49 C.F.R. § 229.55
Piston travel.
Cite as 49 C.F.R. § 229.55 (2026)
(a) Brake cylinder piston travel shall be sufficient to provide brake shoe clearance when the brakes are released.
(b) When the brakes are applied on a standing locomotive, the brake cylinder piston travel may not exceed 1
1/2
inches less than the total possible piston travel. The total possible piston travel for each locomotive shall be entered on Form FRA F 6180-49A.
(c) The minimum brake cylinder pressure shall be 30 pounds per square inch.