Agreed, my 737 fears were relieved by researching how many of them are in the air at any moment, how many millions of trips they fly each year, how old airframe

Agreed, my 737 fears were relieved by researching how many of them are in the air at any moment, how many millions of trips they fly each year, how old airframes can get before they get retired, etc. Even the "worse" models are feats of engineering.