At the end of the pilot episode, just before Sarah, John and Cameron travel to the future, Sarah blasts Cromartie and you can see his head fly off. In this episode, Cameron reveals that Cromartie has traveled to the future along with them by pointing out his bare endoskeleton head in the background of the video that was taken of them just after they arrive in the future. It is supposed to be impossible for anything non-biological to time travel, so why is it that Cromartie's head made it through even though it was missing the surrounding living tissue?
[Cromartie's head is launched into the time vortex when still (mostly) covered by flesh. This, combined with its motion (as opposed to the standing position of the other three) may have affected how his head was treated by the device. Also, this time travel device in the vault is not the same as the one in the future, but is built by soldiers sent back to the 1960s to construct it. As such, it is possible a slight, unintended variation in materials, preparation or construction can have allowed for this to occur. Essentially, there are many differences between this event and those shown in the three films, any one of which could account for what happens.]
Corrected by John W Rosa
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