The Pilot's Lounge #5:
Yes, It's Winter
Brrr, it's cold out there. If recent storms in the U.S. weren't enough of a sign, be assured that winter has arrived. Should the change in season mean grounding your bird until the swallows fly home to Capistrano? Winter flying has its own set of challenges, but also brings with it many rewards as long as a pilot is properly prepared. AVweb's Rick Durden takes on the season's challenges in a detailed discussion of the many planning and operational considerations pilots should think about this time of year.
It had been a very good winter day. About a dozen of us stuck around here in the pilot's lounge after the sun went down, even though snow was falling and a blizzard was forecast. We were getting warm after dealing with the challenges of working with little airplanes in cold weather and talking about our days and, of course, the cold. Some of the pilots had gone for the hundred-dollar hamburger, instructors had been flying with students and a few had returned from trips. Two of the charter pilots were filling out the paperwork after freight runs. This evening, the conversation concentrated on cold-weather flying. Some of the students perked up: One had had difficulties with frozen brakes and another had not been able to start a Warrior.
I sat and listened, as I've found that I usually learn quite a bit on these evenings. I'm hoping I was able to get the gist of what was discussed, as there was a quite a bit of stuff.
Our airport is far enough north that we have a serious winter, so we talked about cold-weather operations for those folks who have to fight the low temperatures and snow for a few months each year. We couldn't presume to tell the pilots in Alaska or northern Canada how to operate in the cold. From about 1927, when Bernt Balchen helped Western Canadian Airlines set up an all-weather airline service using Fokker Super Universals in the Hudson Bay area, the folks in the nort'woods have been writing the book on cold-weather flying. Those pilots will undoubtedly be able to add to what I've copied down. (I'll tell you more about Bernt Balchen, the father of cold-weather flying, next month.)
For starters, everyone agreed with one thing: In the cold, allow extra time. For everything. Accept it. Plan for it. With that in mind, everything else goes pretty well.
If you are a renter, particularly if you are the first user of the day, show up about two hours before you intend to depart. It is likely that it will take that long to get the hangar opened, to get the area in front of the hangar or tie-down cleared of snow, for the line folks to get the fuel truck started and service the airplane (Murphy's law requires that it wasn't fueled last night), to get the frost off the airplane, to get it started and to simply get to the runway. Too often, renters show up on time and work like mad to get the airplane ready to go, only to discover they have used up their two-hour slot. As we say, it was nice of them to have gotten the airplane all ready to go for the next pilot. Ever notice that smart renters never sign up for the first slot in the winter?
Planning For The Season
Before the first snow is expected, take the wheel pants off. Wheel pants collect snow and ice, which in turn can prevent the wheel from rotating freely. If you happen to slide into something hard, a bare tire will bounce off. A wheel fairing will crack or break, especially when brittle from the cold.
If you have a winterization kit, don't forget to install it once the temperature drops to the published range. (Operating above the suggested range can cause problems with high oil temperatures.)
The pilots here in the lounge who fly throughout the winter also have CO detectors on the panel as they know exhaust systems wear out. Every year, there are a few accidents due to CO poisoning. The pilots who fly all winter also have their cabin heating systems looked over in November. Several of them have their annuals come due in October so that they can get the airplane ready for the tough winter flying season.
NOTE: See Mike Busch's in-depth article on the CO safety threat and his recommendations for digital CO detectors for in-flight use.
Most of the Cessna owners said they cover up the cabin air inlet openings on the wings. Some use duct tape, while others use commercially available attachments. All said that it makes a big difference in cabin comfort. The pilots who have been around also make sure that the baggage curtain behind the back seat seals well. Most of the cold drafts come from the tail of the airplane. A bunch of the newer pilots were amazed to learn that the airflow within the airplane is from the aft fuselage towards the front, which explains why the rear seat passengers are so much colder than those in the front.
More than one pilot had a copy of Fred E. Potts' book, Guide To Bush Flying, which is one of the definitive works on, among other things, cold-weather flying. Fred is an interesting sort; after having flown the bush for years, he literally "wrote the book" about how to do it. His book is on the web at www.fepco.com.
We in the lounge have noticed that the charter pilots aggressively seek out as much weather information as they can before flying in the winter. As someone always worried about thunderstorms, I was interested in the reasons why. They pointed out that winter weather can be very complex, with layers of clouds that may or may not contain ice, rapidly changing visibilities and questionable runway conditions tied in with a lot of night flying. Even in decent VFR, snow showers can suddenly reduce visibility to nearly zero, and while it is usually possible to pick one's way around the showers, they can prevent a pilot from proceeding in the direction of the destination. That means the pilot has to have a couple of potential alternate airports in mind if a diversion is needed, and that those alternates must be within the aircraft's range.
Because wintertime winds can be very strong — and their intensity can vary greatly with altitude — paying close attention to winds aloft forecasts and obtaining actual wind information, when available, can make a big difference in the length of your trip or whether you will arrive with adequate fuel reserves. It is not unusual to see a change in wind velocity of as much as thirty knots in five thousand feet of altitude. Also, it occasionally happens that there is a significant variance in direction even if the velocity is nearly constant. A little planning and keeping track of things while en route can be time well spent. And don't forget that other pilots need this information, also. Giving a PIREP to "Fright Service" every now and then can help someone else make a more-informed decision, whether before launching or while en route.
The more-experienced pilots and some of the guys who had taken survival training all said that it is wise to wear your warm clothes while flying, not take them off. Should you have to make a forced landing, you won't have time to put on the warm stuff. These experienced cold-weather pilots also carry at least a sleeping bag and some water in the airplane as basic survival gear. Most have complete survival kits for cold-weather operations.
One comment from a knowledgable pilot was that it makes no more sense to fly in winter without a survival kit than to skydive without a reserve chute, as the chances of survival are slim if something goes wrong in either case. I was also pointed to a very good Web site for aircraft and pilot survival kits and information: www.equipped.org maintained by well-known aviation writer and former AVweb news editor Doug Ritter.
All of us agreed that, when it's cold, pilots tend to hurry the preflight. Lots of things can go wrong: Components are more brittle, hoses crack, liquids freeze. A very brief bit of freezing rain, leaving not more than a few frozen drops on a parked airplane, can mean the static sources are plugged, leading to a loss of airspeed indication after takeoff, something that happened to me once in a Grumman Cheetah. A hurried preflight means that the chances of missing something are way too high. The rule of thumb is that when a pilot feels the urge to hurry that is a red warning flag to slow down, to take one's time. And, it sounds silly, but, as your mother told you, bundle up. Dress warmly so that you can spend enough time on the preflight to make sure everything works.
Get organized before you walk to the airplane. Have your maps folded, your paperwork the way you want it and generally make sure that you don't have to futz with stuff once you get in. While you sit in a cold airplane, before startup, you are fogging and freezing up the windows. The defroster may not be able to deal with that, particularly on the sides. Spotting traffic can be a bit of a problem with frosted-over windows.
As you approach an airplane parked outside, examine it closely for any snow, ice or frost. It should go without saying that any contamination must be removed from the wings, tail and fuselage before even thinking about starting the engine. Large accumulations of snow should be swept off with a broom, taking care not to damage control surfaces or antennas. A short ladder can help. Smaller accumulations and stubborn spots, including ice, should be dealt with by either rolling the bird into a heated hangar or by using deicing fluid. If you plan ahead, many FBOs will be able to put the plane in a hangar overnight — for a fee, of course. If none of these options are available, remove any remaining frost or snow with your glove or with an old rag — it's better on the paint than an ice scraper or a credit card. Take care to ensure that there is no snow, ice or slush in the gaps between control surfaces. Even if it's warm enough to melt this stuff on the ramp, it will likely freeze at altitude, and in the worst possible location at the worst possible time.
First thing on the preflight, after opening the door, is to put the ignition key on top of the panel so you and others can see it is not in the ignition. Then, turn on the master switch to see if you have electrical power. Do not drop the electric flaps, as you may need all of what may be limited battery power to crank the engine. You may discover that it is so cold the battery won't function. Bush pilots learned long ago to pull the battery out of the airplane after the last flight of the day and take it inside. In fact, when Cessna designed the 208 Caravan, its battery mount was made so that a person can pull the battery out in a matter of seconds to get it in where it's warm. Under very cold conditions, you may have to take the battery out and haul it inside to ensure that you'll have enough power to crank the engine. If the battery solenoid is too cold, it won't function either. I've watched resourceful pilots use a hair dryer to warm it up. It works.
If fuel won't drain from a quick drain, the drain is frozen. Therefore, there is water in some form in the fuel system. No, you are not going anywhere until you get that one solved by a mechanic. You don't know where the water/ice is. The risk is simply too high. An engine failure due to ice in the fuel system could well delay your arrival at Grandmother's house, and ruin her whole day.
If you have pulled the airplane out of a hangar or off a tie-down, turn it 90 degrees before starting. It is extremely poor form to run an airplane with the tail pointing at a hangar (once you have swept one out you'll never do it again). Blowing snow into one is inexcusable. Blowing snow all over someone else's airplane can be dangerous. Expect that the snow will get to where it can cause the most harm.
If the airplane is in a heated hangar, then you have the best of all worlds. You can preflight in comfort, board and be towed out. Before you are towed out, again, make sure you are completely organized so you can hit the starter once the tug crew has removed the tow bar and gotten clear of the airplane. You may want to open a window as you are pulled into the cold air to keep the windows from freezing over due to condensation. The sooner you can start and get the defroster operating, the less likely the windows will freeze over.
If the airplane has some sort of oil sump or engine heater, great. If you were on top of things, you went out the previous evening, lugged it in and put a cowling cover or sleeping bag over the engine room. That way, the oil will be nice and warm and starting will be much easier. There are those who advocate plugging in the engine heater when it first gets cold in the winter and leaving it plugged in. And, there are those who say only to plug it in the evening before a flight, as there is an increase in condensation and resulting corrosion from the use of heaters all the time. I have not seen any data on either side of the matter, so I do not have an opinion. If someone has data, not an opinion based on one or two events, I'm very willing to listen and I'll do my best to pass it along.
If you have a plug-in engine heater, then you might consider a very small cabin heater as well. There are a number of little heaters that can be used in the cabin to cut the chill. Of course, the idea is to avoid catching the cabin on fire, so make your selection of heater carefully, and spend some time considering where it can be put in the cabin. Some need at least three feet from any objects. That rules out their use in an airplane cabin. On some six-place airplanes, it is necessary to remove a seat to use a heater. On four-place airplanes, some folks rig a platform in front of the rear seats and fold the front seat backs forward. The idea is to keep the gyros warm. A general rule of thumb is that a vacuum-driven gyro is not reliable until it reaches 40 degrees F. On a cold winter morning, you don't want to punch into the clag with gyros that haven't gotten their act together because they are cold.
There are some "preheaters" which consist of large light bulbs in cans with fans behind the bulbs. The unit is hung on the spinner with the lights in front of each air intake. The heat goes into the engine, slowly but surely. They are not expensive and seem to work pretty well unless the temps are below zero F. It takes two to three hours to warm the engine, but they work gently enough that placing them in the cowling inlets should not be a problem.
If you need to use a portable propane preheater with flexible hoses, do so with caution. Those things put out a heck of a lot of heat. Localized heat. Pilots have learned the hard way that putting the hoses into the cooling air intakes in the cowling can melt or deform some valuable parts of the engine compartment and the cowling, leading to problems later on. As a result, put the hoses in the bottom of the cowling, where the cooling air normally escapes. You will heat up the oil sump a little better and the heated air will flow more evenly over the engine.
Keep a close eye on things. You may want to move the prop gently to see if things are freeing up in the engine. (See why I said to put the key on the top of the panel so you know it is not in the ignition switch?) Make absolutely sure the mags are off, but treat the prop as if the engine is going to fire when you move it. Carefully touch the cylinders to see if the engine is starting to warm up.
About 20 minutes is the most you should use a propane heater on an engine. That should be enough time to warm things up adequately. Check that the propeller can be pulled through by hand. At that point, on an airplane equipped with a primer, have a helper give you five or six shots of prime as you pull the propeller through, then leave the primer knob out. You will need it during the start.
Quickly pull the hoses out of the bottom of the cowling and move the preheater out of the way, but watch out for the hoses, they get extremely hot. I mishandled a hose one winter morning and, without realizing it, melted a hole in my down jacket. After I had gotten into the Arrow and started it, I noticed the cabin was full of feathers. Some duct tape took care of the jacket, but cleaning that cabin took some time. My wife still laughs at me about that one.
Once the preflight and preheating are done, get in and start up. Don't mess around with maps, or headsets, just fasten the seat belts and run the start checklist. I don't know how many times I've watched pilots load everybody in cold weather, then fiddle with this, that and 27 other things while the windows develop a half inch of frost, the engine cools off again, and then won't start. Once the engine has been primed and the airplane is ready to go, start it. When it fires, move your left hand from the starter to the primer and start pumping, but give the primer time to fill each time you pull it out. Do not, not, not pump the throttle more than once. (Some of the carbureted Lycomings seem to require one full cycle of the throttle prior to hitting the starter, but no more than one.) All pumping the throttle does is flood the carburetor, and when (not if) the engine backfires or afterfires, you'll light that fuel and have yourself a nice little fire.
(If you do get a fire, continue cranking the engine until it either starts or the battery goes flat. If it starts, the fire will go out immediately and there will be little, if any, damage. If it does not start, get a fire extinguisher and put out the fire. Ground the airplane as there will probably be some damage.)
Keep the engine running initially with the primer, positioning the throttle so that the rpm stays below 1000. It may run rough for a bit as the cylinders individually decide that they are in a reciprocating mood. There is not much oil getting to the places where it is supposed to be, so there is a whole lotta scraping going on. Make absolutely sure you do not let the rpm get to or above 1000 until you have definite oil pressure. This is not the time to start and go to 1700 rpm unless you want to buy yourself an engine or drive up rental rates substantially. While shooting a pilot who abuses an engine by starting at high rpm on a cold day is illegal, flogging him may be defensible.
When the engine smoothes out, lock the primer. Hold the brakes, keep the rpm low, and take care of the tasks you need to do such as headsets, radios, maps, etc. Make sure the defroster is all the way on, as even though the air coming out is cold at first, you need to keep it moving to avoid frosting up the inside of the windows.
Taxi And Takeoff Considerations
If you are wearing boots, make sure you can work the rudders and brakes through full travel, and that you can work the rudder pedals without hitting the brakes inadvertently.
Naturally, check the brakes right away. If there is snow or ice on the taxiway, go more slowly than normal and be certain to hold the correct aileron deflection for the wind. On a slick taxiway, you may find yourself almost sailing the airplane, so make use of the aerodynamic controls in winter. If you taxi through any snow assume that it is going to melt on the brakes and then freeze as you stop. If possible, try to plan your movements so that you have to use very little or no brakes at all. Stay on the center of the cleared area of the taxiway, but do not roll off onto soft ground doing so. As the wind blows and snow drifts, the painted centerline of the taxiway is rarely the center of the area between snow banks. Try to avoid rolling a wheel through loose, drifted snow as you attempt to keep the nosewheel on centerline. You will make a quick turn toward the snow and may find the prop cutting into the drift. Not fun, and sometimes expensive.
Be ready for ice at any time. Yes, the FARs require controlled airports to disclose the location of ice on taxiways and ramps. No, the locations are not always given. You are the pilot in command, so be ready for anything. At night, what is called "black ice" can eat your lunch. It is smooth and virtually invisible.
How treacherous can black ice be? Consider this true story: A friend was taxiing a 747 when he encountered unreported black ice at the end of a taxiway where he needed to make turn to the runway. He was doing less than 15 mph because the antiskid did not activate (it doesn't start working on that airplane until the airplane is moving faster than 15 mph) so every single wheel locked up. All my friend knew was that he turned the steering tiller without effect. He then hit the brakes. Nobody home there, either. In ponderous, slow motion, with four engines screaming in reverse, he went off the end of the taxiway and started down a hill before an engine pod hung up on a snow berm and stopped the show. He justifiably thought he was going plenty slowly. Black ice can be about as nearly frictionless as anything found in nature.
When you do the runup, make sure the tail isn't pointed at a building or another airplane so that you don't blow snow where it shouldn't be. You may clog someone's air intake or have the snow stick to and obscure a warm windshield, necessitating that the pilot shut down and get out to clear it.
Try to do the runup on a dry spot so you don't slide. Any time you have the throttle above dead idle, be looking outside as the airplane may be moving. Having the power at 1,700 rpm for the mag check while you put your head down to recite mantras is a poor way to discover you need a prop overhaul after you slid into a snow bank. Accordingly, keep the runup short. It is a time when the airplane can move unintentionally, so bring the power up, check the mags, prop, the alternate air/carb heat, eyeball the engine gauges and suction, then get the power back. There is no need to cycle the prop three or five times; if it works on the first cycle, the oil is circulating.
On some airplanes you may not have any indication of oil temperature before takeoff, or, for that matter, the entire flight. Refer to the POH or Owner's Manual as to whether oil temperature is needed before takeoff. For some aircraft the engine is considered ready to go when it will accept a smooth application of power (idle to full throttle over a period of at least five seconds) without stumbling, backfiring or quitting.
After the runup, assume that at least one brake will be frozen. So, have some room to maneuver as you add power. If the airplane does not roll freely, slowly continue to add power, being ready to bring it to idle. Most of the time the brakes will free up with a noticeable "bang" as the ice breaks, at somewhere around 2,000 rpm (of course, this was after you couldn't get the airplane to hold still during the runup). Keep the airplane moving and take off. Try to avoid stopping again, because you now have moisture on the brakes and they are likely to refreeze. They will probably also freeze after takeoff. This is usually not a serious problem, but it is something to keep in mind on landing.
On the takeoff roll, bring the power in smoothly over a time of five-to-ten seconds. Keep the airplane tracking where you want it to go, as drifting snow may mean that you have to dodge and weave a bit to stay in the center of the open areas. If you run one main gear wheel through some snow, as little as a half-inch deeper than the other wheel experiences, the airplane will swerve. It may be violent, so be ready with the rudders. It may take rapid rudder pedal application, perhaps to the stop, to keep the airplane straight. On a tailwheel airplane, hitting loose snow has the added attraction of pitching the nose down abruptly. Therefore, once the tail is up, keep it low, so the thrust line of the airplane is upward, not purely horizontal. If the runway is slippery, keep the aileron correction in for the crosswind and accept that you may actually accelerate the last few knots to rotation speed sliding crabwise if rolling control is lost. You will have to point the airplane into the wind to keep it traveling in the desired direction.
In retractable gear airplanes, do not be in a hurry to suck the gear up after breaking ground. Give the wind time to blow snow off and dry the gear to lessen the potential for frozen brakes or freezing the gear in the wells.
This is where it all pays off. On those blindingly clear winter days it almost seems you can see into tomorrow. The snow scenes would make Currier and Ives jealous, and you can change them at your whim, making each better than the last. Those green fields of last summer sleep beneath their winter quilts, highways seem less of an intrusion on the landscape and the shabbiest town looks beautiful when snuggled in the snow.
Check your power setting charts. In cold weather the engine develops significantly more power at a given altitude than on a standard day. You will see very high indicated airspeeds, mostly because it is cold, but partially because the summertime setting of 2,500 rpm at cruise was generating significantly less power than on a cold day. For example, in a Cessna 172N, at 4,000 feet on a warm summer day, 20 degrees C above standard temperature, 2,500 rpm is 67% power. At the same altitude and rpm setting on a day when the OAT is 20 degrees C below standard temperature, it is developing 76% power. Those who do not like to run their engines at above 75% power may be in for a surprise on a winter day.
In most airplanes, the cowl flaps can be closed completely at cruise and throughout letdown on cold days.
A discussion of structural icing is for another time. In very cold weather, it is not a problem, although flying in snow may plug up your engine air inlet necessitating the use of carburetor heat or alternate air. Those who are scared spitless of structural icing have a good, healthy attitude toward the stuff. I keep remembering the article in Flying magazine some years back by a guy who claimed he could always find a way to go no matter how much icing was out there. By the time the article came out, he and a noted politician were missing and presumed lost on a flight in which icing was forecast to be significant. They have never been found. I still think of overconfidence and icing and shiver.
The data is still being developed on whether "shock cooling" or a sudden power reduction really hurts most engines. From a conservative standpoint, until I know for sure, I try to avoid cooling an engine quickly. This is difficult on a cold day. For those who fly retractable gear airplanes with very high gear and flap speeds, tossing out the gear while at cruise, just before the descent, is a great way to come down and slow down while making very gradual power reductions. For the rest of us it is necessary to plan the descent way ahead of time. For airplanes with a constant speed prop, the generally accepted rule is to make a two-inch manifold pressure reduction and wait two minutes before making the next two-inch reduction. The idea is to get to pattern altitude about a mile from the airport at or below landing gear extension speed. That is hard to do. You may make those slow power reductions, then find, as you near the airport, it is necessary to climb some to get down to gear speed. That is a bit inelegant but works in VFR conditions. In IFR the controller may frown on a climb of any sort. In cold-weather IFR it is wise to negotiate with controllers for a descent as early as possible so you can make power reductions gradually.
If there is an overcast and snow on the ground you can experience what is known as "flat light." This can cause a complete loss of depth perception. Until you experience it, you simply can't believe it. Twenty-foot tall snow piles on the sides of runways appear to be completely and totally flat, level with the runway. Because one doesn't realize it is happening, and because there are still some snowplow drivers out there who are boneheaded enough to pile snow at the ends of runways, rather than the sides, do not aim for the numbers on a normal landing in winter. There may be something sticking up you just can't see. A lot of pilots have hit snow piles at the ends of runways at night and in flat light conditions, so aim a few hundred feet down the runway (remember, runway lights are 200 feet apart).
If it is snowing, or has snowed recently, call ahead about runway conditions. In areas that are not used to a lot of snow, there is a disturbing tendency for airport managers not to start snow clearing ops until the snow stops falling. They have not caught on that delay makes for a lot more work and extends the time the airport is closed. Good operators start clearing runways when the first flake falls. They may have a runway closed briefly while plowing, but usually get things opened up in less than 15 minutes. If in doubt en route, ask ATC or Fright Service to check with the airport beginning when you are about two hours out so you are not surprised on arrival.
Be especially careful landing just before dawn. For some reason, the information on runway conditions is not passed along very well about this time. I don't know if it is shift change or a result of airport managers who want to advertise their airports as open when they aren't. I recall a King Air crew who was advised that their destination was above ILS minimums, snow was falling lightly and that the runway had been plowed with two inches of packed snow remaining. About one-half hour before sunrise, they shot the approach, picked out the lights, and touched down some six feet right of centerline. Immediately, the crew heard a loud bang, the left wing dropped and the airplane started to turn left. The captain went to full right rudder, reversed the right engine, and, with alert assistance from the co-captain in the right seat, got the airplane stopped straight ahead. On getting out of the airplane they discovered the left half of the runway was plowed to nearly bare pavement. The right half was untouched. There was a two-foot tall pile of snow, on centerline, the length of the runway. Their left main landing gear had hit the snow pile and failed aft, but was still hanging on by bits and pieces.
Plan on touching down on the center of the open area on the runway. Doing so may or may not equate to the painted centerline if there is drifted snow on one side of the runway. Assume that the brakes are frozen, so you will not be surprised. If they are, you will hear the tires slide briefly, then two bangs and the wheels will roll normally. During the slide, the airplane may swerve or fishtail slightly. If only one brake is frozen the airplane may turn toward it at a rate which varies depending on the available friction. You can generally overcome it by using opposite rudder and brake. Yes, if you lock up the other brake you will have roughly the same friction on each side. That is rarely necessary, although it does happen, and folks who have experienced it say it works. I also have one friend, an instructor, who got too complacent with a student. They landed well off centerline with one brake frozen. Neither he nor the student reacted fast enough, so the Cessna 150 went into the snow bank and flipped. He is more alert, now.
Try to get braking reports before landing. For most general aviation singles, we can touch down slowly enough that we can stop on a pretty slippery runway without too much trouble. However, if you hear the word "nil" used to describe braking, use another runway. You probably will not have enough available friction to deal with any crosswind at all, and may not be able to stop no matter how long the runway. Don't forget braking action refers to friction, so a slippery runway in a strong crosswind can be more adventure than you need that day.
There are sophisticated braking measurement devices used on larger airports. These braking action reports provide a GA pilot with a lot of information and, particularly in twins, help decide if there is enough runway on which to get down and stopped, keeping in mind one does not aim for the very end. Even with all the fancy braking measurement devices, I'm still sort of partial to the measuring technique where the airport manager got in his pickup, drove down the runway at 60 mph, then stood on the brake. If his lunch box fell of the seat, braking was good.
Instrument Approaches In Snow
Snow can reduce visibility to nothing in seconds. This can occur while on the approach, in the flare or on the rollout. It is not uncommon to reach decision height or get to the missed approach point and not see anything, then begin the missed approach and suddenly see the runway about 400 feet directly below you. There is a gigantic temptation to get a quick clearance to circle to land and try and wrap the airplane around tightly to the runway. To put it bluntly: Don't. You won't make it. Four hundred feet of vertical visibility in snow simply doesn't equate to 400 feet of horizontal visibility in snow. You'll be wasting time and fuel, plus attempting one of the most dangerous maneuvers in instrument flying. All of the circle-to-land approaches I know need at least 5,280 feet (one statute mile) of horizontal visibility. Keep climbing out and proceed with the missed approach procedure.
A few of the pilots in the lounge described exciting excursions during rollout on runways that they thought were in good shape. Their recommendations boiled down to not being in a hurry to get wing flaps up or cowl flaps open or lights off or anything until you have that airplane hauled down and turned off the runway. In the winter you simply never know what the condition of the next foot of runway is going to be. Keep all the aileron for a crosswind cranked in, and be ready to add power at any time to get control or go around, if things don't feel right.
After clearing the runway, take care of housekeeping chores and taxi carefully to parking. Keep in mind that the last area to get plowed on many airports is the general aviation ramp. If you have to get through some untouched snow, keep the yoke all the way back and the power on, so as to avoid coming to a stop, if possible. If you cannot maintain directional control, chop the throttle, stop and shut down. It's a lot less embarrassing walking the last hundred yards to the pilot's lounge and asking for help getting the airplane in, than it is doing that same walk and then having to say you hit something.
Once you have shut down, go through your usual securing checklist, then put on covers or plugs as the case may be, plug in the engine heater if you desire, and do a post-flight walk around. Check the airplane for any dents from chunks of ice you might have kicked up and for any leaks from a split fuel or oil line. A quick post-flight inspection may uncover a small problem before it becomes a big one.
Should We Fly In Winter?
As the discussion proceeded, I thought of the things that can go wrong, and began to wonder if the old barnstormers who worked the northern states in the early 1920s had the right idea. They knew that if they went south for the winter, the oversupply of barnstormers meant everyone would starve, so they found a shed, put their airplane on sawhorses, drained the oil, rented a cheap hotel room, lined up a bootlegger and hibernated.
Naw, no bootleggers around anymore.
Winter can provide some of the most enjoyable and scenic flying you ever do, but it does present challenges. In general, the consensus of the folks here in the pilot's lounge was that if you are pretty conservative with weather and allow extra time to get things going at the front end of the flight, it is a delightful experience.
Yes, it was a good day. The blizzard the weather gurus have been forecasting is due soon. It's already snowing and starting to blow. I'm heading home. If I know anything about cold weather ops it is that when it's cold enough to freeze a dog to a hydrant and the snow is horizontal, it is much better to be down here wishing I were up there than the other way 'round. See you next month.