simple question

[Taka]

The sentence:

The decision had been made to go ahead with the launch, in spite of a near-disaster on an earlier Challenger flight in 1983.

What does "on" mean there? I think it's a part of "on a flight", and is used to indicate the state or process of the flight, but I'm not confident on this one...

[Tdol]

It does, but it's a bit euphemistic considering what happened to the Challenger.

[Taka]

It does, but it's a bit euphemistic considering what happened to the Challenger.

Thank you, tdol.

(What word would you use insted of "on"? "During"?)

[Tdol]

They both are OK.