Service difficulty report · Control Valve · Cndair CL600*

Difficulty date
October 23, 2021
Submitted
October 26, 2021
Operation
Air carrier
Aircraft
N780QS
Make and model
Cndair CL600*
Aircraft serial
20568
Aircraft time
6,321 hours, 3,549 cycles
Part
Control Valve
Part number
398531
Part serial
1219
Condition
Defective
Location
Zone 700
Stage of operation
LD
How discovered
L
Nature of condition
O
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

OUTBD BRAKES FAIL AMBER CAS: UPON LOWERING LANDING GEAR, AMBER L OUTBD BRAKES FAIL CAS ILLUMINATED. AFTER A NO APU SHUTDOWN STARTED APU AND AFTER HYDRAULICS WERE TURNED BACK ON, AMBER OUTBD BRAKES FAIL ILLUMINATED. ADVANCED DIAGNOSTICS CODE ID#=B3-006383 // SIGNOFF // DOWNLOADED MDC AND SENT TO MCC / BOMBARDIER PER THEIR REQUEST PERFORMED THE RESET OF BRAKES: TEST PASSED, RAN THE BRAKE TEST WITH RESIDUAL PRESSURE FROM RUNNING PUMPS AND MONITORED ON MDC AND FOUND LH OUTBOARD TO SHOW 61PSI AND ALL OTHER PRESSURE SWITCHES INCREASED WITH BRAKE FORCE (WHICH CREATED A BRAKE F ALL CAS). PERFORMED OUTBOARD BCV RESISTANCE CHECKS: TEST PASSED. TURNED ON BOTH HYDRAULICS PUMPS AND PRESSED BRAKES AND MONITORED PRESSURE, BRAKES SHOWED ALL ABOVE 1000PSI EXCEPT LH OUTBOARD SHOWING 105PSL DISCONNECTED CONNECTOR TO BCV AND INSPECTED FOR CORROSION/ LOOSE CONNECTOR/ BENT BINS: NOTHING FOUND, RECONNECTED AND PERFORMED TEST AS MENTIONED ABOVE AND SAME RESULTS LH OUTBOARD BRAKE FAIL AND PRESSURE NOT INCREASING ON MDC. SMART FIX IS INDICATING A FAULTY BRAKE CONTROL VAL VE. PLACED BRAKE CONTROL VALVE ON ORDER (BAK). R&R OUTBOARD BRAKE CONTROL VAL VE W/ OVERHAULED UNIT !AW CL350 AMM 32-43-13. PERFORMED BRAKE BLEED PROCEDURE AND OPS/LEAK CHECK SUCCESSFUL. MONITORED PRESSURE ON MDC AND NOW ALL BRAKES READ 2800PSI WITH BOTH ELECTRIC PUMPS RUNNING. NO CAS FOR OUTBOARD BRAKE F ALL, BRAKES OPS CHECK GOOD.