Document ID: chunk:federal_register_of_legislation:F2023C00958:reg:7:p13
Version: federal_register_of_legislation:F2023C00958
Segment Type: reg
Provision Reference: reg 7 (pt 13/16)
Character Range: 46397–49395

plane.
21.5.6.2.3.              The height of the CoM is given by the formula:

h = [(W - L) / tan θ – (We - Le) / sin θ] + r

         Where:

         Le is defined by the formula in 3.2.2 above;

         θ is defined by the formula:

θ = arctan (Hfe / We)

         Hfe is the height by which the front wheel is elevated;

         r is the rolling radius of the tyre fitted to the rear wheel;

         W is the wheelbase of the vehicle prior to elevation; and

              L is the longitudinal location of the CoM prior to elevation (determined in clause 21.5.3.1).
21.5.6.3.                    Height Location for LEM2, LEP2 and LEG2 Category Vehicles (See Figures 3 and 7):
21.5.6.3.1.              The height of the CoM shall be determined as follows:
21.5.6.3.2.              With the suspension blocked to prevent movement and the vehicle in the 'Maximum Loaded Test Mass' condition, use blocks to elevate the rear to not less than 600 mm (Hre), and determine the longitudinal location of the CoM in the elevated state (Le), from the centre line of the front 'Axle', using the formula:

Le = WeRe / (Fe + Re)

         Where:

         We is the wheelbase in the horizontal plane;

             Re is the rear 'Axle Load' on the tyre(s) with the elevated vehicle in the 'Test Mass' condition; and

              Fe is the front 'Axle Load' on the tyre(s) with the elevated vehicle in the 'Test Mass' condition.

21.5.6.3.3.              The height of the CoM is given by the formula:

h = [(L / tan θ) - (Le /sin θ)] + r

         Where:

         Le is defined by the formula above;

         θ is defined by the formula:

θ = arctan (Hre / We)

         Hre is the height by which the rear wheel is elevated;

         r is the rolling radius of the tyre fitted to the front wheel; and

              L is the longitudinal location of the CoM prior to elevation (determined in clause 21.5.3.1).
22.                                      RETRACTABLE AXLE
22.1.                                Operating Safety
22.1.1.                          A 'Control' may be provided to manually move the 'Retractable Axle' up or down.
22.1.2.                          Where a manual 'Control' for lowering of the 'Retractable Axle' is fitted;
22.1.2.1.                    the 'Control' or the enclosure in which it is contained must be lockable, and
22.1.2.2.                    the 'Control' must be located within 2.5 metres of the centre-line of the 'Axle Group' which contains the 'Retractable Axle'; and
22.1.2.3.                    the 'Control' must not be accessible from within the cab of the vehicle.
22.1.3.                          the 'Axle(s)' must not be able to be moved from the 'Fully-down' position while the load on the 'Axle Group' is greater than the 'Prescribed Transition Mass'.
22.2.                                Tampering and Malfunction
22.2.1.                          Any system malfunction, attempted tampering or loss of power (e.g. trailer uncoupling) must result