Malmö Aviation (TF, Malmö) has dealt Bombardier Aerospace (BBA, Montréal Trudeau) a blow with an announcement stating it will no longer be the AC!CS1's launch customer. The Swedish regional operator, which has five CS100s, five CS300s, and options for ten more aircraft with the Canadians, said concerns over recent engine problems in the type's test-flight regime had led to the deferment.

"It has subsequently emerged that this may cause another delay to the CSeries introduction," Braathens said in its second-quarter 2014 report. "We have informed Bombardier that we will not assume the role of formal launch operator of the aircraft type."

According to Reuters, parent firm Braathens Aviation is in talks with Bombardier about other possible changes to the delivery schedule. Malmö Aviation was scheduled to receive its first CSeries in either July or August 2015.

Bombardier announced in January that the CS100's entry into service date would be delayed until the second half of 2015. However, a May 29 Pratt & Whitney PW1500G engine failure during a test flight has led to fears the aircraft's commercial début will be further delayed.