(a) Wheel climb. (1) Suspension systems shall be designed to reasonably prevent wheel climb, wheel unloading, rail rollover, rail shift, and a vehicle from overturning to ensure safe, stable performance and ride quality. These requirements shall be met—

(i) In all operating environments, and under all track conditions and loading conditions as determined by the railroad; and

(ii) At all track speeds and over all track qualities consistent with the requirements in subpart C of this part, up to the maximum trainset speed and maximum cant deficiency of the equipment in accordance with § 299.609(g).

(2) All passenger equipment shall meet the safety performance standards for suspension systems contained in § 299.609(h). In particular—

(i) Vehicle/track system qualification. All trainsets shall demonstrate safe operation during vehicle/track system qualification in accordance with § 299.609 and is subject to the requirements of § 299.315.

(ii) Revenue service operation. All passenger equipment in service is subject to the requirements of § 299.315.

(b) Lateral accelerations. The trainsets shall not operate under conditions that result in a steady-state lateral acceleration greater than 0.15g, as measured parallel to the car floor inside the passenger compartment.

(c) Journal bearing overheat sensors. Bearing overheat sensors shall be provided on all journal bearings on each trainset.