How safe is flying? Numerous studies on that question have been published in the months since the pandemic brought travel to a halt in March. Many of them suggest that the risk of contracting coronavirus while flying is very low.
The air quality on a commercial airliner is actually quite high, with the air volume in the cabin being completely refreshed every two to four minutes. Air flows into the cabin vertically — it enters from overhead vents and is sent downward in a circular motion, exiting at floor level. Once air leaves the cabin, about half is dumped outside, and the rest is sent through HEPA (high-efficiency particulate air) filters, similar to those used in hospitals, before being mixed with fresh outside air and entering the cabin again.
Of course, passengers and crewmembers moving up and down the aisles can disrupt this airflow, altering the path of any airborne particles. And while the HEPA filters used in commercial aviation can filter out 99.97% of virus-sized particles, they can’t capture every respiratory droplet or viral aerosol before someone else inhales it.
Your flight will be even safer if your airline requires all passengers and crewmembers to wear face coverings, which are designed to contain respiratory droplets before they can be expelled into the air. There’s real-world evidence that masks on planes can make a difference. True social distancing on a plane is impossible, but, as you note, some airlines are currently leaving middle seats unsold, creating a bit more space between passengers.
However, as many have pointed out, leaving middle seats empty is not a viable, long-term business model for an industry with razor-thin profit margins. But some airlines that have resumed selling middle seats have also committed to informing travelers when their flights are reaching capacity, allowing them to rebook on less crowded flights without penalty. Airline policies are constantly changing, so be sure to double-check your airline’s current stance before buying a ticket.