HONG KONG — Cracks appeared Friday in the cockpit window of a 787 Dreamliner flying in Japan, the latest in a string of mishaps with Boeing’s newest and most sophisticated jet.
The plane was operated by All Nippon Airways and was heading from Tokyo to Matsuyama, in southern Japan. The flight, NH585, which was carrying 237 passengers , departed from Tokyo’s Haneda airport at 9:35 a.m. local time and landed safely. No one was injured, a spokeswoman for the Japanese carrier, Megumi Tezuka, said by phone from Tokyo. The return flight, NH590, which had been due to depart just before midday, was cancelled to allow for the screen to be replaced.
Ms. Tezuka added that this was the third time that cracks had appeared in the windshield of one of the 17 787s operated by ANA, after two similar incidents last year.
The cracks appeared on the outermost of five layers that compose the cockpit screen, and did not endanger the aircraft, Ms. Tezuka said. Moreover, cracks of this kind are not unique to the 787 Dreamliner: other aircraft types operated by ANA also have had cracks appear from time to time.
“We do not see this as a sign of a fundamental problem,” with the aircraft, Ms. Tezuka said.
Still, the incident came just days after three other safety incidents involving the aircraft revived concerns about the plane’s reliability and safety.
On Wednesday, ANA canceled another domestic flight using the 787 after an on-board computer mistakenly showed problems with the aircraft’s brakes.
On Tuesday, a fuel leak forced a 787 operated by rival Japan Airlines to return to its gate minutes before taking off from Boston. And on Monday, an electrical fire had broken out on another plane, also operated by Japan Airlines from Logan International Airport in Boston.
The first commercial aircraft to make extensive use of lightweight carbon composites that promise big fuel savings for airlines, the Dreamliner suffered a series of embarrassing delays during its production phase, and has suffered technical and electrical malfunctions since then.
Although the problems so far do not point to serious design flaws with the airplane, they represent an embarrassment to Boeing’s manufacturing ability, analysts have said.
Japan’s Transport Ministry, which oversees aviation safety in the country, said that the frequency of incidents on the Boeing 787 was not particularly higher than incidents reported for other aircraft.
The ministry, for now, did not see any need to raise alarm over the new aircraft’s safety, said Yasuhiro Yamada, an official in the aircraft safety unit.
Before Friday’s mishap, there were just six incidents on record involving Japanese airlines that caused a 787 Dreamliner to alter flight plans, according to the ministry. In two incidents in December, an ANA flight from Tokyo to Seattle turned back because of a temperature rise in the engine’s turbine, while another ANA 787 aircraft suffered a crack in its cockpit window. Nobody was injured in any of the six incidents, which were deemed by ministry officials as minor.
“Even considering that the 787 is a new aircraft, which tends to come with initial glitches, we are not seeing a higher incidence of reported problems compared to other aircraft,” Mr. Yamada said.
He said the ministry continued to monitor incidents on the 787 and all other aircraft, but did not see a need for concern over the Dreamliner’s safety.
Hiroko Tabuchi contributed reporting from Tokyo.
