I found something really cool:
1- Attach a few sliders in a line on the source blocks.
2- Connect the source block and the last slider with a contractable spring.
3- Set its strength to a negative value.
4- Pin the last slider and the source block, make sure they have different unpinning keys.
5- Start the simulation.
6- Unpin the last slider.
try using some "aerodynamic propellers" small or large on the back (raised) and the front (lowered) of your vehicle.
This works because the wing blade thingys are forcing the vehicle down due to the air passing over it which pushes it down. (I'm no plane engineer)