Qatar Airways grounded an additional <a href="https://www.thenationalnews.com/business/aviation/2022/01/21/airbus-cancels-qatar-air-order-for-50-a321-aircraft-as-dispute-escalates/" target="_blank">Airbus A350 aircraft</a> after the country's civil aviation regulator revoked the jet's Airworthiness Review Certificate amid a continuing dispute with Airbus. The move brings the total number of A350 jets grounded by the airline to 22, as the <a href="https://www.thenationalnews.com/business/aviation/2022/02/19/uk-judge-orders-airbus-to-delay-cancellation-of-6bn-qatar-airways-jet-order/" target="_blank">dispute</a> between the airline and the European manufacturer over damage to the surface of the long-haul jets continues to escalate. "This decision has been taken by our regulator as all of these aircraft have developed damage as a result of the A350 Accelerated Surface Degradation Condition, which is beyond the tolerance limits set by Airbus," the airline said in a statement on Monday. The regulator "will not allow these aircraft to return to service until a full and conclusive root cause analysis has been completed, the impact on continuing airworthiness has been established and a solution been found to permanently correct the root cause and repair the damage". The row has spilled into a legal battle playing out in a division of London's High Court and has spread to a contract between Airbus and Qatar Airways for A321neo narrow-bodies. In January, <a href="https://www.thenationalnews.com/business/aviation/2022/01/21/airbus-cancels-qatar-air-order-for-50-a321-aircraft-as-dispute-escalates/">Airbus revoked a deal with Qatar Airways </a>for 50 A321neos, saying its refusal to take disputed A350s had triggered a clause linking the two plane deals. Earlier this month, Qatar Airways <a href="https://www.thenationalnews.com/business/2022/02/01/boeing-secures-record-777x-freighter-deal-and-bags-737-max-order-by-qatar-airways/" target="_blank">placed an order</a> for 50 Boeing 737 Max 10 jets, giving the US plane maker an edge over its rival, Airbus. "Qatar Airways will continue its legal action to seek an order that requires Airbus to fully, properly and transparently investigate the A350 Accelerated Surface Degradation, to establish the conclusive and full root cause of an important condition which is degrading the surface of the aircraft beneath the paint," the airline said. Qatar Airways discovered the defects last year when it sent one of its A350 aircraft to be repainted with World Cup livery. Airbus acknowledged the issue, conducted studies and offered remedies but insisted that the flaws did not represent a safety issue. Other airlines, including Air France, Cathay Pacific, Finnair, Lufthansa and <a href="https://www.reuters.com/business/aerospace-defense/european-regulators-propose-check-anti-lightning-flaw-some-a350-jets-2021-12-06/">Delta Air Lines</a>, have raised concerns about surface flaws on the A350 jet, according to <a href="https://www.reuters.com/article/airbus-a350-insight-idTRNIKBN2IE0TB">Reuters</a>. ____________________