As the spacecraft rise from the ground, constantly accelerating, wouldn't even something as small as a soda can have enough of an impact to alter the course, however minimally it might do so? With the very slightly altered trajectory, isn't it possible to throw the entire flight path out of synchronization? There is also the possibility of one hitting a hot air balloon at high altitude or even some mountain climber attempting to scale Mount Everest. It still seems to be an unnecessary venture.