisher handy during these starts.
Radios- Should not be tuned prior to starting. Radios should be turned on after
the aircraft electrical power is stabilized, be allowed to warm-up for a few minutes and
then be tuned to the desired frequency.
Removal of Ice, Snow, and Frost- A common winter accident is trying to take off
with frost on the wing surface. It is recommended that all frost, snow, and ice be removed
before attempting flight. It is best to place the aircraft in a heated hangar. If so, make
sure the water does not run into the control surface hinges or crevices and freeze when
the aircraft is taken outside. Don't count on the snow blowing off on the takeoff
roll. There is often frost adhering to the wing surface below the snow.
Caution should be used if an aircraft is taken from a heated hangar and allowed to sit
outside for an extended length of time when it is snowing. The falling snow may melt on
contact with the aircraft surfaces and then refreeze. It may look like freshly fallen snow
but it usually will not blow away when the aircraft takes off.
Blowing Snow- If an aircraft is parked in an area of blowing snow, special
attention should be given to openings in the aircraft where snow can enter, freeze solid,
and obstruct operation. These openings should be free of snow and ice before flight. Some
of these areas are as follows:
- Pitot Tubes
- Radiators
- Carburetor intakes
- Elevator and aileron controls and cables
- Main wheel and tail wheels and wheel pants.
Fuel Vents- Fuel tank vents should be checked before each flight. A vent plugged
by ice or snow can cause engine stoppage, collapse of the tank, and possibly very
expensive damage.
Taxiing- A pilot should keep in mind that braking action on ice or snow is
generally poor. Short turns and quick stops should be avoided. Do not taxi through small
snowdrifts or snow banks along the edge of the runway. Often there is solid ice under the
snow. If you are operating on skis, avoid sharp turns, as this puts torque on the landing
gear in excess of that for which it was designed. Also for ski operation, make sure safety
cables and shock cords on the front of the skis are carefully inspected. If these cables
or shock cords should break on takeoff, the nose of the ski can fall down to a near
vertical position which seriously affects the aerodynamics efficiency of the aircraft and
creates a landing hazard. For more info check out
If it is necessary to taxi downwind with either wheels or skis and the wind is strong, get
help or don't go. Remember, when you are operating on skis, you have no brakes and no
traction in a crosswind. On a hard-packed or icy surface, the aircraft will slide sideways
in a crosswind and directional control is minimal particularly during taxiing and landing
roll when the control surfaces are ineffective.
TAKEOFF
Takeoffs in cold weather offer some distinct advantages, but they also offer some
special problems. A few points to remember are as follows:
- Care should be exercised in operating normally aspirated engines. Power output increases
at about 1 % for each ten degrees of temperature below that of standard air. At -40
degrees F an engine will develop 10% more than rated power even though RPM and MP limits
are not exceeded.
- If the temperature rises, do not expect the same performance from your aircraft as when
it was operated at the lower density altitudes of cold weather.
It is wise to anticipate the loss of an airspeed indicator or most any other instrument
during a cold weather takeoff-especially if the cabin section has not been preheated.
Climb out- During climb out, keep a close watch on EGT/water temp/head
temperature gauges. Due to restrictions (baffles) to cooling airflow installed for cold
weather operation and the possibility of extreme temperature inversions, it is possible to
overheat the engine at normal climb speeds. If the temperatures nears the critical stage,
land immediately find out why and do not commence flight until the problem has been
eliminated.
EN ROUTE
Weather- Weather conditions vary considerably in cold climates. Winter weather
is often very changeable; one minute it may be great flying weather and five or ten
minutes later VFR may not be possible. Remember, winter flying and bad weather don't mix.
Set yourself some limits and stick to them.
Snow showers and Whiteouts- Snow showers are, of course, quite
prevalent in colder climates. When penetration is made of a snow shower, the pilot may
suddenly find himself without visibility and in IFR conditions. Snow showers will often
start with light snow and build. Another hazard, which has claimed as its victims some
very competent pilots, is the "whiteout." This condition is one where within the
pilot's visibility range there are no contrasting ground features. Obviously the smaller
the visibility range the more chance there is of a whiteout; however, whiteout can occur
in good visibility conditions.
The following is included for information purposes - on two stroke engines
conventional style of carb heat is not recommended. A two stroke engine is not as prone to
carb icing as a four stroke. There are several reasons for this.
First - the airflow into a two stroke is not constant - it pulses back
and forth.
Second - the carb is rubber mounted to the engine manifold which helps
stop the transfer of heat/cold.
Third - the gas contains oil which also helps prevent freezing.
Fourth - you should be using Premium Fuel which has additives to prevent
carb icing.
This is not to say carb icing can not happen - it has happened to me once in nearly
16,000 hours of flying. But adding heat to air entering the engine is not good for a two
stroke engine. An alternative is to use electric carb heaters which heat the carb body.
These are available from LEAF/CPS/Aircraft Spruce.
Carburetor Ice-Three categories of carburetor ice are:
- Impact ice formed by impact of moist air at temperatures between 15-32 degrees F on
airscoops, throttle plates, heat valves, etc. Usually forms when visible moisture such as
rain, snow, sleet, or clouds are present. Most rapid accumulation can be anticipated at 25
degrees F.
- Fuel ice forms at and downstream from the point that fuel is introduced when the
moisture content of the air freezes as a result of the cooling caused by vaporization. It
generally occurs between 40 and 80 degrees F but may occur at even higher temperatures. It
can occur whenever the relative humidity is more than 50%.
- Throttle ice is formed at or near a partly closed throttle valve. The water vapor in the
induction air condenses and freezes due to the venturi effect cooling as the air passes
the. throttle valve. Since the temperature drop is usually around 5 degrees F, the best
temperatures for forming throttle ice would be 32 degrees to 37 degrees F although a
combination of fuel and throttle ice could occur at higher ambient temperatures.
In general, carburetor ice will form in temperatures between 32 degrees and S0 degrees
F when the relative humidity is 50% or more. If visible moisture is present, it will form
at temperatures between 15 and 32 degrees F. A carburetor air temperature gauge is
extremely helpful to keep the temperatures within the carburetor in the proper range.
Partial carburetor heat is not recommended if a C.A.T. gauge is not installed. Partial
throttle (cruise or letdown) is the most critical time for carburetor ice. It is
recommended that carburetor heat be applied before reducing power and that partial power
be used during letdown to prevent icing and overcooling the engine.
To prevent:
- use carb heat ground check
- use heat in the icing range
- use heat on approach and descent
If it occurs-Warning signs:
loss of rpm (fixed pitch)
drop in manifold pressure (constant speed) rough running
Pilot response:
apply full carb heat immediately
(may run rough initially for short time while ice melts)
The curves encompass conditions known to be favorable for carburetor icing. The
severity of this problem varies with different types, but these curves are a guide for the
typical light aircraft.
Caution-light icing over a prolonged period may become serious.
When you receive a weather briefing, note the temperature and dewpoint and consult this
chart.
Serious Icing - cruise or climb power
Moderate Icing - Cruise power or serious icing -
glide power
Serious Icing - glide power
Light Icing - glide or cruise power
Carbon Monoxide Poisoning- Don't
count on symptoms of carbon monoxide to warn you: It's colorless, odorless, and taste-less
although it is usually found with exhaust gases and fumes. If you smell fumes or feel any
of the following symptoms, you should assume that carbon monoxide is present.
Feeling of sluggishness, warmth, and tightness across forehead followed by headache,
throbbing, pressure at the temples and ringing in the ears. Severe headache, nausea,
dizziness, and dimming of vision may follow. If any of the above conditions exist, take
the following precautions:
- Shut off the cabin heater or any other opening to the engine compartment.
- Open a fresh air source immediately.
- Don't smoke.
- Use 100% oxygen if available.
- Land as soon as possible.
- Be sure the source of the contamination is corrected before further flight.
Spatial disorientation can also be expected any time the pilot continues VFR flight
into adverse weather conditions. Flying low over an open body of water during low
visibility and a ragged ceiling is another ideal situation for disorientation.
Blowing Snow and Ice Fog- Blowing snow can be a hazard on landing, and a close
check should be maintained throughout the flight as to the weather at destination. If the
weather pattern indicates rising winds, then blowing snow may be expected which may
necessitate an alternate course of action.
Ice fog is a condition opposite to blowing snow and can be expected in calm conditions
about -30 degrees F and below. It is found close to populated areas, since a necessary
element in its formation is hydrocarbon nuclei such as found in automobile exhaust gas or
the gas from smoke stacks.
Both of the above conditions can form very rapidly and are only a few feet thick
(usually no more than 50 feet) and may be associated with clear en route weather. A
careful check of the forecast, weather, and cautious preflight planning for alternate
courses of action should always be accomplished.
LANDING
A landing surface can be very treacherous in cold weather operations. In addition,
caution is advised regarding other hazards such as snow banks on the sides of the runways
and poorly marked runways. Advance information about the current conditions of the runway
surface should be obtained. If it is not readily available, take the time to circle the
field before landing to look for drifts or other obstacles. Be aware that tracks in the
snow on a runway do not ensure safe landing conditions. Often snowmobiles will use runway
areas and give a pilot the illusion that aircraft have used the airport and the snow is
not deep.
Ski Wheels- Ski wheel combinations are popular and very convenient; however,
forgetting to use the landing gear appropriate to the runway surface can be embarrassing.
Skis-In-level flight, skis due to their relatively dirty profile will cut cruising
speed to some extent. In addition to some loss of aerodynamic efficiency, skis have other
disadvantages. They require more care in operating because bare spots must be avoided to
keep from wearing the bottom coating of the skis, although the bottom coating must be
renewed on some skis periodically. There is now on the market an anti-friction tape which
is very useful for this purpose. Skis equipped with the antifriction coating do not freeze
to the surface like those which expose bare metal to the snow. Another method of keeping
skis from freezing to the snow is to taxi the aircraft up onto poles placed across and
under the skis. This prevents them from touching the snow for most of their length.
Extra care in use of skis during takeoff and landing is also recommended. Rutted snow
and ice can cause loss of ground control, even failure of skis or landing gear parts. Deep
powder snow can adversely affect ski operation. Prolonged takeoff runs in deep powder are
expected and it may be deep enough that no takeoff is possible under existing conditions.
In this case, experienced operators pack a takeoff path with snowshoes or taxi back and
forth until an adequately packed runway is available.
POST FLIGHT
The following are a few items to consider before leaving the aircraft after the flight:
- If the aircraft is to be left outside, put on engine covers and pitot covers.
- If the weather forecast is for snow or "clear and colder," wing covers
and save yourself from a snow or frost removal job in the morning.
- Control locks are suggested if the aircraft is left outside, and there is a chance
of high wind conditions. Tie downs are, of course, also suggested in high winds.
SURVIVAL
After a crash landing, it is best to leave the aircraft as soon as possible. Take time
to analyze the situation and help others. Take care of any injuries first. Stay away from
the aircraft until all gasoline fumes are gone. Sit down and think. Keep in mind
that survival is 80% mental, 10% equipment, and 10% skills. Since mental factors are the
number one problem, establish a goal to conquer regardless of the consequences. Don't have
"give-up-itis" or a "do-nothing-attitude." Don't run off without
taking time to think out each problem. Don't imagine things that are not there. There are
basic fears in each of us. They are:
- Fear of the unknown
- Fear of darkness
- Fear of discomfort
- Fear of being a-lone
- Fear of animals
- Fear of death
- Fear of punishment
- Fear of personal guilt
Your is the best tool for survival. Use it.
The number one enemy is yourself.
The number two enemy is injuries.
The number three enemy is temperature.
The number four enemy is disease.
Whether to stay with the aircraft or start out on foot may be a major decision. Did you
file a flight plan /flight itinerary? If you did, it may be best to let them find you.
Do you have a survival kit? Don't fight a storm. Stay put and find shelter. Most
storms are of short duration. What do you have in the aircraft that can be used to aid in
survival?
- The compass will keep you going in one direction.
- Gasoline will help make a fire.
- Oil can be used for smoke signals.
- Seat upholstery may be used to wrap around feet or hands.
- Wiring may be used for tie strings.
- The battery may be used to ignite fuel.
Use whatever is available to protect the body from the loss of heat. Don't waste body
heat by eating snow. Make a fire; heat water before drinking. You can conserve energy to
last three weeks if you have water and stay dry. Body heat can escape 240 times faster
from wet clothing than from dry clothing. It is best to eat small amounts of sugary foods
to rep-lace the energy lost through body heat. A good survival kit is well worth its
weight. The following would be a useful kit; however, you can assemble an inexpensive
survival kit of your own.
- First you need a metal container with a lid. This container can be used to heat water,
make tea, use as a digging tool or polished as a signal mirror.
- Boy Scout knife.
- Small candle.
- Penny box of matches (wrapped in plastic).
- Leaf bag (pull over head, cut hole for face).
- Garbage bag (step in, pull up and tuck in pants or tie around waist). You now have body
protection from heat loss.
- Sugar cubes (wrap in plastic, 6 to 12 cubes).
- Plastic tape.
The above is only a sample of what can be done. Use your own innovation and remember
survival depends upon you.
PRIVATE AIRCRAFT-DOWNED AIRCRAFT-LIFE SUPPORT KIT
(Components of this vital kit may be found in most homes and garages.)
Container: Any Lightweight metal container with lid, suitable to heat and store water.
Life Support Tools:
- Hack saw-Single handle with wood blade and metal blade
- Pliers-vise grip
- Pliers-slip joint
- Screwdriver set (multiple)
First Aid Kit-Personal:
- Sealable Plastic Container
- 2-Compress bandages
- 1-Triangle bandage
- Small roll 2" tape
- 6- 3 x 3 gauze pads
- 25-Aspirin
- 10-Band-Aids
- Razor blades or scissors
- Hotel size soap
- Kotex-purse size
- Kleenex-purse size, or toilet paper
- 6-safety pins
- 1 -Small tube of Unguentine or Foile
Shelters (minimum of 2)
- Large plastic sheets - 9' x 12' Heavy gauge (one for each person) colored red or yellow
preferred for signal panels.
Life Support Kit
- Waterproofed matches
- Candle or fire starter
- Signal mirror
- Compass-small
- Knife - Boy Scout style
- Insect repellent
- Mosquito net
- whistle
- 50' of 1/8" nylon rope or shroud line
- Smoke flares or red day-night flares
- Food and Energy Package-1 Man 5-day rations 2 or 3 cans of Sego, Nutriment or Metrecal
for liquid and energy
- 30 -sugar cubes - wrapped
- 10 - pilot bread or 25 crackers
- 10-packets of salt
- 3 - tea bags
- 12 - rock candy
- 5-gum
- 10 bouillon cubes
- 20 - protein wafers (if available)
Use poly bags for water storage
Put each item in small plastic bag and seal. Put everything in small metal can (cook
pot), seal with poly bag and tape.
Requirements for Life:
- You can live without it approximately
- Air............................3 minutes
- Body Shelter................6 hours in severe weather
- Water.........................3-6 days
- Food..........................3 weeks
- Will to live....................?
Wind Chill - Without the wind blowing, the body (normally covered) can withstand
a greater degree of cold. But let the wind blow, even a slight breeze, and the body heat
loss can become critical. Of course, body heat is a product of energy. The chart below
will give you an idea as to what to expect in equivalent temperatures. It also points a
need for protective clothing or shelter.
To use the chart, find the estimated or actual wind speed in the left-hand column and
the actual temperature in degrees F. in the top row. The equivalent temperature is found
where these two intersect. For example, with a wind speed of 10 mph and a temperature of
-10 degrees F, the equivalent temperature is -33 degrees F. This lies within the zone of
increasing danger of frostbite, and protective measures should be taken. It is emphasized
that the wind chill chart is of value in predicting frostbite only to exposed flesh.
Outdoorsmen can easily be caught out in 30 degrees temperature. Winds of 30 mph will
produce an equivalent wind chill temperature of -2 degrees
For more information on emergency survival check out:
Emergency crash survival-Are you equipped?
Aviation crash survival kit.
-30-
U.B. Judge.
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