THE US Federal Aviation Administration has issued an emergency directive, warning of problems in the latest Boeing 737 MAX aircraft that could lead to pilots losing control of the planes.

The airworthiness directive covers all 737-8 and 737-9 aircraft and is similar to a service bulletin issued by Boeing, after the manufacturer conducted an analysis in the wake of the fatal Lion Air crash on October 29.

The aircraft are not used by Australia’s two major airlines, Qantas and Virgin Australia.

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The directive states that, if the “angle of attack” information received by the flight control system is too high, there is potential for repeated nose-down commands because the system believes the aircraft is going to go into an aerodynamic stall.

“This condition, if not addressed, could cause the flight crew to have difficulty controlling the airplane, and lead to excessive nose-down attitude, significant altitude loss, and possible impact with terrain,” the directive states.

“We are issuing this AD (airworthiness directive) because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

“Due to the need to correct an urgent safety of flight situation, good cause exists to make this AD effective in less than 30 days.”

The AD requires flight crew to comply with a runaway stabiliser procedure in the Boeing operating procedures manual.

This includes disengaging the autopilot and controlling the airplane pitch attitude with the control column and main electric trim.

The AD adds to the questions surrounding the Lion Air tragedy that claimed the lives of 189 passengers and crew.

Indonesian crash investigators have confirmed the 737 in the crash had technical faults on four flights previous to the one in which it plummeted into the sea shortly after take-off from Jakarta.

These included erroneous speed and altitude data that prompted a flight operated the day before the crash to go into a dive that frightened passengers and a made them sick.

The pilot of the flight requested a return to Denpasar but the situation corrected itself and he elected to continue to Jakarta.

Lion Air said it attended to the problem in accordance with Boeing procedures.