Originally Posted by The Ancient Greek
...My only gripe is the cockpit noise levels, has this improved in the -400?
I wish I could say we did something magical to make the aircraft quieter, but we did not.
We do fit all new Series 400 aircraft with David Clark noise cancelling headsets (powered from the airframe) as standard equipment. They make a big difference. I just finished doing a ferry flight halfway around the world, and I felt a lot better getting out of the 400 at the end of the day than I used to feel when I got out of the 300.
Four blade props have been tried in the past - both Raisbeck and Field Aviation developed STCs for them - but they change the low speed handing characteristics of the aircraft, and that is not a good trade-off.
At the moment, we are looking at possible ways of reducing flight compartment noise passively by using some advanced foam material between the outer skin of the aircraft and the fabric interior. The problem with this strategy is that foam can trap moisture (condensation), and that will lead to corrosion. Foam also adds weight to the aircraft. Work continues, and if we come up with a solution that reduces noise without creating other problems, for sure we will implement it.
Michael