Many people who have anxiety about flying seldom understand the complexness of aircraft icing accidents. Aircraft icing can be a hazard to aircraft if you have lack respect for it. Most modern commercial airplanes are approved to fly into icing conditions. In order to fly into icing conditions, you need engine anti-icing system, wing airfoil anti-ice, fuel heat to melt ice in the fuel lines, windshield heating, & various heating systems for certain instrument indications in the cockpit. It's important to know that icing don't happen in perfectly clear blue skies no matter how cold it is. You need two things to pick up in flight icing. You need visible moisture in the form of clouds, drizzle, rain, or fog.  You also need to be in a specific temp range from +5 degrees Celsius to -15 degrees C. In flight icing is further described on a scale range from light, moderate, to severe. No aircraft will be able to sustain level flight in severe icing conditions. Severe icing means that the aircraft's anti-icing system is basically ineffective. For fearful fliers, its important to know that in the rare cases were there is an airline accident that involves icing conditions most times its usually bad pilot judgment, or someone not following basic safety operating practices.