Pressurisation systems
Question from a work colleague. Well you know how it is when you are a weekend PA28 flyer and they think you know it all about B747 systems ....
When you pressurise a commercial aircraft, how do you make the transition ? If say the cabin altitude is determined to be 8,000 feet for the flight, do you go unpressurised up to that height and then just close the valves and maintain the pressure above there ? And the reverse on the way down ? Or is there some more complex way of handling things which starts off nearer the ground and adjusts things more gradually ? Can you end up landing with some pressure still inside which has to be dispersed on taxi ?