Boeing has completed cold soak tests of the 737-600 and says it is on track to complete US Federal Aviation Administration certification by mid-August.
The US airframe builder used the US Air Force's climatic test site at Eglin AFB, Florida, to obtain constant temperatures of -35°C.
"We were required to get a minimum of 8h cold soak, but we ended up with around 24h on the left engine and 16h on the right," says flight test operations unit chief John Brummer. "The engines started right up and ran at idle with no problems."
The third 737-600 recently flew to Mesa, Arizona, to test - successfully - solutions to a floor vibration detected on earlier sorties and undertake a series of flights that included community noise tests.
By early July, the three test aircraft had been flown for 670h of a planned total of 779h before certification. European Joint Aviation Authorities certification is expected soon after FAA approval is given, around late August, in time to allow first deliveries to SAS to be made in September.
Source: Flight International