Date: 201508
Location: ZZZZ.Airport, FO
Light: Daylight
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Landing Gear
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Aircraft Equipment Problem Less Severe
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: After departure; following gear retraction; we noticed a louder than normal airflow-like noise in the cockpit; accompanied by a very light rumbling. We looked over the forward panel and upper and lower ECAM . Everything looked normal. We also looked periodically through the ECAM system pages. Nothing out of the ordinary. Contacted dispatch via ACARS text; and wrote that we had a slight rumbling along with some noise. Nothing indicative of a problem. As we neared [an] intersection; we were told by controller to contact [Commercial Radio]. Shortly thereafter; we lost our vhf and ACARS; however we were aware that we could use HF to get info to our dispatcher. Prior to coasting out; I told the dispatcher that there weren't any indications of any problems. We were around 2 1/2 hours late; and felt that the ground crew had left an access panel open. We concurred with dispatch and MOC that if no problem exists; we can fly at .76/FL320 (conflicting traffic at our planned cruise of FL360). We also noted that our projected fuel at [the intersection] was within 300 pounds. We incurred a long sit on the ground; so this slightly excess burn seemed plausible. The last message we received before coasting out said to the effect if you feel comfortable at .76/FL320 that is ok; if any doubts; then we would have to establish a new plan.At top of climb; I conducted ECAM system checks; paging through the system pages and noted nothing unusual. I kept a fuel log; and noted that we were within about 500 lbs of planned burn during the early part of the flight. This increased to 700 later over [another fix]; but I think we were in radar contact I believe by that time.About halfway through the flight; I asked the Flight Attendants (FA) if they heard anything or felt anything unusual. They said that they did not. I told them that we had a lot of noise and a slight rumbling up in the cockpit; but no other indications. I made my first logbook entry while still out of radio contact: 'After Takeoff and at all times during flight; light rumbling and loud noise in cockpit. FWD Galley FA did not hear anything.' We still believed the source to be an open panel at this time.As we neared land; we began to catch up with the ACARS messages that were interrupted after our departure from ZZZZ. Dispatcher recommended I fill out a vibration report. I began to do that. I had conducted at least 2 other ECAM system flows and noted nothing irregular on either one of these.  Dispatcher asked if we needed anything; and I said that we were just fine. About 200 miles from [Destination]; and after several messages to dispatch; I conducted another ECAM systems check; feeling very confident it was only an open access panel. When I came to the WHEEL page; I noticed 4 amber x's above the nosegear. This was the first time we had seen anything abnormal. We slowed the aircraft down to .67M/280 KIAS; notified ATC. We entered the discrepancy in logbook.ATC was aware of our situation; but we elected to treat it as a normal procedure unless the gear would not extend/lock. The gear came down with normal indications. We landed; taxied to the gate and everything was normal up to that point. At shutdown; we received the only ECAM message during the entire flight: L/G SYS DISAGREE. We entered that in logbook; and maintenance was waiting for us when the door opened.




Synopsis: A320 Captain reported noticing slight vibration after takeoff; and later in the flight received the ECAM message L/G SYS DISAGREE. Approach and landing were normal.