Unfortunately, this challenge keeps track of the number of Ultimate Air skills you've performed and not the points you have amassed like the description states. So you cannot make use of your Horizon Edition cars to speed this up.
You'll need a total of 84 Ultimate Air skills to knock this one out. I recommend paying a visit to the Outback, there are an abundance of dunes that are perfect for Ultimate Air skills.
One such spot is immediately south of the airport, beneath the makeshift roads that connect to the southern end of the airport (see the image below). There are roughly seven or so jumps that run from east to west that provide enough lift to award an Ultimate Air skill. Simply go back and forth, accumulating as many as you can.
Banking the skill chain does not seem to matter, my achievement progress moved as I was running the course. If someone else could confirm, that would be great! Either way, I recommend a heavier car, so you are less prone to flipping (which, in turn, takes less time by not having to deal with rewinds and resets).