Rainbow Dash attempts a new stunt to impress the wonderbolts, using a giant ramp and a sled, but when something goes wrong, she and Pinkie Pie crash through the ice of a nearby lake. After they both get to dry land, it becomes obvious that Pinkie needs immediate medical attention. Fluttershy take it upon herself to get Pinkie to the hospital.

It's listed as incomplete, as I want to write a short epilogue in a few days