Vietnam Airlines expects it will have to wait until 2015 to receive its first Boeing 787 after switching its 16-aircraft order from the -8 to the stretched -9 due to unexpected performance limitations on the original model.

The government-owned flag carrier first ordered four 787-8s in 2005 for delivery from 2009. In 2007 Vietnam Airlines ordered four more 787-8s and Vietnam Aircraft Leasing ordered eight 787-8s on behalf of the carrier.

Vietnam Airlines CEO Pham Ngoc Minh says its 787 deliveries have since been delayed six times by Boeing and the carrier has had to switch to the -9 because the -8s no longer meet the carrier's performance requirements. Minh explains the -8s are now too heavy to economically operate long-haul routes from Vietnam to Europe and North America.

"The -8 doesn't meet the performance guarantee as they told me," Minh told Flightglobal on the sidelines of this week's SkyTeam meeting in New York. "We found the -8 is a heavy -8; it's not the original -8 they committed to."

The bigger 787-9, which follows the 787-8 in development, is now scheduled to enter service at the end of 2013. But Minh says Boeing is only offering Vietnam Airlines -9 slots from 2015.

He says Vietnam is trying to speak to Boeing about moving up to earlier 787-9 slots but so far it has been difficult to get a firm plan from the manufacturer. "They've delayed six times already. I don't know how many more times they will delay," he says.

For now Boeing still lists all 16 787s ordered by Vietnam Airlines and Vietnam Aircraft Leasing as -8s. It is not clear why Boeing has not formally changed the order to -9s but the manufacturer could be waiting to conclude a re-negotiated deal with its Vietnamese customers that may also include new Boeing 777s.

vietnam 787

 © Boeing

Minh says waiting until 2015 "is not our requirement" and "in the interim we continue to negotiate with Boeing".

He adds Vietnam Airlines is now looking to expand its Boeing 777-200 and Airbus A330 fleets to fill the gap caused by the extensive delivery delays to its 787s. Vietnam Airlines also has 10 A350-900s on order but Minh says these are not scheduled to be delivered from 2014, or only slightly ahead of the carrier's first 787-9.

Minh says Vietnam currently operates 20 widebodies - 10 777-200s and 10 A330s - but its fleet plan includes at least 40 widebody aircraft by 2015. Vietnam requires the 20 additional widebodies over the next five years - plus another 15 to 20 widebodies in the 2015-2020 timeframe - to meet an ambitious expansion plan that will see the carrier launch new routes to Australia, Europe and North America.

"With manufacturers it's sometimes difficult for me to push them, especially for next-generation because for next-generation they have certain difficulties. But the market is there and we have an ambitious plan," Minh says. "We can't wait. We have to add more A330s and maybe more 777s until the time we can replace all of it."

He adds Vietnam Airlines plans to use its 787-9s and A350-900s on similar missions but the carrier needs to acquire both types because neither manufacturer has enough slots to meet the carrier's requirement for 55 to 60 widebodies by 2020.