APE Helicopter Caisson Template Flies Again!
Reported From: APE Northeast (NJ)
APE, Erickson Air Crane, and Overland Contracting of Baltimore, MD are working together on Conectiv Power’s Red Lion to Dover Delaware 230kV transmission line. Due to the marshy site conditions, conventional cranes are not an option. All equipment must be flown in via Erickson’s helicopter.
First, large wooden mats are flown in. Then comes the APE Helicopter Caisson Template, which houses an APE 350 Power Unit. Next comes the APE 150T Vibro with a caisson beam and 2 clamps. The caissons measure 48″ in diameter by 37.5′ long and are 12-sided. The caisson is already clamped to the vibro using an auxilliary power unit in a yard close by, and is then rigged to the vibro as a precaution. As the chopper hovers overhead slowly lowering the pile into the template, the ground crew quickly connects the hydraulic hoses while trying not to get blown away by the huge gusts, and the pile is carefully vibrated in. As soon as the caisson is able to support its own weight and the vibro while staying plumb, the helicopter releases the vibro rigging. The caisson is then driven to elevation, while the air crane flies mats to the next site. The process is then reversed. The air crane later installs the remaining segments of the pole.
The experience of being on the ground while the air crane hovers above is remarkable. It is stressful, chaotic, and intense, but mostly exhilarating. Ultimately one finds him/herself eagerly awating the chopper’s return for the adrenaline rush from rotor wash.
