Does anyone know anything about a step added onto the side of an Ontario based AStar so linemen can get out onto the top of a tower structure? Is it still used? Is it STC'd? Is it available?
The step you are referring to might be the Helinas system used on the TwinStar. It is a work platform for the maintenance of items such as marker balls and insulators. I'll try to find a decent picture of that. It was not intended for disembarking in flight as, I believe, it has a set of counterweights on the opposite side of the fuselage.
Just a few years ago we were only allowed to use the 206 for tower landings. It had to be equipped as per some BC Hydro guidelines... Remove bearpaws, remove starboard doors, remove skid bolts for the gound handling wheels, remove range extender, and attach the STC'd handle. Pretty much the configuration shown below.
Ontario likely has a different set of rules, but the Astar is not the best choice as it can get into a ground resonance situation on the bridgetop. It happened to a co-worker on my base and scared the heck out of him.
The door was left on this aircraft as it was only a training flight.
I believe Ontario Hydro has designed their own system called an air stair for use on their A-stars. I don't believe they have an STC as of yet, but could be wrong. It is used for embarking and disembarking on tower structures.