# SDR ASAA2020012403905

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 20, 2020
- Submitted: January 25, 2020
- Operation: Air carrier
- Aircraft: [N557AS](https://openairdocs.org/aircraft/N557AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35176
- Aircraft time: 51,961 hours, 15,158 cycles
- System (JASC): [2310 · HF Communications System](https://openairdocs.org/jasc/2310)
- Part: Hf Comm
- Condition: Malfunctioned
- Location: Nr 1 & 2
- Stage of operation: CR
- 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/ASAA2020012403905

## Discrepancy

HF #1 AND HF #2 NO COMM, WE COULD HEAR THE SIDE TONE CHANGING FREQS. BUT WE COULD NOT MAKE CONTACT WITH SFO RADIO OR HEAR OTHER AIRCRAFT. GROUNDED - YES. DIVERSION TIME 53 MINUTES - ACCOMPLISHED B737-800 FIM 23-11 TASK 806 & AMM 23-11-00-710-801, CONTACTED SFO RADIO, BOTH #1 & #2 HF RADIO, OPS CK NML.

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