TKS Prop de-icing system

[Speedbird744]

Anyone tell me how useful this piece of kit is if the PROP is the only heated element on the aircraft?
Does it have any impact on the wing surfaces?

Finally would you as a pilot feel confident entering light icing using this as an anti-ice as well as de-icing equipment? Assuming the prop is only heated and there are no boots.

[IO540]

TKS uses de-icing fluid, not heating.

I have a TKS prop. It is totally effective on the prop, and stray fluid gets sprayed all over the windscreen and also over about 2ft wide section of each wing, close to the fuselage.

It cannot be used for sustained flight in actual icing conditions because eventually the wings, elevator and airframe will ice up, and anyway the fluid won't last for ever.

[dirkdj]

The main reason for prop deicing (heat or chemical) is to prevent prop vibration if one chunk of ice comes off on one blade. Apart from the vibration issue, deicing the prop offers practically no performance benefit in icing.

TKS prop deicing offers a small side benefit as IO540 explained, but it would be a waste of time weight and money not to go to the full TKS system since you would already need the pump, reservoir, timer etc anyway.

On a certification test of the T210, rate of climb with no ice was 900fpm; with boots and prop deice 700fpm; with boots only 500 fpm, with prop only 200fpm; with no protection 100fpm at sea level. With TKS the airplane would have been practically ice-free.

Even in a strong, turbocharged, known-icing certified twin pneumatic boots won't do the job as I experienced on a dark night at 4000ft over the North Sea.

[IO540]

dirkj

Apart from the vibration issue, deicing the prop offers practically no performance benefit in icing.

Where is this stated? It cannot be right; an iced up prop won't work because it is an aerofoil just like a wing.

Also the pump for prop-only TKS is tiny, the fluid container is tiny and there is no timer, just a low/high/off switch. The W&B penalty is negligible.

The W&B for the full TKS is significant but those that encounter icing would consider it a fair price to pay - any other method e.g. boots and an electric prop is also heavy enough, and boots are frequently getting punctures. I'd go for it.

[dirkdj]

IO540,

this data is from the T210 known icing certification. I have electric prop deicing on my A36 and this matches my experience. The only part that will ice up on a prop is the inner third and that doesn't do any useful work except keep the outer prop blades where they belong.

I didn't know there was a prop only TKS system.

Icex II from Goodrich is a spray-on silicone liquid good for 25 hours and it is a good alternative for non-deiced props, A small can is over 100€ but well worth it.