ATA 32

Brake Fuse
A fuse is installed between the forward and rear brake line at the main gear. Why is the fuse in the system? If this fuse were installed backwards, what would be the effect on the normal braking system? On the emergency braking system? Answer: The fuse is in the system to prevent the loss of braking should a rear brake line fracture. If a forward line were to fail, the emergency brake system would still function through the brake shuttle valve. If the aft line were to fail, the fuse would stop the flow of fluid overboard and allow the forward brake housing to continue to work. If the fuse were to be installed backwards, the system would work normally unless you had a rear line failure. If the rear line broke, all braking fluid to that gear would be lost overboard.