# SDR CALA2026052016392

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 19, 2026
- Submitted: May 20, 2026
- Operation: Air carrier
- Aircraft: [N26960](https://openairdocs.org/aircraft/N26960), registered now
- Make and model: Boeing 787-9
- Registry model: [Boeing 787-9](https://openairdocs.org/model/boeing-787-9) (OpenAirDocs)
- Aircraft serial: 36408
- Aircraft time: 49,655 hours, 4,732 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Acm
- Part number: 7110121H01
- Part serial: 7883
- Condition: Faulted
- Location: Right
- Part time: 49,654 hours, 4,732 cycles
- Stage of operation: TX
- How discovered: O
- Nature of condition: B
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026052016392

## Discrepancy

AT GATE RETURN FLIGHT CREW REPORTED BURNING ODOR SMELL IN CABIN. FOUND 3 STATUS MESSAGES REF LP 8941702, 8941648 AND 8941641. RT PACK WOULD NOT TURN ON. PRESSED PACK RESET SWITCH WHICH CLEARED THE MESSAGES THEN CYCLED PACK SWITCH ON. WITHIN 1 MIN OF PACK RUNNING HEAVY ODOR SULFUR ODOR FILLED CABIN & FLT DECK THEN RT PACK SWITCHED CYCLED OFF & ODOR DISSIPATED.  CYCLED LT PACK SWITCH ON FOR AT LEAST 10 MINS UNTIL ACFT DEBOARDED & NO FURTHER ODOR NOTED. UPDATING FAULT CODES  21-65223,21-65173, REF FIM DMC-B787-A-21-50-F2-71A-421A-A PERFORMED RT ACM BREAKAWAY TORQUE FUNCTIONAL TEST IAW AMM DMC-B787-A-21-52-02-00A-340A-A. BREAKAWAY TORQUE OUT OF RANGE & FOUND EVIDENCE OF ACM OUTLET TURBINE SCRAPING HOUSING. LP 8944726 CREATED FOR REPLCEMENT OF RH ACM. REF LP 8944726 REPLACED RH ACM. CABIN AIR CONDITIONING/TEMP CONTROL SYSTEM RIGHT PACK AIR OFF AND RIGHT PACK AIR ON TESTS PASSED. OPRATED RT PACK FOR 1 HR, NO UNUSUAL ODOR AND NO MX MESSAGES. BOTH LT & RT PACKS OPERATE NORMALLY. REMOVED RT ACM IAW AMM DMC-B787-A-21-52-02-02A-520A-A.

---
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.