The second Comac C919 prototype will take its first flight imminently, in-line with the original target of an end-2017 maiden sortie.
The Chinese manufacturer tells FlightGlobal that all is in place for Flight Test Aircraft two (FTA-2) to fly "over the next few days".
Last week, Comac America tweeted that the CFM International Leap-1C-powered aircraft had completed medium-speed taxi tests in Shanghai, and projected its first flight, weather permitting, for the end of the week of 11 December.
On 15 December, it gave an update that there has been "a slight adjustment" to the aircraft's flight test schedule, which will push first flight back from Friday. It adds, however, that take-off "is still imminent".
Comac powered up FTA-2's engines in November, and has been conducting taxi tests with the aircraft at Shanghai Pudong International airport.
The first C919 prototype flew to Xian on 10 November, where the next phase of flight tests and certification work will take place.
Comac will use six test aircraft for the C919 programme, which is targeting to obtain certification around 2020-2021. The C919 has 785 commitments from 27 customers.