RedactedNarrative: On July 4, 2020 at approximately 5:30PM, V1 was boating northbound on Lake Francis Case. This is near Chamberlain, South Dakota. V1 was on plane for approximately 20-30 seconds tubing. V2 was stationary. O2 asked P2's if the coast was clear. P2's affirmed to O2 the coast was clear. V2 began to accelerate while tubing. V2 was accelerating for approximately 15-30 seconds before the collision. V2 collided with V1 on the front panel starboard side on first impact. The secondary impact was near the rear starboard bottom stern.