Gee... While we're "forgetting about" technical considerations, weather, and company manuals, and ONLY considering your "demand" for noise abatement, why not just use disposable airplanes without landing gear, and "forget about" injury to passengers and damage to airplanes and airports...
How long/far does it take for the gear to come down, airplane to decelerate to landing flap speed, extend the landing flaps, decelerate to final approach speed, and stabilize at that speed? Add that to the nominal 1000' or 3 NM from the airport for the stabilized approach minima, then add an appropriate safety factor (50% seems to be popular in commercial aviation).