Turboprop manufacturer ATR plans to begin flight tests of its latest ATR-42/72 variant in June.
ATR launched the 42-600 and 72-600 in October 2007 as an upgrade to its -500 models.
No structural changes are being made to the aircraft as modifications centre on a new avionics suite supplied by Thales, higher-thrust Pratt & Whitney Canada PW127M engines, interior enhancements and increased payload.
The enhanced avionics include global navigation satellite system/wide area augmentation (GNSS/WAAS) navigation capability to support required navigation approaches.
Company head of sales John Moore detailed the June flight test earlier this week at the US Regional Airline Association convention.
ATR is engaging in an active certification programme for the -600 ahead of planned entry-into-service date in the second half of 2010.
Certification of the larger 70-seat ATR-72-600 will occur first followed by the 50-seat ATR 42-600.
Sticking to previous forecast, Moore says ATR expects to deliver 60-65 aircraft this year after revising its original estimate of 75 deliveries.