Questions pertaining to the Air Operations Safety article, "How to Avoid Icing Conditions":

Transcription

1 Attached are the IAWG Staff Ground and Air Operations Safety Briefings for December You will also need to go to the National Headquarters site to read over the December issue of the National CAP Safety Magazine, "The Safety Beacon". You can locate "The Safety Beacon" by going online at the National CAP Headquarters site, then clicking on Safety, followed by clicking on Newsletters, then on 2011, and finally on December. Please read these articles and then answer the following questions pertaining to them and then the answers to me at so that I can acknowledge them and then post your name to the updated National CAP Safety Briefing Currency Report. Questions pertaining to the Air Operations Safety article, "How to Avoid Icing Conditions": 1. What is the first thing an air crew on the ground should do after an ice storm has dissipated? 2. What is the first thing you should do if you are so unlucky as to fly into freezing rain or ice by accident? Questions pertaing to the Ground Operations article, "12 Tips To Choose Winter Clothing": 1. What part of your body loses the most heat compared to any other? 2. What should you do at the first sign of excessive warmth? Questions pertaining to "The Safety Beacon": 1. What are three main facts about Christmas Holiday Fires? 2. What does the NTSB believe strongly in as to ensuring that aircraft wings are free from critical ice contamination? NOTE BELOW: Remember that both the Annual Safety Surveys and the Safety Down Day dates are due at Wing HQ by 15 December 2011!

2 HOW TO AVOID ICING CONDITIONS Many would contend that icing is the most serious weather condition that pilots can face as they fly through adverse weather. While not as monstrous as thunderstorms, icing is even more dangerous because of the insidious nature in which it can attack. A pilot can see a thunderstorm from miles away in most instances. In the rest of the cases, radar, ATC and other resources are available. In addition, a pilot knows when he is in a thunderstorm. The lightning, down drafts, updrafts, microbursts, and even mesocyclonic activity make them hard to miss. But icing is different! It is a sneaky killer. One minute you are flying along seemingly with no problems and the next you are plummeting to Earth in an uncontrollable stall. Ice accretion on the aircraft wings has destroyed their ability to act as airfoils and provide lift. As we all know, lift may fail; but gravity never fails! So what is icing? Basically, it is the accretion of ice on aircraft surfaces. That accretion can cause a variety of woes ranging from instrument failures to engine power problems and finally a total loss of lift. What are the parameters for icing? Luckily, icing can only occur in a very narrow temperature range near the freezing point. First, we need temperatures in the range of degrees. Any warmer and nothing will freeze. Any colder, the air does not have the ability to hold the moisture needed to form super cooled droplets. These super cooled droplets are able to remain in a liquid state, though they may be as cold as degrees. Icing, then, occurs in an optimal temperature range of degrees and when the relative humidity is such that it allows super cooled droplets to form in rising warmer air. These droplets can be anywhere from 30 to 300 micrometers across and their size will become important later. The final stage of icing happens when the drops freeze on the airframe and disrupt the flow of air. There are three types of icing. Why? Well it has to do with the tweaking of the icing parameters discussed above. Clear Ice forms when large super-cooled droplets hit the airframe, freezing as they spread along the surface. This allows a solid sheet of smooth ice to form on the airframe. There is a good and a bad point here. The good first since clear icing spreads as a smooth sheet on the airframe resulting in very little disruption of airflow. Unfortunately, this is out-weighed, literally by the bad: that clear ice is heavy and hard. It is the heaviest of all types of icing and the toughest to remove! Add enough of it to the airframe and lift is overcome by gravity with serious effects. You can expect to find clear ice in areas of rain and almost exclusively in cumulous types of clouds Rime Ice is formed when smaller, fast moving, super-cooled droplets hit the airframe and freeze instantly. They do not spread across the surface but freeze where the hit. As hundreds of these hit the airframe they trap air in pockets between each other. This gives

3 Rime ice a milky appearance, compared to clear ice. Rime ice is much lighter due to the air trapped within. But the rough irregular surface can be significantly disrupt the airflow over the wings and other control surfaces that control is impossible. Rime icing is common in areas with drizzle and usually in stratus type of clouds. Mixed Ice is just what it says, a mix of clear ice and rime ice. This is seen when droplets vary in size or when snow, various size droplets and ice pellets make up the mix hitting the plane. This is the most serious form of icing. It has the weight of clear ice and the airflow disruption of rime ice. It is a deadly combination, to say the least! We should also take a look at a couple of icing problems not directly related to control surface icing. Induction icing forms when super-cooled droplets are sucked into the engines. This can restrict the flow of air into the engine and even restrict the movement of engine components. Instrument icing occurs when pitot tubes and static vent ports are covered and closed with ice. This can lead to the loss or malfunction of a host of instruments, many essential to safe flight in heavy weather. So how does CAP handle icing conditions? We do not fly when icing conditions are forecast or are actually occurring in our areas of responsibility! All our aircraft stay on the ground and in their hangers when icing conditions are prevalent! And, we will continue to stay there until the icing conditions are gone! There are no mission or training requirements important enough to risk the loss of an aircrew or an aircraft. If you are going to operate an aircraft shortly after icing condition have dissipated and have moved out of the general area and CAP has authorized you to fly, please follow the following guidelines: 1. Before moving the aircraft, check the wing surfaces, control surfaces and the fuselage for any ice and snow build up and remove them immediately. Remember that the said accumulation will affect both takeoff and flight characteristics to the point of causing a loss of control. 2. Also check out the runways and taxi ways you plan on using, before you move, to make sure there is no ice or snow on them that could cause slippery conditions 3. Check the forecast one more time before you leave to make sure that the forecast hasn t changed to include icing conditions returning to the area you plan to fly in 4. Do not fly into or anywhere near areas that are forecast to have ice or freezing rain conditions 5. Constantly check the windshield, the propeller and the leading edges of both wings while flying, for any sign of ice accumulation. A shiny gloss is a good indicator of ice being formed on any surface!

4 6. Monitor your radios to listen for any icing conditions that may be reported by other pilots flying in your vicinity. And, if you should be so unlucky as to fly into freeing rain or ice by accident; first initiate your engine and pitot heating systems and use them to the best extent! Then try to avoid the icing conditions by turning 180 degrees to and by climbing above the precipitation or descending below the freezing line. If necessary, declare an emergency and do whatever is needed to fly out of the danger and get the aircraft down on the nearest airport.. At any rate, when you do run into icing conditions, make quick and accurate decisions that allow you to leave the area immediately as the icing can build up on your wings, fuselage and control surfaces in an instant. This can happen so fast that the aircraft can be out of control before you even have a hint that you are in an icing environment and this is one predicament you never ever want to ever be in!

5 12 Tips to Help You Choose Warm Clothes In a 4 season climate, its nice to know how to dress warmly enough to stay comfortable outdoors. Here are some tips for doing so. 1.Dress in layers. The more layers, the better. Dressing in layers of clothing does several things for you: Layers fill up the space between you and your winter coat with insulation. An undershirt, a shirt, and a sweater each represent one layer. Your winter coat is yet another layer. The more layers of insulation, the better. Layers tend to trap air better. If you have only an overcoat on, the warm air next to your body tends to leak out of the top and bottom of the overcoat as you make body movements. Layers help to hold this air in. Layers allow you to regulate your body temperature more accurately. If you get too warm, you can always open up a layer -- starting with opening up the top of your overcoat and progressively opening up more and more layers as you get warmer and warmer. 2.Favor natural materials. In my opinion, there is nothing warmer and lighter than a down overcoat. If you can, buy one that is rated to a certain temperature such as 20 degrees below zero Fahrenheit. 3.Don't get over-sold on synthetic materials. Synthetic materials often come highly recommended. Before you buy synthetic materials, however, be aware of the following: Wool will keep you warm even when it is wet. I know of no synthetic material that will do this. Natural materials tend to breath better. This can be critical when you start to work up a little bit of a sweat and need to evaporate this sweat so that you don't become cold later when you are a little less active. One exception is the value synthetics add as wind-breaking materials. It sometimes makes sense, for example, to have a pair of wool gloves (perhaps with leather palms for wear) covered by larger-thanyour size mittens that have a nylon shell. This will keep your hands very warm.

6 4.Be aware that you lose more heat through your head than any other body part. 2. This can be very deceptive. Your head never feels cold. Why? Because your body sends more heat to your head than any other body part to protect it. Keeping your brain warm is so critical that your body will sacrifice any other body part before it will let the brain get cold. Just because your head does not feel cold does not mean you are not losing heat off the top of your head. Remember this forever! You will not feel yourself losing heat off the top of your head, but you are! The reason your feet and hands are cold is because you are losing heat in the head area. Why? Because hands and feet are low priority and your head is top priority. This is the body's system for rationing its limited heat supply. Because your head is given top priority when it comes to heat supply, it never feels cold even though it is in fact a giant heat dissipation module. Remember! Your head leaks heat. Plug the leak. If you will prioritize keeping your head warm, you will have won half the battle in keeping your body warm. 5.The dumber your head-gear looks, the warmer it is. I was recently shopping at L.L. Beans. A man was looking at a bombardier hat with a leather cover and a sheepskin lining. A woman who appeared to be his wife said to him, "Forget it! You're not wearing it!" Grimly, he put it back. He had just barely started to look. The hat would have gone well with the character Jim Carey played in the film Dumb and Dumber. As dumb as it looks, it is also very warm. Yes, head-gear that dramatically alters your appearance is incredibly warm. The converse is also true. Cool-looking winter hats are just that -- a little too cool temperature-wise. Why do you think those Russian women wear those big fur hats when it's 20 below zero? Because fur is incredibly warm, that's why. 6.Keep your feet warm. Your feet are in contact with the cold ground. You should wear well-insulated boots. Again, favor natural materials. Wear wool socks if you can find them and layer them if necessary.

7 Sheep skin boots can also be quite warm Keep your neck warm. A scarf around the neck or a jacket that zips up to your neck will do. There are 2 important reasons for covering your neck: You want to leave as little skin exposed as possible. This is the obvious reason. A less obvious reason is that you want to seal the top of your jacket so that air does not leak out of the body of your jacket. You lose a lot of heat when the top of your jacket is basically an open hole surrounding your neck. If you were a boat, you'd sink. Patch up the leaks wherever you can. Be sure to buy a jacket that has velcro seals on the cuffs of the sleeves so that you get a tight seal against the cold around your wrists. 8.Prioritize! Decide in advance which body parts you wish to keep warmest. This was taught to me by a lady from Norway. She says that keeping your priorities straight will help keep you warmer. Some body parts are more important than others. Here is how I suggest you prioritize based on what I learned from her: First, you want to keep your torso warm. Second, your want to keep your head warm. Third, you want to keep your feet warm. Fourth, you want to keep your neck warm. Fifth, you want to keep your hands warm. Sixth, you want to keep your legs warm. By focusing on what is most important first, you are likely to stay warmer. Why? Because ignoring a very important priority area, such as the head, will make you cold very quickly. 9.Make sure you don't sweat. If you get too warm. you sweat. This is very bad. If you sweat, you get wet. If you get wet, you get cold. How do you avoid sweating? Make sure you peel off your layers as you start to get warm. A very fast way to cool off is to open up your jacket. Another is to take off your hat.

8 Anything that helps you to radiate heat will help you to cool down. Taking off your mittens turns 4. your fingers into radiator prongs radiating heat. Taking your hat off turns your head into one giant radiator prong radiating heat. The key is to stay on top of it. At the first sign of excessive warmth, start opening things up. Usually this happens when you are doing something that causes you to exert yourself, such as climbing a hill. 10.Keep your face warm by keeping the rest of your body warm. Yes, you can cover your face with a scarf or a face mask. Do so if it is cold enough and you have to. However, I find covering my face to be uncomfortable. I prefer to employ another tactic. I like to keep the rest of my body so warm that I can afford to lose warmth through my face. Think of it as a bank account. Warmth you preserve with other parts of your body can be spent on your face. Call this tactic saving face if you need an easy mnemonic. 11.Wear long underwear. Besides providing an extra layer, long underwear saves your legs if all you are wearing are blue jeans. 12.Buy a good winter coat. I've saved the best suggestion for last. Here are some of the features you want in a winter coat: Make sure it features down insulation. In spite of commercial advertising to the contrary, there is nothing warmer than down -- in my opinion. Make sure it is rated. My coat is from L.L. Beans. It is rated to 20 degrees below zero (fahrenheit). It is quite warm. You can do even better than this at a mountaineering store if you need to. Note that the ratings on coats are generally geared towards moderate activity. If you are planning on standing around gazing at the stars through your telescope, you may need to buy something that is even warmer. Make sure it has a hood. This is important because it represents yet another layer. You should wear both a hat and a hood if it is very cold. Ideally the hood will stick out in front of your face just like the hoods of Antarctic explorers you see in National Geographic. This traps air near your face. The fur lining that lines the hood is a further air trap. A natural fur can provide a further benefit; it reflects heat back to your face. Unfortunately for warmth, the fur on my hood is cotton and acrylic. Make sure that all openings on the jacket seal. This includes the top of the jacket and the sleeves.

9 There should be a pull string that lets you adjust the waist so that you don't lose air out of the 5. bottom. Buy a coat that is long enough. I special ordered mine in a long size. The racks in the store did not carry one that was long enough to suit me. Ideally, I want a winter coat to extend far down on my thighs and the sleeves to reach down to my hands. Conclusion How you feel about wintertime is largely dependent on how good a job you do of keeping yourself warm. It's a modest ambition -- wanting to stay warm. But it is very important to your wintertime morale. Written By; Edward Abbott, All rights reserved. Revised May 4, 2004.