Qatar Airways is reducing the frequency of more than a dozen regular routes from Doha because of hold-ups in the delivery of new planes from European manufacturer Airbus, an airline spokesperson said on Sunday. The 15 affected routes include the carrier's recently launched service to Adelaide in Australia, flights to Boston, Houston and Miami in the United States, and services to Copenhagen, Jakarta and Manchester."We are making selective flight cancellations in several markets ... due to a delay in Airbus aircraft deliveries," the spokesperson said in a statement."We are minimizing the impact on our passengers as much as possible, and accommodating them on other flights that suit their travel needs. The flight cancellations are taking the form of one flight per week in most of the affected markets through the summer."CEO Akbar Al Baker said last month that Qatar Airways was speaking to Boeing about securing aircraft to replace an order of Airbus A320neos because of problems affecting hydraulics and software. Qatar Airways was due to receive the first of 50 A320s in December but refused to take delivery after saying the U.S. Pratt & Whitney engines supplied were inadequately tested for the Gulf region's high temperatures.