Bad Piggies Flight in the Night Level 4-29 can be three starred using a single contraption. The vehicle is two boxes wide. From bottom to top, the vehicle uses wooden wheels, wooden boxes with TNT, vertical springs, and finally metal boxes with our piggy and egg. Let the contraption drift to the bottom of the hill. When it angles the metal boxes leftward, blow the TNT. Fire in the hole!
If you have a different strategy for completing this level feel free to leave a comment below.