Abstract: A telescopic ladder includes a proximal end adapted to be fixed on a support, the ladder including between the proximal end and a distal end a plurality of sections displaceable relative to each other for deploying the ladder, the section arranged at the level of the proximal end of the ladder being made of material having a density greater than the density of the material of which at least one other section of the ladder is made.

Abstract: High-rise aerial apparatus mounted on a vehicle in which off-level correction is required comprises an elongate member particularly an extendable ladder or an optionally telescopic boom extending principally along one axis and able to be equipped with an aerial cage, platform or any type of similar supporting structure. The elongate member is mounted on a base, with an intermediate part interposed between the elongate member and the base, the elongate member being mounted on the intermediate part that pivots about a second axis for off-level correction of the elongate member, the intermediate part being pivotally mounted on the base via a third axis providing for elevation of a free end of the elongate member with respect to the base. Two rams for elevating and lowering the elongate member are pivotally mounted on the base and are each controlled by a controller, and can simultaneously apply off-level correction while elevating the elongate member through suitable control of the rams.