What was found
LEFT PACK FLOW CONTROL VALVE CLOSED POSITION SWITCH FAILED. FMC RECEIVES "OPEN" DISCRETE FROM TARGET CALCULATIONS. GROUNDED - YES. REMOVED AND REPLACED LEFT PACK FLOW CONTROL VALVE REF AMM 21-51-01, LEAK AND OPS CK'S GOOD.
- Difficulty date
- March 14, 2021
- Submitted
- March 16, 2021
- Operation
- Air carrier
- Aircraft
- N474AS
- Make and model
- Boeing 737990ER
- Aircraft serial
- 40715
- Aircraft time
- 21,478 hours, 6,834 cycles
- System (JASC)
- 2150 · Cabin Cooling System
- Part
- Control Valve
- Part number
- 3966081
- Part serial
- 3253
- Condition
- Failed
- Location
- Lt A/C Pack
- Part time
- 44,731 hours, 13,626 cycles
- Stage of operation
- NR
- How discovered
- 9
- Nature of condition
- O
- Precautionary procedure
- O
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.