# SDR CALA2023112703474

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 24, 2023
- Submitted: November 27, 2023
- Operation: Air carrier
- Aircraft: [N16709](https://openairdocs.org/aircraft/N16709), registered now
- Make and model: Boeing 737724
- Aircraft serial: 28779
- Aircraft time: 79,241 hours, 28,480 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Indicator
- Part number: AW2835AB06
- Part serial: 9711559
- Condition: Inoperative
- Location: Cabin Pressure
- Part time: 79,212 hours, 28,471 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2023112703474

## Discrepancy

AT 10000 CABIN ALT WAS -1000FT. CABIN RATE OF CLIMB APPEARED NORMAL AT 28000 DIFFPRES WAS8 VERIFIED QUICK DISCONNECT PROPERLY INSTALLED. ADDING PIC T/S PER FIM 21-33 TASK 803. REMOVED AND REPLACED CABIN ALT AND DIFFERENTIAL PRESSURE INDICATOR, REF AMM 21-33-02-400-801. IDT REQUIRED FOR QUICK DISCONNECT. PARTS USED: 29-3111-9-0001,QTY :1 ROTABLE PARTS CHANGE WAS INDICATED - TT # 1555755 SN OFF 1559 PERFORMED LOW LEVEL STATIC LEAK CHECK REF AMM 34-11-00-790-808 LEAK CHECK PASSED REPLACED #2 CABIN PRESSURE CONTROLLER PRE CAUTIONARY. PER AMM 21-31-01-000-801 AND AMM 21-31-01-400-801. OPS CK NORMAL. PARTS USED: 29-2131-9-0003,QTY :1 ROTABLE PARTS CHANGE WAS INDICATED - TT # 1521210 SN OFF 1916 INDICATOR, CABI OFF 29-3111-9-0001 1559 ON 0000 INDICATOR, CABI OFF 29-3111-9-0001 1559 ON 29-3111-9-0001 8678 IPC REFERENCE # 21-31-01-400-801 CONTROLLER, CAB OFF 29-2131-9-0003 1191 ON 0000 CONTROLLER, CAB OFF 29-2131-9-0003 1191 ON 29-2131-9-0003 1905 PERFORMED CABIN PRESSURE LEAK CHECK, TO VERIFIY OPERATION OF CABIN PRESSURE INDICATOR, REF AMM 05-51-91. CABIN PRESSURE INDICATOR OPERATES NORMALLY.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.