Those of you flying in winter might hope for the best but you know to prepare for the worst. Although the season’s cold dense air often produces more favourable atmospherics for thrust and performance, tackling the variability of winter temperatures that span the US continent requires keen flight planning, not to mention additional precautions to mitigate any rapid or unanticipated changes in weather conditions.
Frost alone can reduce your wings’ maximum lift by up to 30% and increase drag by up to 40%, and ice and snow can be deadly. Between 2007 and 2017, 52 general aviation accidents were caused by structural ice, resulting in 46 individual fatalities and 7 serious injuries.
Your TKS system is the most reliable ice protection system on the market. To ensure it continues to provide you with the highest level of protection, here’s our TKS checklist to keep you flying throughout the winter months:
▣ Run your TKS System regularly
Running your system every 30 days keeps the moving parts lubricated and the lines and panels relatively charged, as well as enabling you to identify any potential issues in advance.
▣ Clean your TKS Panels
To clean the panels, use warm water, mild soap and a lint free cloth, or a green scouring pad for dirtier jobs. When panels are extremely dirty, turn the system on and clean as the fluid comes out, as this will help to dislodge any debris caught in the panel holes.
To prevent damage, always clean the panels with a chordwise motion and only use the following solvents:
Water with soap/detergent
Approved TKS Ice Protection System fluid
Industrial methylated spirit
▣ Check De-icing Fluid Filter
The de-icing fluid filter element should be changed at 1200 hours or two-year intervals.
However, the filter element may require changing at more frequent intervals, depending on service conditions and fluid handling equipment when operating in localities where there is an excessive amount of sand and dust.
▣ Fluid Quantity
A minimum of 1.0 gallon is required in the tank before take-off if the system is to be considered operational.
For maximum head pressure to pump inlet, ensure tank is full and that all system components are filled with TKS fluid. If necessary, operate pump(s) until all air is dispelled from components and pipelines.
Always be certain you have a sufficient quantity of TKS Ice Protection fluid in the tank to complete the intended flight.
▣ Prime your TKS Panels
The TKS Ice Protection System needs to be primed prior to any flight when you might encounter ice, and should be primed every 30 days to prevent becoming air locked.
Turn the system on and let it run until the panels are completely wet. Once operating pressure reaches the normal operating range, the light on the control panel will change from red to green; this can take up to 15 minutes.
If the panels do not wet out, you may need to have them purged due to being air locked.
▣ Prime your TKS Pumps
Operation of the self-priming windshield pump pulls fluid through the system pump(s) to prime the system.
TKS Ice Protection Systems for certain aircraft have a windshield pump attached to an equipment pack to pull fluid through the main pump automatically upon start up but if this is not that case:
· Ensure tank is full of TKS fluid for maximum head pressure to pump inlet.
· Disconnect supply line at the pump inlet and allow fluid to flow until clear air free flow is obtained.
· Reconnect supply line and bleed air from the pump body by operating the windshield pump.
· Remove the air bleed screw from the filter housing or main body of filter element, and switch on the airframe/propeller pump.
· Allow the pump to run on “De-Ice” until clear air free fluid is emitted from the filter bleed.
· Switch off the pump and replace the bleed screw.
To ensure faultless operation, your pumps should be overhauled or replaced as per Section 8 of your aircraft’s Flight Manual Supplement.
▣ Pre-flight procedure
A full pre-flight inspection of the system ensures that if any ice is encountered in your flight, the system is ready to operate immediately to clear it.
A full pre-flight consists of running the pump while you do your normal aircraft pre-flight and upon completion, you should have evidence of fluid on all the panels. This means the self-contained reservoir in each panel is filled and you should have instantaneous protection. It is very important to follow the TKS Ice Protection System pre-flight procedures outlined in your Flight Manual which includes:
1. Battery Switch ON
2. DE-ICE ON
3. Airframe Inspection:
Fluid Tank – Check quantity, Check Cap Secure
Porous Panels – Check condition and security – Check evidence of fluid from all panels and propeller
4. All switches OFF
Before Starting Engine
1. Fluid Quantity Indicator: Check quantity (see limitations for weight and balance)
2. System Operation Lights: Check operation
3. Windshield Deice Pump: Check operation
4. Wing Inspection Light: Check Operation (Check OFF if daylight operation)
5. All switches OFF