As a kid (in the early 70s) I remember the air hostesses walking down the isles with a spray can. They don’t do that any more, but I wonder if or why they don’t add lower concentrations of the aerosol to the air conditioning at the end of the flight.
You could spend tens or hundreds of millions building an automatic system (certification for aircraft is not cheap or easy) or just hand the flight attendant a can of spray.
Sure, but I can imagine the more expensive airlines worrying that the ‘optics’ of spraying your passengers down aren’t great (to be clear - I’m not objecting and I’d rather they do it). I wasn’t suggesting they retrofit to existing aircraft of the period, but rather just build it in as they design the next generation airflow system. Or do you think it would still be way too expensive even then?
Adding systems to aircraft, whether retrofit or new design, is a horrifically complex and expensive thing.
What kind of disinfectant is used? How is it distributed? Does it do something bad at -80 degrees C? At +80 C? If it freezes, what happens? What if someone loads the wrong thing into the disinfectant bucket? Like fuel? Or oil? Where do we put the switch to isolate the cockpit from the disinfectant? Where does flipping that isolation switch go in the unknown-fume-event checklist?
What if it catches fire? It's not enough to say it can't catch fire, you must assume it will catch fire. The fire suppression system has to be aware of it. What if the fire suppression system erroneously thinks the disinfectant system is on fire? What if it was erroneously thought to be on fire, and then later _actually does catch fire_? How long can we fly with a flaming disinfectant system that someone in Terribadistan filled with kerosene?
You probably have more than one disinfectant module, probably attached to each pack. Is the plane "disinfected" if only one pack is operational? If your disinfectant module fails, does it bring the pack down with it? No? Now we have to certify the packs for both with-and-without disinfectant module operation.
Cockpit announcement: "The authorities here require us to have flight crew spray for mosquitos upon landing using aerosol cans before opening cabin doors. you will now see the attendants walk down the aisle spraying so we can unload you as soon as possible."
It would still be expensive for next gen too. Having to design an entire system that has never existed before that can operate under aerospace conditions is expensive as hell even before you get into certification. A sibling comment points out all of the design certification issues you need to think about
