I have seen a significant number of videos and prototypes for hatch mechanisms that use a pneumatic cylinder to deploy the hatch from a Velcro backed plate. Most of those videos have used the bare cylinder rods or something smaller. Is this legal based on R8?
It does not say that anything less than 1 in sq is illegal it just says it will invite detailed inspection.
I am recommending my team to put some end caps that are >1 in square and designing our recess holes large enough to accommodate it since it will be easy to do at this point, but this could be a more challenging fix for someone that shows up at competition if it is deemed illegal.