Airbus Industrie Undifferentiated or Other Model
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 26
Confusion
Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance
Aircraft; Human Factors; Procedure
Aircraft X leveled off at FL210 about 18 miles west of MOL. I then waited for at least two radar updates and then issued a descent via the Spider1 landing south Richmond airport. After the clearance was read back the AirBus started a very slow descent; 209; 208; 207; and then shot backup to FL210. No other aircraft in the vicinity and other than an altitude deviation; no harm done. But; we have had many issues with [Another Airline] Airbus aircraft descending into the Charlotte; NC. Airport missing their altitudes that I thought that this Aircraft X Airbus should be tested. As if on cue; once the aircraft was flat and level; it started to descend. This issue seems with Airbus only.Have Airbus look into and fix the issue before a midair happens and a loss of life happens. The FAA should be a leader on this and not a reaction to this possible event.
ZDC Controller describes an aircraft given a descent clearance; the aircraft descending; and then climbs back to old assigned altitude. Controller thought this a company problem; but this aircraft was the same type; but a different company.