You need to get 500 and 1,000 points for landing a single ship to unlock these achievements. Each ship has a base score, which is multiplied by the current multiplier when the ship lands, given the total points for landing that ship (the point value flashes when the ship lands). 1,000 points is easy to get and will come without even trying. This can be obtained in any game mode, but it easier in Infinity mode where you can earn a limitless color multiplier (as opposed to Odyssey where the multiplier is capped at x5). Also, to improve your odds, equip the Critical Score Robot, which will randomly give you extra points on ships you land.
NOTE: You are guaranteed to get 1,000 points for a ship when going for the x50 multiplier required for the "Malt Runway 2" achievement, so you should probably just follow the description for that achievement.