Briefing

Planing

Flight-planning prior to any flight is mandatory and extremely important . Both weather information, shooting lists, etc. must be gathered for a safe flight to be carried out. Especially during night flying and instrument flight rules, a lot of information must be obtained to execute a safe flight.

Links to various sites for use in planning:

A "pinto-board" is a handy office tool when flying:)

Winter flying

Winter flying requires a lot of extra preparation and attention compared to flying in the summer, especially when the winter weather brings snow, sleet or other precipitation combined with cold and frost. For safe flying, it is important to have a thorough knowledge of meteorology and the weather phenomena that occur at this time of year, which can typically cause problems or, in the worst case, accidents in connection with flying, e.g. Airframe icing, contaminated runway, carburator icing etc.

Pre-flight and planning: check weather with e.g. Dmi and interview with meteorologist so that all information is collected for departure-enroute-destination/alternate (Metar/TAF/Lowsig-map/notam-snowtam...and Sigmet). Are there front systems on the route, possibly clouds what type and at what altitude, zero degree at what altitude, wind and especially cross-wind component combined with snow and ice on the runway at destination. Calculate take-off and landing distances taking into account ice/snow on the runway. Check pilot operating handbook for the relevant aircraft type around winter operation, is the type possibly approved for flight in known icing conditions (de-icing/anti-icing equipped).

Aircraft and ground handling: It is vital that the aircraft is free of snow and ice before flight. Snow is swept away from surfaces and it is ensured that there is a clear view through the windows. The best thing is that the aircraft can be parked in a heated hangar and make sure that any water from melted snow and ice has dried completely away, remember to drain any water from the fuel tanks as the water can freeze to ice in the fuel filters and block the supply to the engine. In very cold weather, the battery's capacity is reduced, the external light check can use so much of the battery's capacity that it will not be possible to start the engine. Starting the engine in cold weather requires extra priming to get the engine started. The tendency is that it gets too little fuel, but if you have over-primed it, the engine must be ventilated (ignition off- mixture off- throttle open) This start-up procedure involves a risk of engine fire - see section emergency procedures.

Maneuvering: Depending on the taxiway and the surface condition of the area, taxiing and maneuvering are done with caution, "pump" the brake instead of blocking (aircraft without anti-skid, however, wheels can also be blocked with anti-skid at low speeds). Pay attention to driving through snow drifts such as compacted/rolled snow, "invisible marking objects" when talking about "guidelines not visible" and there may not be clearance to the wing in case of reported critical snowbanks.

During the warm-up check, pay particular attention to any ice in carburetor. Take care that the airplane does not move at the high revolutions! If equipped with heated pitot this should be on before take-off!

-Take-off: Atis or meters for the airfield can contain information about precipitation and spread on the runway as well as braking effect (Motne code), without this information special precautions must be taken of the nature of the runway (contaminated runway) with regard to water/ice/snow/slush or ice, so that acceleration to lift-off speed will be possible within the runway available (Applies Impingement drag to the aircraft). In the event of an interrupted start, the braking distance will also increase significantly under the above conditions.

Start distance corrections according to AIC B 24/08. : http://www.slv.dk/Dokumenter/dsweb/Get/Document-9120/AIC_B_24_2008.pdf

Water or slush (max. depth 2.5 cm.) 20% per cm.

Wet snow (max. 5 cm.) 10% per cm.

Frozen snow (max. 10 cm.) 5% per cm.

-In-flight:

Ice can form when there is a certain amount of moisture or liquid water droplets in the air and the temperature is below 0 degrees. That is that aircraft icing cannot only occur in terms of flight in clouds. The most critical form of icing an aircraft can be exposed to is clear ice. When supercooled water drops, for example, hit the aircraft's wing which is below the freezing point, clear ice forms on it and depending on the temperature, size of the drops and the duration of these conditions, the icing can be characterized as either light, moderate or severe. Check wings at regular intervals for ice. Without de-ice/anti-ice protection, in the event of icing you should search down into warmer air (below 0 degrees) or away from areas with moist air (search towards the mainland/inland) so that . ice can melt. If it is possible during Ifr(IMC) to rise to the top of the cloud layer, this will be an opportunity to make the ice disappear.

During a long descent with the engine idling, there is a high risk of carburettor icing, remember to use preheat. Even with high external humidity and temperatures up to plus 27 degrees, ice can form in the carburettor as a result of normal pressure and temperature drop in the venturi tube.

Rim ice (whitish ice that typically settles on leading edges) and hoarfrost, which typically forms when descending from a cold layer of air into warmer, more humid air, are other types of ice that pose a significant danger to flight. What all these types of ice have in common is that they reduce lift, increase resistance, increase weight and it is extremely important to know that the ice can significantly increase stall speed. The stall warning can be unreliable with icing on the wings, so it is not certain that you will get this warning before a stall. Flying at Cu/Cb, fronts and inversions can pose a significant danger in winter. Other forms of icing can be ice in the air intake, propeller ice, icing of pitot tubes and windows as well as carburetor ice.

-Landing: If ice is suspected or detected on the wings/tailplane, increase the speed (to safe speed) and do not lower the flaps if there is ice build-up on the tailplane as this can cause a tailplane stall with an irreparable nose-down. Preheat carburetor before final to prevent ice build-up.

In the case of wet solid snow or wet ice, a 50% surcharge should be added to the landing distance

If dry solid snow or dry ice use 20%. In addition, the recommended safety factor of 1.43

Contaminated Runway definition: More than 25% of the runway is covered by standing water, ice, snow, slush or in another form corresponding to 3 mm or more.