The pilot of the CubCrafters CC-19-125 reported that, while attending a backcountry flying course, he had completed several off-airport landings with a flight instructor before returning to McCall Municipal Airport (KMYL) in Idaho.
During the landing roll to Runway 34, the left brake “flopped” under his foot when he applied the brakes. The airplane veered to the right. The pilot was unable to maintain control of the airplane and it traveled off the side of the runway and down an embankment, where the left wing and tail hit the down-sloping terrain. The pilot was then able to taxi the airplane back to the ramp.
Post-accident examination by an FAA inspector revealed that the left brake line near the caliper was separated and the left wing and elevator were substantially damaged.
The brake caliper and brake line components from the left main landing gear were sent to the National Transportation Safety Board Materials Laboratory in Washington, D.C., for examination.
The brake line 45° fitting at the lower side of the caliper was fractured.
Examination of the fracture surface revealed characteristics consistent with a ductile overstress fracture.
Additionally, a sliding contact mark was observed on the lower surface of the caliper aft of the fitting. The surface within the contact mark was smeared and exhibited a deformation pattern consistent with contacting an object moving forward relative to the brake caliper. An additional contact mark was also observed on the aft side of the fitting adjacent to the sliding contact mark on the caliper.
Probable Cause: A loss of directional control during the landing roll due to a fractured brake line fitting on the brake caliper.
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This June 2022 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
I landed “off airport” a few times in my C-150 and it’s always a threat. Once I landed on a little use dirt/grass runway and there were a few gofer holes….turn out they were these huge badger holes. I was lucky after hitting one that there was no damage….What do you do if you get stuck in the middle of nowhere?
Wonder if the other side is similarly upside down also? Could be the maintenance mechanic disassembled both sides simultaneously and didn’t remember which set of parts was which when he slapped them back on the airplane. If the owner did the job under a shade tree, then it’s his fault. If a shop did the work, that’s negligence and time for a New York lawyer to get money to fix the airplane. At a different airport could have resulted in injury and/or death. Who can you give blind trust to these days? Looks like choosing a repair shop for GA aircraft is just a crap shoot.
Regards/J
I looked at the CC maint. manual, and it shows a 90 degree elbow, and looks to be cad plated steel. The 45 degree fitting in the pics is a blue aluminum fitting…??
Also the Berenger brake installation shows the fitting on the top of the caliper and the bleeder at the bottom….This is more protected from FOD.
Maybe add a shield to protect the brake fitting and line from FOD, since the aircraft is designed for non-paved landing surfaces. ?
I know Beringer brakes are special; but I’ve never seen ANY single-caliper disc brake assembly on a light aircraft, where the caliper was mounted with bleed valve on the top and the brake line on the bottom.
It looks like this was mounted upside down, putting the line closer to “the threat”. Why would you do that?
My old Cessna has the brake caliper mounted behind the gear leg, and has the fitting at the top , with the bleeder valve at the bottom.
BTW, the Cessna bleed process is to pressure bleed from the caliper to the reservoir.
So a bleeder at the bottom of the caliper makes it easy to get the air out.!