October is a month of change. The tourists are gone and the shops that cater to them closed. The kids have been back in school and are deep into their winter routine. Our weather is getting colder and we are getting out the winter clothing. Oil in the car needs to be changed, and speaking of oil what about winterizing the airplane.
Some suggestions that came from an airworthiness inspector in the office might be beneficial to your aircraft. Drain the oil and put new oil in before storing the airplane. Acids build up in oil as it is used and could damage the engine. Take the spark plugs out of the engine and spray the pistons with a lightweight oil product, then replace the plugs. Leave gas in the tank topped off to prevent moisture condensation. In a cold climate, especially near salt water, it is a good idea to cover the engine cowling to prevent corrosion from forming. Clean the prop and put on a coat of wax to protect it from corrosion. Resist the urge to run the airplane engine during the winter. The oil that you put in at the beginning of winter becomes used oil and therefor acidic.
Check the fuselage for leaks around doors and windows. Mildew can form and can be a mess to remove. Water seeping in can ruin radios and upholstery. When water freezes it can cause unnecessary expensive repairs. Cover the airplane if it will not be in a hangar for the winter. Damage can result from snowloads that are not removed over the course of the winter.
If you are flying this winter, be careful to remove all snow and frost prior to flight. Frost and ice on the leading edge of a wing or tail surface can reduce or destroy lift altogether. Sweeping the surface with a broom works on dry snow but has little or no effect on frost accumulation. You can polish frost to a smooth surface, but as a precaution it is important to follow the instructions in the aircraft manual. Warm water can be used to de-ice if you dry the control surfaces sufficiently to prevent the hinges from freezing in flight. Concentrated de-icing fluid can be purchased and after diluting it may be applied with a hand sprayer.
Before every flight be sure to check the control surface travel. Full deflection will confirm that no ice formed at the hinge-points. Follow the manufactures suggested cold start procedures. Some pilots over-prime engine to thin the oil before start. It might work but could cause a fire. Know where your fire extinguisher is located and be certain that you understand how to use it. Pre-heat the engine on exceptionally cold days using an approved pre-heating method. Engines and accessories have been destroyed as a result of the improper application of pre-heat.
When you do fly on those cold crystal clear days we have in the dead of winter, be sure to get weather updates. Be prepared and enjoy the beauty of Southeast Alaska covered in glistening snow.
Patricia Mattison is the safety program manager for Juneau Flight Standards.