TKS or no TKS

[leonard17F]

Hello Fellow PPruners !

May I ask you what is your opinion on TKS-based wing anti-ice system?

What are the pros and cons ?

For a Part 23 airplane, would you prefer Boots ? Or something else, more modern ?

Thanks a lot !

[Kelly Hopper]

I have flown the 125 on and off for 25 years. TKS is old for sure but it works. As long as you have a ready supply. Africa can be a problem. Take some spare. Other than that no problem. In the sim they want you to prime, prime and prime again. Yeah in an ideal world for sure. But away down route in africa for 3 months? No way! With the climb performance of the aircraft it rarely get used in anger so no real problems. A historic solution to the problem of icing but one with no vices?

[westhawk]

Both types of ice protection work well in my experience. But each has shortcomings.

The TKS system installed on the Hawker series requires constant use and testing to maintain readiness. It also does little good if it's not activated before icing conditions are encountered. In short, it takes knowledge and discipline on the part of both mx and pilots to be effective. The juice must be flowing a couple minutes prior to icing in order to provide proper anti-icing protection.

The pneumatic boot systems installed on numerous airplane types I'm familiar with also works well within it's limitations. The boots must be kept clean and damage free in order to work as expected. Several surface treatment options are available to enhance boot serviceability. Pilots must be knowledgeable and disciplined with regard to their limitations and use on the specific airplane type in order to use them safely. In spite of the information certain safety regulators may promulgate, not all boot systems and airplane types are the same when it comes to using boots effectively.

Both pneumatic de-icer boot and TKS anti-ice systems are effective within their limitations if properly used and maintained. They have also both been misused or ill-maintained and been factors in icing related accidents. The heated wing concept is superior in both regards, but requires a considerable supply of hot air or electrical power that many airplane types are by their design, not equipped to provide.

I personally find the boots to be marginally superior to the TKS system because the boots are used after icing is detected. Since TKS must be used before icing is detected, then it must be activated anytime icing conditions might be encountered. With a limited quantity of fluid available and the possibility of entering unanticipated icing conditions, I'm just a little more comfortable with the boots. Heated surfaces would be my top choice if choices were offered. Knowing the limitations and proper usage of whichever ice protection systems the airplane being flown has installed is the most important factor in determining it's effectiveness in providing protection in icing conditions.

The best use of ice is for chilling your cold beverages!

[Alpine Flyer]

On a side note I always wondered why the Dash 8-400 doesn't use some of the massive amount of power the PW150 would be able to deliver for de-icing the wings, rather than sticking to plain old boots like the -300.

[Capt Claret]

?.. DH8-400 ... for de-icing the wings, rather than sticking to plain old boots like the -300.

Possibly a certification consideration, as well as manufacturing scales of economy.

[Mansfield]

For the record, in 22 years of work with inflight icing. I am not aware of any icing-induced accidents or incidents that involve a properly functioning TKS system, There have been some events that involve a clogged system.

The same cannot be said of boots. Westhawk makes excellent points regarding operation and maintenance. However, a boot system will typically require several cycles to optimally clear the ice off the wing and keep it that way. Even when operating correctly, a boot system will likely leave some residual ice on the wing and there will always be inter cycle ice. These can be critical, and there is no such thing with a properly operating TKS system.

That said, there is the problem of fluid supply and proper maintenance with TKS.

In the end, a hot wing trumps all, but you will find that some manufacturers recommend operating the hot wing in a deice, as opposed to anti-ice, mode. I don't care for that...it leaves open the question of detection and inter-cycle ice... but when you dial back the available thermal energy, a hot wing runs wet instead of fully evaporative, and this generates runback ice. There have been some problems with that occurring in front of control surfaces. Using it as a deicer is supposed to improve that problem.