Farmer Joe and Jeff are chugging along up a hill with a truck full of chickens. As the hill gets steeper the trucks goes slower and slower until it...

Farmer Joe and Jeff are chugging along up a hill with a truck full of chickens. As the hill gets steeper the trucks goes slower and slower until it can no longer climb the hill. They decide that to get up over this hill, one of them should scare the chickens so that they fly up a bit (chickens don't fly high, only a foot or 2), take some weight off the truck, and then drive up a little until they land again. They will repeat this until they've gone over the hill. Can this work? Why or why not?