Certification of the seven-seat Grob G160 Ranger turboprop single has been delayed from this quarter to the middle of next year to incorporate a new interior design and aerodynamic refinements. These changes stem from flight-test results gathered since the prototype G160’s first flight in March last year.

The improvements, announced in late June, mainly include the addition of winglets and “other refinements” that provide optimal performance across the flight envelope. Inside, the new interior design sports leather seats similar to those of the Grob SPn Utility Jet unveiled at the Paris Air Show in June. At press time, a prototype SPn was undergoing taxi tests in preparation for first flight.

Powered by an 850-shp Pratt & Whitney Canada PT6A-42A engine, the G160 Ranger will have a 270-knot cruise speed and 2,200-nm maximum range.

Meanwhile, certification of Grob’s unpressurized G140TP turboprop single has also been delayed from this summer to the second half of next year. A spokesman told AIN that there aren’t any technical snags with the program; rather, it has been put on hold due to lagging sales of the aircraft.

For now, he said, Grob has shifted its flight-testing priorities to the SPn program, reflecting the belief that jets are the company’s future. This new focus relegates both in-development turboprop single entries to the back burner in the mean time.