SEATTLE — Boeing has been awarded U.S and European type certification for the 787-9, the first major derivative of the 787 family, clearing the way for delivery of the initial aircraft to launch customer Air New Zealand.

Certification of the 787-9, a 20-ft. stretch of the baseline 787-8, follows a nine-month long flight test program which began with the first flight of the model on Sept 17. In all, five aircraft have been involved in the approval program which included two production aircraft with interiors. These involved ZB197, a Rolls-Royce powered aircraft which was used principally for ETOPS and function and reliability (F&R) tests, and ZB167, a General Electric-powered aircraft which has also been involved in F&R and electro-magnetic effects testing.

The flight-test effort, which included more than 1,500 flight hours, was significantly shorter than that of the baseline 787-8 which was certificated in August 2011 after a 20-month program. Testing of the 787-9 was also virtually trouble free, though the campaign unearthed minor issues which forced Boeing to request FAA exemptions for two components that currently do not meet airworthiness regulations. These included the ram air turbine (RAT), an improved version of which will be introduced into service in February 2015, and an altitude selector knob on the autoflight mode control panel which will be superseded with a new design the following May.

Certification also clears the 787-9 immediately for ETOPS (extended operations) flights up to the 330 minutes away from a diversion airfield. The approval of extended ETOPS "out of the box" formed the final element of the FAA certification process, notification of which came on June 13. The 787-8 entered service with 180 minutes ETOPS and was only cleared by FAA and EASA for the full 330 minutes last month.

Part of the safety analysis that went into the latest clearance for the 787-9 included assessments of the potential likelihood of having to use the RAT, says Boeing 787 chief project engineer and vice president Bob Whittington. The company’s analysis indicates that, combined with the relatively small size of the 787-9 fleet that will have entered service by early 2015, the probability of the RAT being used over the period is in the region of one in a trillion.

"You have to lose six generators before you need the RAT," says Whittington, who explains that the capacitor in the emergency turbine found to be at fault only showed evidence of degrading after being used several times during flight testing — a circumstance that an in-service aircraft would never experience.

Although Boeing will formally exchange contracts for the first 787-9 at the end of June with Air New Zealand, the actual delivery flight is not expected to occur until the week beginning July 7. The aircraft will then be involved in some route proving and crew training flights before a limited number of "surprise" one-off services to Australia begin in August. More extensive long haul flights are expected to begin shortly thereafter. The first carrier to put the stretched aircraft into service is therefore likely to be All Nippon Airways which is also due to receive its initial aircraft in July. Air New Zealand has yet to operate any version of the 787, while ANA now has more experience of the type than any other airline. To-date 413 787-9s are on firm order, or 40% of all 787 orders.