Date: 201905
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Aircraft: A321
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Climb
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Human factors: Situational Awareness; Training / Qualification
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Fuel Issue
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem
Contributing factors: Human Factors; Aircraft; Manuals; Procedure
Primary problem: Human Factors

Narrative: Fuel Imbalance Advisory; Initial Climb. Fuel Page pop-up on lower display; without ECAM (Electronic Centralized Aircraft Monitor).Initial Climb departing ZZZ to ZZZ1. Imbalance indicated between tanks L6+; R8+.Normal all pumps on; cross-feed closed. Tank feeding each engine. Release fuel was 16.1. Question is do you believe the quantities display? Tanks added to a reasonable total; reference Release fuel. Could not justify imbalance due to a trend; leak etc. CA (Captain) as PM (Pilot Monitoring); decision to cross-feed re-balance during climb. Correct system response would determine if continued flight was indicated or divert ASAP before imbalance/Non ECAM problem worsened. Cross-feed re-balance corrected imbalance and arrival at ZZZ1 with correct flight planned fuel and balanced. Crew recollection is of checking fuel on preflight; but maybe due to refueling still in progress; if Imbalance was indicated; did not notice final imbalance; as we assume created the event. Post flight info; fuel slip indicated L8.0 + R8.0 = Release fuel (CA called ZZZ Ops Supr (Operations Supervisor); to inquire of what fueling slip indicated)). Gate shutdown post flight called Maintenance Operations to relay events and inquire about AML inspection/entry. Advised systems functioned correctly. Later; after calling ZZZ Ops and learning of fuel slip entries; called 320 Fleet Manager with the event details and conflicting Information. He informed of some rare probe indication problems and would follow-up this event. Question; if imbalance after start indicated above lower takeoff limitation....why would AB wait to advise until climb? In flight much higher limitations! One tank feeding each engine; subsequent instant big imbalance improbable? Crew missed imbalance after late refueling or fuel slip recorded L8+R8; if correct; sensors reported incorrectly until airborne? Personally check bleed page post-start; due to AB anomaly's that amber indications can be present without crew notification. Experienced a pack flow control valve amber after start and continued single pack operation; without ECAM or INOP (Inoperative) status messages. This previous event discovered during FL390 (39;000 ft) cruise system checks; told was a logic protection normal function; AB was within limitations? Precautionary; descended to FL310 IAW (In Accordance With) single pack Dispatch guidance. Training CKA (Check Airmen) know of these anomaly's; recommended SOP (Standard Operating Procedure); after start system page check! Double that recommendation.




Synopsis: Flight Crew flying A321 observed fuel imbalance inflight.