The boots perish and need repair or replacement, and they are a bit of a hassle. Unless - like quite a lot of pilots - you don't bother, but then you (AIUI) can't get the Annual signed off.
They strike me as less hassle than TKS fluid but I guess like everything on a plane, they can break. Need something for my vacuum pump to do...
Most of the twins I have flown have had boots and they are pretty effective.
The jet had TKS on the flying surfaces and bleed air on the engine nacelles. There was always the worry about running out of TKS, so we tried to use it sparingly (it was on a timer) but in use it was far more effective than boots.
One claim made for TKS is that you don't get the clear leading edges with a load of ice forming just behind them, because the TKS liquid runs down the wing.
Another one is that you don't get "bridging" which can occur with boots, whereby a "bridge" of ice forms over the boot, and the boot cannot inflate enough to crack it. Some owners have said this is impossible while others have said they have seen it. Can anyone flying with boots confirm?
The fluid certainly can be messy. I have a TKS decied prop and while handling the stuff in 2 litre bottles and pouring it in with a funnel is easy enough, if you spill some it makes a right mess because it's a thick liquid which doesn't dry like e.g. avgas does.
Also I cannot see any way to get a refill enroute on a long trip across Europe. Same as oxygen really...
Why are there not more light aircraft with boots? Seems to me the simplest, cheapest and it works! it doesn't use expensive TKS fluid, doesn't have any issues with run-back and doesn't need an expensive plumbing job like a bleed air system?
I am not sure it is cheaper to have boots, the TKS system has simple power requirements, and only needs a small electrical supply for the pump. I would say it is a fairly serious plumbing job to have boots. On the Citation tail it uses 23psi service air to inflate the boots, and vacuum to hold them down. These have to come from somewhere.
Boots use a lot less power than bleed air heating for anti ice, but are regarded as less effective on the king air I occasionally fly. Perhaps on new designs like the Phenom they are better.
With the bleed air anti ice it never seems to be an issue
Boot replacement should not be underestimated. It seems that boots typically need replacing every 3-5 years, and it costs thousands of dollars per boot.
Another one is that you don't get "bridging" which can occur with boots, whereby a "bridge" of ice forms over the boot, and the boot cannot inflate enough to crack it. Some owners have said this is impossible while others have said they have seen it. Can anyone flying with boots confirm?
Oh, they definitely exist.
But they can be much more extensive. To be honest, when they are big you generally have other things on your mind than photographing them.
Boot replacement should not be underestimated. It seems that boots typically need replacing every 3-5 years, and it costs thousands of dollars per boot.
I don't know what to say. I have owned my aircraft since July 1995, when the boots were already patched, so clearly far from new, and have put about 2,500 hours on the aircraft since then, and none of the boots have needed replacement. I fear that someone has tugged your todger.
Boot replacement should not be underestimated. It seems that boots typically need replacing every 3-5 years, and it costs thousands of dollars per boot.
Not all boots. I have co-owned a Cessna 421 during the 1990ies for almost ten years and we sold it on with the same boots be bought it with! A few patches more, maybe. And never had the least problems with the boots, other than with the heated props and windshield that were a constant source of trouble. The aeroplane I fly now (luckily) has bleed-air de-ice for everything but the horizontal stabiliser. It must be ten years old now and the boots on the stabiliser don't have a single patch yet. I prefer boots over any other method apart bleed-air of course.
It is B F Goodrich that say the boots last 3 years or more. Clearly a lot more in many cases. I think it has a lot to do with how often they are used, and the amount of ozone and UV exposure they get, and also if the boots get any treatment to keep them pliable.
Clearly Goodrich would be more than happy if people changed them fairly often; the King Air 90 I occasionally fly has original boots, but we have had new boots on a previous aircraft. That was due to cracking/crazing, and I saw it with my own eyes, it was obvious when they were inflated.
Maybe the life on airline operations is shorter simply due to more use, and that's why Goodrich say that, I don't know really.
I am looking to buy a decent IFR capable SEP and I am interested in finding out more about the operational challenges of operating light aircraft IFR in Europe...especially with respect to airframe icing (as well as CB avoidance)....
It seems to me that there are a great many aircraft which have no more than a heated prop....probably because there are very few options available to single-engined aircraft for de-icing in terms of pneumatic boots or TKS....I assume those without full de-icing do not fly when icing is forecast (at or below the MEA)...or is there a more pragmatic approach?
And what is the likelihood of electic thermal (Thermawing) type STCs coming to the market?
AQ
There are a few with TKS, but SEP without anti-ice means you just can't go if there's a chance of icing.
Peter's your man on this subject, and I expect he cancels very few trips. I also suspect the reason he cancels few trips is because good flight planning means they aren't even considered if icing is likely.
