pjank42
commented
9 years ago was just glad I found something that wasn't hard to do, and it all goes off certification date, so it can be done once per model and that's it. It could also be used as a restriction, as in Australia no longer allows stage 2 aircraft and just recently banned all Boeing 727's, even stage 3 compliant ones. I would love to see this become a more realistic restriction in the game. Maybe it could be set as a "stage" restriction then maybe specific model restrictions after that.
http://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/22942 The important numbers, if you got to the pdf (I was planning on sending it via Skype, but for some reason it simply would not send) is the "Stage" it is a level of sound the airplane is allowed to emit. For instance an old B722 is a stage 2, which is allowed to be very loud, while a more modern B738 is a stage 3, much quieter, and a B789 is stage 4, very quiet.