Date: 201304
Flight conditions: VMC
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Aircraft component: Central Warning/Master Caution
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Troubleshooting
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: Approaching cruise altitude; I noticed an intermittent flashing near the flap position indicator on the E/WD. It flashed in amber Flap - F above and F-Locked below the symbol. It then alternated to flash Flap - S and S-Locked. There was no associated ECAM to confirm a failure or fault of the system. No C/B's had popped. I checked the F/CTL system display page. All was normal. I disconnected the autopilot to confirm that there were no flight control abnormalities. There were none. The flap position indicator showed everything stowed; and I confirmed that. The flashing persisted. We then got an ECAM with aural chime for COND AFT CRG ISOL VALVE. It; too; was intermittent. The system display page showed both valves continuously closing and opening. We were unable to clear the intermittent ECAM normally or silence the chime using the emergency cancel button. The two problems; although completely separate systems; were both randomly flashing with the one ECAM chiming. This made us wonder if there was an underlying related electrical issue even though all other system pages showed normal operation. I had earlier sent a message briefly describing the problem to Maintenance Control through ACARS; but eventually I determined the need to speak directly. I requested a phone patch to Maintenance Control. I had been PF; so I gave control of the aircraft and ATC radios to the First Officer. I talked through the problems we were experiencing so far with Maintenance Control. He took several moments to reference the systems. There was a discussion to determine whether the flaps/slats had locked up; but without a corresponding ECAM failure or fault and nothing highlighted as a fault on his end. It was agreed that it was more likely an indication problem. For now; the COND AFT CRG ISOL VALVE was considered to be a separate issue with the only action of crew awareness. We referenced the flight control system flap/slat chapter of the Flight Manual; but there was no information regarding this scenario of flashing lights. Maintenance Control guided me to cycle flap/slat control CB's to clear the flashing indication. I was somewhat distracted by the continuous chime and flashing; but at the time; this seemed a reasonable course of action as I had confirmed the flaps were up. I proceeded to cycle the C/Bs using Maintenance Control's instructions and my Captain's Emergency Authority in attempt to silence the warnings as I felt a sense of urgency with the two issues occurring simultaneously. It did not correct the flashing. Maintenance Control continued to reference the Flight Manual. Meanwhile; I became even more concerned that there could be some connection between the two issues and some larger underlying problem. The first officer agreed. She requested a lower altitude with ATC while I considered diversion airports to give us options in light of the situation and in the event the situation deteriorated. During this time; we had to transfer us to another frequency due to a medical emergency for another aircraft. After several minutes; I reconnected with Dispatch/Maintenance Control. Maintenance Control came back on the radio suggesting that it might be one of the Flight Warning Computers. While this discussion was going on; other systems then started to intermittently flash and chime. The ones that I remember included: nose wheel steering disconnect message; a BRAKES HOT; and an AIR PACK 1 OVHT ECAM. There was no supporting information that corroborated these ECAMS or messages on the system pages. They were intermittent except for the AIR PACK 1 OVHT. It stayed on; so I completed the ECAM and shut off Pack 1 per procedure. I relayed this new information to Maintenance Control. The suspicion that we had issues with the FWC's seemed more plausible. My sense of urgency to understand the problem before deciding with the F/O to divert due to electrical issues continued; but by now we were well into the arrival; making our destination the most suitable airport. I wanted a long runway to land with zero flaps/slats if that scenario were to present itself. We continued to work to understand the problem. Maintenance Control gave me reference to the FWS FWC 1(2) FAULT procedure. Per this procedure and Maintenance Control guidance; I cycled the FWC C/Bs separately. This resolved the additional random issues; but the original flashing of the flaps/slats and the AFT CARGO intermittent ECAM remained. It was at this point I returned our attention to the flap/slat issue. Even though we felt it an indication problem; we discussed the possibility of a no flap/slat landing. I had acknowledged and discussed this possibility with Maintenance Control. The First Officer pulled out the expected non-normal procedure; F/CTL FLAPS FAULT/LOCKED; to review in case that ECAM should occur. There was nothing left to address further with Maintenance Control; so we both signed off. I continued the conversation with Dispatch. Dispatch was able; with our ATC coordinator; to forward our request for the long runway. If we had issues with flaps/slats on approach; I would elect to declare an emergency then and request appropriate assistance. Upon switching to Approach Control; I requested to slow early to extend flaps/slats. Flaps/Slats extended normally; and we landed without incident. After the flight I further reviewed the Flight Manual and found that the flap/slat control CBs were not to be cycled in flight. I was unaware of that restriction at the time Maintenance Control advised me to cycle them. There was never a defined ECAM or unannunciated procedure to follow. There was a sense of urgency to silence the warnings yet mindful consideration to understand the cause of the random indications. In hindsight; it was an unintentional failure on my part to not question the guidance/direction to cycle flap/slat control C/Bs. A flag went up in my mind at the time; but it was not immediately apparent to me that these were of prohibited status in regards to cycling while in flight. At the time; I relied on and trusted my resources with that information to make a judgment call when I exercised my Captain's Emergency Authority to cycle those C/Bs. Maybe those C/Bs should be highlighted in some way on the CB panel and/or within Maintenance Control procedures to alert us to their prohibited status in flight. I talked with Maintenance Control directly on the phone after the flight to explore further his thought process for this guidance. He mentioned that he thought we were on the ground when he suggested we cycle those C/Bs. This concerned me as I had assumed he knew that we were airborne based upon my initial contact and phone patch through Dispatch and lengthy discussions. It's clear there was a misunderstanding and communication error here.




Synopsis: An A320 had an intermittent Flap/Slat Locked indication in cruise; followed shortly by an intermittent COND AFT CRG ISOL VALVE warning. Maintenance Control suggested cycling the flap/slat control circuit breakers; to no avail. New ECAM's appeared; including nose wheel steering disconnect message; a BRAKES HOT; and an AIR PACK 1 OVHT. The AIR PACK 1 OVHT ECAM was complied with and the others were cleared by cycling the FWC (Flight Warning Computer) circuit breakers. A landing at destination with normal flap operation was made.