De-ice boots

[Mason]

Aircraft: C402B

I was flying a 402 today and noticed that the de-ice boots "partially" inflate at rotation and then deflate on the landing rollout. I couldn't get them to completely deflate in the air. I could cycle the boots in flight but they would never completely deflate.

Does anyone have any suggestions as to what this could be. Let me know if you need any futher information.

 

[dbert]

I don’t know jack about a 402, but it sounds like the system that creates or controls the vacuum to suck the boots down is not functioning correctly.

 

[a&p cfiguy]

Its the low pressure created by the wing that's in effect pullinging outward on the deice boots. Probably not enough suction, possibly because of a leak in the boots somewhere. Very common in the 402s I've flown. A difficult problem to fix because it'll only happen in flight. A lot of mechanics blow it off, but it's a very serious issue. When the boots are partially inflated, they'll pick up more ice, and may not be able to get rid of it, or ice bridging may occur. Not a good situation.

 

[dhc8fo]

Its the low pressure created by the wing that's in effect pullinging outward on the deice boots. Probably not enough suction, possibly because of a leak in the boots somewhere. Very common in the 402s I've flown. A difficult problem to fix because it'll only happen in flight. A lot of mechanics blow it off, but it's a very serious issue. When the boots are partially inflated, they'll pick up more ice, and may not be able to get rid of it, or ice bridging may occur. Not a good situation.

Tail stalled a 340/421 sim at FSI last year under this scenario and it was just awful. Glad to never do it in real life.

 

[saab fixr]

sounds like a lot of holes in the boots need fixed and most places dont want to put patches all over them because if they have to many it will have to be replaced Most likely its a money issue to expensive Imagine that? just my 2 cents