Anyone have any difficulties with the cabin pressure flapper valve in their IVP?
In our airplane, the valve vibrates very noisily as it seats during pressurization...I am used to it but new passengers think we are breaking up until I explain it to them.
We have tried putting a soft edge on it but seems not to make a difference......there seems to be a conflict between ram air coming forward from the tail and pressurization air flowing into the cabin from the turbos.
One hint is that as we pressurize, we feel quite a bit of ear pressure as it surges, but then settles down and the “clacking” noise disappears.
The Dukes rate controller is set at mid way.

Phil Sexton
VH LLW
Melbourne Australia