- JAL Tokyo to San Francisco flight diverted to Honolulu after engine oil pressure dropped
- Pilots shut down engine and requested emergency landing, as per airline protocol
- Comes after wing cracks discovered in 40 in-production planes
A Boeing 787 Dreamliner operated by Japan Airlines (JAL) was forced to land prematurely in Hawaii, after pilots shut down one of its engines.
Flight JL002 with 171 people on board was en route from Tokyo to San Francisco when an oil pressure warning was received, forcing the pilots to terminate the flight eight hours in.
"At the approach to Honolulu the oil pressure was getting low, so the engine was shutdown," a JAL spokesperson told CNN.
"When one engine of an aircraft with twin engines is stopped, the airline must declare an emergency so the flight can have priority to be guided by air traffic control and apply for landing.
"There was no injured passenger or crew.
"It was not battery trouble; the cause is being investigated."
Hairline cracks discovered
The diversion came just days after Boeing's announcement that hairline cracks had been found in the wings of 40 in-production planes.
While teething problems are common with most new models of aircraft -- the Dreamliner fleet was famously grounded in January 2013 after numerous problems with its battery -- Boeing admits that reliability is a work in progress.
"The Dreamliner has a dispatch reliability rate of 98%," Rob Henderson, Boeing's communications director Japan told CNN.
"But we're improving that all the time, to get it up to where the 777 and 737 are -- above 99%."
Dispatch reliability is the percentage of planes that leave within 15 minutes of the scheduled takeoff time, assuming no technical reasons for delay.
The Dreamliner has a dedicated "Operations Control Center" that helps assist with problems as they occur.
"The center monitors every 787 in flight; it identifies problems and works with the airline to provide maintenance, sometimes even in flight," said Henderson.
Part of the Dreamliner's problem has been due to heightened media scrutiny, says Tom Ballantine, chief correspondent at Orient Aviation magazine.
"Because of the early dramatic grounding of the plane every little thing that happens now gets reported," he told CNN.
"But the Dreamliner hasn't really become a total nightmare. New models do historically have a lot of teething problems.
"The 747 had quite a few issues when it first entered service, and hairline cracks were also found in the wings of Airbus A380s (along with other problems). But none of this was a threat to the safe operation of the aircraft, which were repaired during downtime."
"These issues with the 787 are certainly frustrating for the airlines but you can be sure they are being well compensated. All the airlines I have spoken to think it's a great plane with a fantastic future."
JAL said it was working with Boeing to identify the issue with the engine.
The plane would remain parked at Honolulu until the issue had been resolved, it added.