787 Problèmes électriques

Boeing is on the verge of flight testing the modified 787 battery
system changes on Line Number 86, an aircraft destined for LOT Polish
Airlines. The aircraft is set to undergo a final pre-flight ground test
in the afternoon (Pacific time), at Paine Field, Everett on 24th, and if
all goes to plan could be cleared for a standard ‘B2’ profile, customer
acceptance type flight test on March 25.

Boeing originally hoped to conduct this flight test on either the 23^rd
or today, but evidently is working its way through last minute issues
before conducting the flight test. Ground tests of the electric and
electronic equipment (E/E) bay are also underway on a Japan Airlines 787
at Paine Field, though it is not known if these are directly associated
with the on-going certification efforts for the battery modification,
or simply part of the regular pre-delivery tests as Boeing gets set to
resume production flight testing.

Boeing on March 25 conducted a functional check flight of a 787
fitted with the revised lithium-ion battery system as a preliminary step
toward a certification demonstration flight planned for the coming
days.
The Boeing-owned aircraft, Line Number 86, destined for LOT
Polish Airlines, made the relatively short flight around the Washington
and Oregon coast test areas following a final series of pre-flight
ground tests at Paine Field, Everett, on March 24. Boeing says the
flight, which began at 12.11 p.m., was “a normal Boeing production check
flight intended to validate that all systems function as designed.”
During the roughly two-hour sortie, the crew checked the back-up systems
and cycled the landing gear, as well as performed electrical systems
checks.
In a statement, Boeing says that “following the completion
of the functional check flight, we will analyze the data from the
flight and prepare for certification ground and flight demonstration in
the coming days. The plan is to conduct one certification demonstration
flight. That flight, which will take place on Line 86, will demonstrate
that the new battery system performs as intended during flight
conditions.”
At Boeing Field, close to Seattle, the company also
is preparing 787 development test aircraft ZA005 for ground tests of the
revised battery–particularly the new stainless steel enclosure and its
associated venting system. There has been no notification about when
specifically this might occur, although the company says it aims to
complete both the certification flight test and associated ground test
“in days.”
Pending completion of certification and FAA approval
for the battery system modifications, Boeing aims to immediately restart
production test flights at Everett, as well as its North Charleston,
S.C., production facility. Several production test flights also are
scheduled for 787s that have been stored at a paint facility near Fort
Worth for the duration of the grounding of the fleet following two
separate battery failures in January.
Separately, the NTSB said
its upcoming forum, “Lithium-Ion Batteries in Transportation,” will be
held April 11-12. The NTSB event, which was announced on March 7 when
the safety board released its interim factual report on the Jan. 7 Japan
Airlines Boeing 787 battery fire investigation, will focus on design,
development and performance of the batteries, as well as related
regulatory and safety aspects of the technology.

Admin a écrit: ... ce point n'est pas anodin ...

The Japan Transport Safety Board’s probe into the emergency landing
of an All Nippon Airways Co. Boeing 787 said no faults were found in the
aircraft’s electrical system after a lithium-ion battery overheated
under the cockpit.

The board said Wednesday there might have been a defect either inside
the Dreamliner’s battery or in the way it was connected to its charger.

“When the problem occurred, there was no external flow of current
from the battery and it was only connected to the battery charger,”
Norihiro Goto, the safety board chairman, told reporters in Tokyo. “We
can only think of two possibilities — that (there might have been a
fault) either inside the battery or in its connection to the charger.”

The board also said that about 10 holes apparently caused by sparks
were detected in the stainless-steel battery case, which melts at around
1,400 degrees.

Boeing’s 787s have been grounded worldwide after the ANA Dreamliner
made an emergency landing in Kagawa Prefecture on Jan. 16 due to smoke
in the cockpit. The lithium-ion battery under the cockpit was later
found to be severely damaged and charred.

Beochien a écrit: ... Une nouvelle electrolythe directement venue de l'espace, constitue un changement majeur, totalement insensible à la dentrite, même aigüe , dont la composition, longtemps maintenue secrète, serait : Lithium-Ion de Kryptonite