According to this article, however the contact tracing of people who may have been exposed to identified positive airline passengers is poor in many countries.
It is hard to believe since most passengers were unmasked until recently.
"We are collecting data on the possibility of transmission onboard aircraft. With everything that is being done on aircraft, with respect to cleaning between flights, with respect to the air flow system, with the way the air flows on the aircraft, there is no evidence, there is not a case yet of somebody actually picking up the virus onboard the aircraft," he said.
There are plentiful reports of flight staff being infected with COVID.
Emirates airline, the United Arab Emirates flag carrier, has become the world's first airline to offer to cover customers' medical expenses and quarantine costs should they contract Covid-19 during their trip. https://www.cnn.com/travel/article/emirates-covid-19-expenses-cover/index.html
"Here’s how coronavirus spreads on a plane—and the safest place to sit"
"How Coronavirus Spread In One Restaurant Shows Why Air Travel Is Safer Than You Think"
Regardless of the scientific data for the air circulation inside the plane, don't forget the "walkway of death" when boarding or getting off the aircraft, where a steady flow of air is hitting you directly in the face, possibly carrying respiratory droplets from people who don't care about the others as much as you do:
I worked with many people who came down with the flu and missed a few days of work (in normal times) right after flying, I don't see how the coronavirus would be more forgiving. Take care.
One of the Hawaiian Airlines Covid cluster victims in the article died yesterday. He said on day 1 of the training session there was no sd or masks (except himself since he was the only one worried about Covid.) How dumb can people bein late June 2020? Well, day 2 was even worse. Afterwards HA put in some guidelines for future training sessions to protect people.
I would say that the flight isn’t that high risk but the destination could be. Hotspots like the USA (currently) are not good places to travel unless you have to.