Bombardier has postponed high-speed taxi tests of the CSeries to at least 5 September, as weather thwarted plans to begin the trials for the second day in a row.
The Canadian airframer says that optimal weather and a dry runway are required for the tests, which was not the case at Mirabel airport today.
Scattered rain showers passed over the airport a little after midday today, weather radar on The Weather Network shows.
Bombardier hopes to begin high-speed taxi trials on 5 September subject to the weather conditions, it says.
The forecast for Mirabel is partly cloudy with a 20% chance of showers on 5 September, according to The Weather Network.
Bombardier received a flight test permit for the CSeries from Transport Canada on 30 August. The permit allows the OEM to conduct the high-speed trials as well as first flight once all ground testing is complete.