this accolade - as best i can understand it - seems to require 2 ppl teaming the air master phase of an Horizon arcade Air sequence… Solo i max out at 10 but if we tag in turns we can each get the 750 pnts!?
That accolade is a bit annoying as you discovered… If you try to do it alone, you have a max of 10 air skills to get, so you don’t meet the 20 required.
If you have 1 or more people with you, the bar expands to 20 or 30 I believe, however - you still need to manage 20 in one shot, by yourself.
So, you’ll need to either organize with a friend to do the event, but they sit back and allow you to do the air skills by yourself…
or
You’ll need to be with someone that is new and slow and doesn’t understand what to do, so if you are faster and fast travel right away, you can potentially get to the zone and rip through 20 skills before they arrive and do any.
I got ‘air miles’ completed by doing the second thing, found a new player and he had no idea what to do,… got my 20 skills and he showed up after,…
good luck, hope this helps
If you need to team up i will gladly help, I already got this one but don’t mind helping at all, I’m in UK and will be on at 13:00 GMT tomorrow Xbox gamertag same as forum user name 
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