Date: 201503
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Light: Night
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: System Monitor: Indicating and Warning
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Human-Machine Interface; Workload; Communication Breakdown; Confusion
Anomaly: Aircraft Equipment Problem Critical; Inflight Event / Encounter Other / Unknown
Detector: Person Flight Crew
When detected: In-flight
Result: General Maintenance Action
Contributing factors: Aircraft; Human Factors; Manuals
Primary problem: Aircraft

Narrative: In cruise mid-way through the flight; we received a SMOKE FWD CRG DET FAULT message. We completed the ECAM; completed the Cockpit Operating Manual (COM); and then looked for a COM reset. The reset in COM 3.224.15 says 'On Ground' only; so we did not perform it. As soon as I finished looking up the reset (within a minute or two of the first ECAM); we then received a SMOKE AFT CRG DET FAULT message in addition to the SMOKE FWD CRG DET FAULT message continuing to be displayed. The COM procedure was the same for both messages; and the reset was not applicable to either message.We both considered it unusual to receive one of these messages; and then the other a couple of minutes later. It seemed more likely that a Cabin Intercommunication Data System (CIDS) fault would cause both of these messages to be displayed simultaneously. We considered the situation to be additionally unusual because the Airbus Flight Warning Computer (FWC) software did not have a combined message for this situation (i.e. FWD + AFT); and therefore it seemed to be a situation that is considered not likely to occur.The COM 'condition' for each of these messages is 'Smoke detection fault.' The ECAM Status page displayed; under INOP SYS; 'FWD CRG DET' and 'AFT CRG DET.' Based on both the COM 'condition' and the ECAM Status; we both believed that all cargo smoke detection capability was lost (i.e. both CIDS cargo smoke detection channels for FWD cavity 1 and both channels for AFT cavities 1+2). Now; I wonder if this is ambiguous; and if we would have received the SMOKE DET FAULT message if that were the case.After receiving the second ECAM; we contacted the flight attendants; explained the situation; and asked them to walk up and down the cabin and report back if there was any smoke; hot spots; odors; etc. They called back within a couple of minutes and reported none. We asked them to walk the cabin approximately every 10 minutes until we gave them the 'flight attendants prepare for landing' PA.We advised Maintenance Control that we had received the two ECAMs and that there was no evidence of smoke. Maintenance Control replied; asking us to try the reset on COM 3.224.15. We advised Maintenance Control that the reset said it was applicable 'On Ground' only.  Control replied; again asking us to do the reset. We replied; explaining that we were not comfortable with that without them explaining their reasons for requesting this. Maintenance Control replied without mentioning the reset any further; and advised that local Maintenance had been notified of the faults.We discussed the situation; again reviewing that it was unusual to us that we would receive the FWD message; and then a couple of minutes later; the AFT message. We discussed our belief at the time that all cargo smoke detection capability was lost. We considered asking the ground crew; on arrival; to not open the cargo doors until cleared to do so by local Maintenance. However; we discussed that Maintenance would not be able to help us in the extremely unlikely event there actually was fire/smoke. We agreed that; out of an abundance of caution; and to ensure the highest level of safety for our passengers and ground crew we would:1) Request ARFF escort us to the gate.2) Taxi to the gate and deplane normally after landing; without stopping for inspection.3) Instruct the ground crew to not open the cargo doors until cleared to do so by ARFF.We informed the flight attendants of our plan; but stated we would not make a PA to the passengers until after landing; in order to prevent panic/hysteria/uncommanded evacuation. The Captain reviewed with the flight attendants procedures in the highly unlikely event of actual fire/smoke/need for evacuation at the gate. All communication with the flight attendants ensured clear understanding that we only had a detection fault--not an actual smoke indication--and this was merely contingency planning in the extremely unlikely event evacuation became necessary.We messaged Maintenance Control our plan; who forwarded it to Dispatch. We requested they coordinate with both ZZZ ATC to arrange ARFF and with ZZZ Ops to inform the ground crew. Dispatch replied that this would be done.I explained our plan to ZZZ Operations (Ops) when calling in-range. When we checked in with ZZZ Approach; they had not been informed of our situation; so I fully explained our plan to them. We were extremely clear that we were not declaring an emergency. I reiterated our plan to ZZZ Tower; who relayed it to ARFF. After landing; I re-confirmed the plan with ZZZ Ops while the Captain communicated directly with ARFF. I made a PA explaining that airport safety vehicles would follow us to the gate due to a maintenance issue; that there was no cause for concern; and that we would be deplaning normally once we reached the gate.After parking; ARFF contacted us; stating that there was no evidence of fire or smoke; and no hot spots on thermal imaging. They cleared the ground crew to open the cargo doors. I confirmed with ATC that they did not need a written report from the company. The Captain spoke with the ARFF Incident Commander in person; and then called the Chief pilot.Maintenance came on board and began troubleshooting. After engine shutdown; the ECAM Status displayed several items that were not displayed in flight. If I recall correctly; I believe they were INOP SYS 'CIDS' and Class II Maintenance Status messages 'CIDS 2' and 'SMOKE.' After maintenance troubleshooting; the faults were fixed; and we continued on our next leg with no further issue.The COM 'condition' for SMOKE FWD (AFT) CRG DET FAULT should more clearly indicate whether this is a single-channel or dual-channel 'Smoke detection fault.' I would appreciate it if the company could contact Airbus and request clarification of what is the difference between 'SMOKE DET FAULT' and the combination of the two messages 'SMOKE FWD CRG DET FAULT' and 'SMOKE AFT CRG DET FAULT'.The COM procedure for SMOKE FWD (AFT) CRG DET FAULT applicable to our aircraft does match Flight Crew Operating Manual (FCOM) PRO-ABN-26 P 8/70 dated JAN 2015; but neither paper procedure reflects that the ECAM Status page will display FWD (AFT) CRG DET under INOP SYS. This should be investigated.AOM 1.26.50.8 dated Oct 2012 should be updated IAW FCOM DSC-26-50-40 P 1/2. The vast majority of AOM-1 has not been updated IAW [Airbus] FCOM DSC in years. Our outdated AOM-1 refers to a SMOKE LAV + CRG DET FAULT message that can no longer be generated (it is replaced by SMOKE DET FAULT).Maintenance Control should not request that we perform 'On Ground' only COM Supplementary resets in flight without an extremely clear explanation of why they are recommending such action. IAW COM 3.224.3; 'In flight; as a general rule; the crew must restrict computer resets to those listed in the following tables; or to those in applicable OEBs. Before taking any action on other computers the flight crew must consider and fully understand the consequences.'The company should have contacted ZZZ ATC to arrange ARFF; as we requested and Dispatch replied would be done. We should not have relied on the company to arrange this; and should have asked Center to relay this to ZZZ Approach ahead of time.




Synopsis: A First Officer (FO) describes the procedural steps that he and the Captain followed that led them to believe their A320 aircraft had lost all cargo smoke detection capability after receiving two ECAM messages for SMOKE FWD CRG DET FAULT and SMOKE AFT CRG DET FAULT in-flight. The ECAM Status page also displayed; under INOP SYS: 'FWD CRG DET' and 'AFT CRG DET.' After engine shut-down; ECAM Status displayed INOP SYS 'CIDS' and Class II maintenance status messages 'CIDS 2' and 'SMOKE.'