Bombardier recorded its first significant Farnborough order for the new CSeries on Sunday. A yet-unidentified customer signed a conditional commitment for five CS100s and ten CS300s.

The order brings the CSeries total commitments to 153 aircraft from 13 customers. Bombardier has recorded slightly more orders for the larger CS300 version, which can seat up to 149 passengers. Including the new deal, Bombardier now has 82 CS300s in its backlog and 71 CS100s, although it is too early to call this a trend.

The CSeries is planned to make its first flight before the end of this year, although Bombardier Aerospace’s President Guy Hachet said in an interview that there was no more margin left in the schedule. The manufacturer has highlighted difficulties in fly-by-wire software development that has required additional work.

Also, Bombardier has started assembly of components and fuselage sections, but has not yet entered into the aircraft final assembly process.

There are questions regarding the readiness of the Chinese part of its supply chain, too. The first fatigue test unit is to be ready by September. Completing that work for the first flight test aircraft within four months is seen by many industry observers as unrealistic.