14 CFR 23.485 - Side load conditions.
(a) For the side load condition, the airplane is assumed to be in a level attitude with only the main wheels contacting the ground and with the shock absorbers and tires in their static positions.
(b) The limit vertical load factor must be 1.33, with the vertical ground reaction divided equally between the main wheels.
(c) The limit side inertia factor must be 0.83, with the side ground reaction divided between the main wheels so that -
(1) 0.5 (W) is acting inboard on one side; and
(2) 0.33 (W) is acting outboard on the other side.
(d) The side loads prescribed in paragraph (c) of this section are assumed to be applied at the ground contact point and the drag loads may be assumed to be zero.