I have a 160 PA-24-250 and the defrost vents are simple holes in the instrument panel cover with some scat hose connected. This blows a narrow jet of very hot air directly onto the windshield which has caused deformation and cracks to appear. I am planning on replacing the windshield next annual but also want to change the vents so this doesn't happen again.

The panel cover is quite flimsy and an alteration would be very simple thing. Has anyone done anything like this? I was thinking of fabricating something more like a slot with some vanes to spread the air over a larger surface area so that it might slow down and cool before reaching the plastic windshield but if there is something already out there...

William

William,
We used a ashby glare shield, now sold by Aircraft spruce I believe. I then riveted two of the cherokee style divererters over the defroster hole. This provides some diffusion, however it still puts out a lot of heat.
Hope this helps

Andrew
61 250

I was thinking of something like this...

Here is our ashy glare shield with Cherokee style diverters

Two more pics
One looking through the windshield showing the defroster
The other is the glarevshield installed
This on a 61 250

That looks a lot simpler. It's 1" scat hose I think. Just screw them right over the opening, I suppose.

William
The pic of the hole is looking through the windshield. The scat hoses are connected at that point underneath. The Ashly glare shield lays directly over everything. Heat is diffused by the Cherokee style vents.

Andrew