05/30/2014 03:54 EDT | Updated 07/30/2014 05:59 EDT

Bombardier CSeries test plane grounded with 'engine-related incident'

The testing program for Bombardier's upcoming CSeries jets has been temporarily halted after what the company called "an engine-related incident" on one of the test planes during maintenance work in Mirabel airport north of Montreal.

"Bombardier is investigating the incident with the support of Pratt & Whitney and the appropriate authorities," the company said in a statement. "Safety is the priority, and the CSeries aircraft flight test program will resume once the investigation is completed."

Originally scheduled for commercial delivery in late 2012, the CSeries is Quebec-based Bombardier's ambitious narrow-bodied, twin-engine medium range jet model, tailored toward a growing market of business travellers.

The company began its first real-life flight tests for the prototypes last fall, and is trying to convince airlines to transfer their aging fleets.

Bombardier shares shed almost four per cent to trade at $3.68 on the TSX on Friday.