The lift is hydraulic and I believe the primary safeties are mechanical, they latch into the "windows" in the ladders as the lift goes up. When I lower it, if I don't hit the air button to disengage the secondary air locks the lift settles on the primary's (that's where it is now). In order to lower it at this point it has to be raised off of the primary safeties, that's why I'm thinking it might be okay to not have the air on, but not sure.