Page 10 - Jan24T

wheel wells, flaps, and control surfaces where it can freeze. If f laps are used for takeoff, delaying f lap deployment until taking the runway will eliminate frozen contaminants obstructing retraction mechanisms. After takeoff, delay- ing gear and flap retraction and allowing contaminants to blow away is a useful best practice.
Once airborne, listen up on frequency to hear what con- trollers and other pilots are saying about the conditions. Base and top reports are the best way to understand the weather in your sector and, along with your OAT gauge, will indicate when icing could occur. Take the initiative to ask ATC; if no reports are available, be responsible and give them accurate reports of what you are experiencing. The next pilot through that airspace will surely appreciate it. You should activate propeller heat, windshield heat, hot plates, etc., before entering any potential icing environ- ment and always by the POH or AFM.
Icing will adhere to small protuberances before larger ones, so pay close visual attention to those areas of your airframe. The windshield wipers would be my first indi- cation of icing in the Navajos, Cheyennes and King Airs I once flew. A high-intensity flashlight will help you see these unlit areas in darkness and is a great backup in case wing inspection lights fail.
A pilot exercising sound risk management will give himself three outs when icing conditions occur – verti- cally, either up or down, and if that fails, the ability to reverse course out of the icing event. In general, icing layers are relatively thin - only a few thousand feet thick and in most cases, climbing through or descending to a lower altitude will do the trick.
Beware if trying to climb through an icing layer, though. As ice accumulates on any airframe, the significant in- crease in drag can deteriorate the aircraft’s ability to climb. Depending on the accumulation intensity, expect higher than normal climb power settings. Aircraft sometimes run out of climb performance and, in some cases, the ability to maintain level flight. In this situation, if there isn’t enough terrain clearance to descend, the only out is to reverse course and exit the icing area from where you first encountered it. Do so calmly and carefully as the lift further deteriorates in turns, raising stall speed. When descending through icing layers, try to do so ex- peditiously and at as high an airspeed as practical, as ice accumulates less as airspeed increases.
Once entering the terminal area, the combination of being close to the ground while flying at slower airspeeds increases the risk in icing conditions, making it the most dangerous phase of flight. If you expect icing, activate all heated surfaces before beginning an approach, espe- cially before entering this high-workload environment. If leading-edge boots have been activated, another cycle on and off is a good habit to adopt. Should you be required to enter a holding pattern in potential icing conditions, do so at a higher airspeed and refrain from extending flaps until they are required for landing.
During the approach and landing phase, tailplane icing becomes a significant factor to consider and manage safely. Tailplanes will collect ice earlier than wings because of their thinner profile. Compounding that problem is that most tailplanes are not visible to the pilot, so precautions must be taken. On most aircraft, tailplane ice accumula- tion can cause a nose-down moment as the center of lift
8 • TWIN & TURBINE / January 2024