This page from The New York Times examines the risk of contracting Covid-19 on a flight. While dangerous variants have increased concerns, the air in planes is a mixture of fresh and recirculated air, refreshed every 2-3 minutes, which helps decrease the incidence of superspreader events in flights. However, risks can increase if passengers remove masks temporarily, and although the plane's design contains air circulation to nearby rows, complete safety can't be guaranteed.
Impressive visualization of airplane ventilation systems…