The US Federal Aviation Administration (FAA) has approved Boeing's certification plan for the redesigned 787 Dreamliner battery system, a move to accelerate Boeing's efforts to end a nearly two-month long grounding of the aircraft.
The redesigned battery system includes improved insulation of the cells, a redesign of the internal battery components to lower initiation of a short circuit within the battery, and a new containment and venting system.
The FAA stated that approval was given after thoroughly reviewing Boeing's proposed changes and the plan to demonstrate that the system would meet the agency's requirements.
Its certification plan is the first step to assess the 787's return to flight, FAA added.
There are calls in the plan for a series of tests that must be passed prior to the 787 return into service and requires Boeing to conduct testing and analysis to demonstrate compliance with the applicable safety regulations and conditions.
US Transportation Secretary Ray LaHood said the comprehensive series of tests would demonstrate whether the proposed battery improvements will work as designed.
"We won't allow the plane to return to service unless we're satisfied that the new design ensures the safety of the aircraft and its passengers," LaHood said.
FAA Administrator Michael P Huerta said: "We are confident the plan we approved today includes all the right elements to conduct a comprehensive evaluation of the battery system redesign."
The certification plan builds on specific pass/fail criteria, states the parameters that should be measured, defines the test methodology and specifies the test setup and design.
In addition, the FAA has approved limited test flights for two aeroplanes, which will have the prototype versions of the new containment system installed.
The purpose of the flight tests is to validate the aircraft instrumentation for the battery and its enclosure testing, in addition to product improvements for other systems.
FAA stated that it would approve the redesign only if Boeing successfully completed all the required tests and analysis to demonstrate the new design that complies with FAA requirements.
The airworthiness directive issued on 16 January this year, which called on operators to temporarily ground the 787 Dreamliner operations, is still in effect and the agency is continuing its comprehensive review of the 787 design, production and manufacturing process.
Image: FAA stated that it will approve the battery redesign for 787 only if Boeing successfully completes all the required tests and analysis. Photo: courtesy of Boeing.