The US FAA has grounded US operators of the Boeing 787, saying it will issue an emergency airworthiness directive (AD) to address a potential battery fire risk.

In a statement, FAA said all US-registered operators of 787s must temporarily cease their Dreamliner operations.

“Before further flight, operators of US-registered, Boeing 787 aircraft must demonstrate to the FAA that the batteries are safe. The FAA will work with the manufacturer and carriers to develop a corrective action plan to allow the US 787 fleet to resume operations as quickly and safely as possible,” it said.

United Airlines is the only current US operator of the 787, with six aircraft in service. When the FAA issues an airworthiness directive, it also alerts the international aviation community to the action so other civil aviation authorities can take parallel action to cover the fleets operating in their own countries.

A United spokesman issued this statement: “United will immediately comply with the airworthiness directive and will work closely with the FAA and Boeing on the technical review as we work toward restoring 787 service. We will begin re-accommodating customers on alternate aircraft.”

FAA’s statement added the AD was prompted by the Jan. 16 inflight All Nippon Airways (ANA) battery incident, which followed the Jan. 7 Japan Airlines (JAL) 787 battery incident that occurred on the ground in Boston.

The statement continues: “The AD is prompted by this second incident involving a lithium ion battery. The battery failures resulted in release of flammable electrolytes, heat damage and smoke on two model 787 airplanes. The root cause of these failures is currently under investigation. These conditions, if not corrected, could result in damage to critical systems and structures, and the potential for fire in the electrical compartment."

Last Friday, the FAA announced a comprehensive review of the 787’s critical systems with the possibility of further action pending new data and information.  In addition to the continuing review of the aircraft’s design, manufacture and assembly, the agency also will validate that 787 batteries and the battery system on the aircraft are in compliance with the special condition the agency issued as part of the aircraft’s certification.

Boeing chairman, president and CEO Jim McNerney said in a statement: "The safety of passengers and crew members who fly aboard Boeing airplanes is our highest priority. Boeing is committed to supporting the FAA and finding answers as quickly as possible. The company is working around the clock with its customers and the various regulatory and investigative authorities. We will make available the entire resources of The Boeing Company to assist. We are confident the 787 is safe and we stand behind its overall integrity.  We will be taking every necessary step in the coming days to assure our customers and the traveling public of the 787's safety and to return the airplanes to service. Boeing deeply regrets the impact that recent events have had on the operating schedules of our customers and the inconvenience to them and their passengers."