There's not much to say really. Normal prismatic mare, normal Ponyville morning. Normal flight, normal normalcy. Not much to say about 'normal' in Ponyville, as it doesn't tend to come around for more than the conceivable seven to eight seconds at a time.

In this case, the unexpected span of about five seconds happens.

Rainbow was practicing a trick, a little too close to the ground just as a branded van turns a corner. A series of events follows, and you really don't need me to further explain from here. Good luck.

(A personal attempt to try and include as many copyrightable things as possible in as close of a narrative turn as feasible.)

(Sister Story, much love to Estee)