Engineer
I didn’t say that the aircraft cannot meet the certification. What I said was that the aircraft was within 1dBA of the certification limit based on the cumulative totals for takeoff, lateral and approach noise levels.
For comparison, a B747-100 is 3 dBA quieter than a hushkitted 727-100.
My data comes from having to establish with the DGAC a list of aircraft that we were permitted to operate into CDG at night. Neither of the two above are permitted regardless of the stage-3 certification.
If you want to show that your aircraft is different, give me the certified noise levels from the AFM.
Cheers
mutt