A GoPro photo can provide many details.
This interesting photo taken by MigFlug videographer Artur Sarkisyan shows the upper end of the Edge of Space flight profile (click below to enlarge).
Here’s the meaning of the points on the image:
- acceleration from a height of 12,000m at a speed of Mach 1.8 (at sea level 2,222km/h or 1,380 mph – at this altitude 1,950 km/h or 1,210 mph)
- Set of the height
- height = 18,000 m
- reduction of height, return from the stratosphere