16 February 2013

Mitigating a risk; Airbus drops Li-ion batteries to protect the EIS schedule.

Airbus has decided to drop lithium-ion batteries on the A350 XWB program to protect the EIS- entry into service schedule planned for mid-2014.

Airbus said the concerns did not necessarily center around the technology as such, but were caused mainly by the regulatory uncertainty following the 2 Boeing 787 incidents. Airbus was worried about late additional compliance criteria that could have been introduced by the European Aviation Safety Agency (EASA). The company plans to mature the technology further nonetheless.

Initial flight tests will be performed with lithium-ion batteries, because it is already too late now to implement the change for the early part of the flight test program. However, the A350 will later be certified with Nickel-Cadmium batteries.

“We confirm we are opting for nickel cadmium for the A350 main batteries to protect the programme schedule.  This decision is about protecting the integrity of our program schedule… (it’s not about any safety concerns about Li-ion batteries, we continue in parallel to mature for the A350.  With so much uncertainty raised by the Boeing 787 investigation, we are being prudent in order protect our programme schedule. This is business as usual.”
“As a result of making this decision now, Airbus does not expect it to impact the A350 XWB Entry Into Service schedule,” an Airbus statement added.

This switch of lithium-ion batteries to Nickel-Cadmium batteries also affects to the A320NEO as Airbus stated that the root cause of the 2 incidents occurring on Japanese 787s remains "unexplained, to the best of our knowledge".
The Ni-Cd batteries will be required for flight certification, so they'll be swapped before appropriate certification tests, as initial flight-envelope testing doesn't depend on battery type nor the source of electrical power.

Since Airbus is making this movement as a mitigation plan in a risk-reduction strategy, Boeing needs to prepare a contingency plan as the batteries issue has already impacted 787 production plan and budget and the 787 fleet remains grounded since mid-January.

Airbus will retain battery supplier Saft for the new scheme. Saft had been selected to supply lithium-ion batteries to the A350. Airbus is likely to use a version of batteries designed for the A380 defined as "proven and mastered" nickel-cadmium technology.

Airbus has yet to detail any specific electrical architecture changes which might be required as a result of the switch, but says it is taking the decision early in order to preserve the flight-test and entry-into-service schedule. The weight impact is estimated around 200 pounds / 90kgs.

"Special attention was given to mitigate the identified risks inherent to this technology," it says, adding that it will embark on "additional maturity studies" focusing on lithium-ion battery behaviour.

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