> With respect to the down draft, I sometimes have a problem when > cruising > in high winds when we pass under a bridge and the stove blows out, but > I > only have a short single walled chimney on and the stove is running at > tick over > > -- > Brian Ancient Order of Sewer Ants > I have that problem too, as Brian recalls only too well!! It occurs roughly from when the wind gets strong enough to interfere a bit with the steering - more serious when going upwind than downwind, probably because the pigeon-box and funnel offer some protection downwind (because the downdraft is a combination of the horizontal wind blowing through the aperture and the wind which has struck the face of the bridge spilling down, it's most severe a couple of feet under the arch).
Sean
