The Federal Aviation Administration (FAA) has ordered the replacement of pitot tubes on Airbus A330s of the type suspected of playing a role in the crash of Air France Flight 447 in June.

The FAA said in a notice published in the Federal Register that U.S. airlines operating A330s must replace within 120 days at least two of the three installed pitot tubes made by Thales. The approved replacement airspeed sensors are made in North Carolina by Goodrich.

The order affects 43 U.S. registered A330s: 32 operated by Northwest Airlines, now part of Delta Air Lines; and 11 operated by US Airways. Both air carriers had already begun replacing the older Thales pitot tubes. They must now replace those tubes with Goodrich-made pitot tubes.

The FAA order follows issuance of a similar European Aviation Safety Agency (EASA) airworthiness directive on Aug. 31 to replace the Thales sensors with Goodrich pitot tubes. FAA officials had been waiting for the EASA to act first since the airliners are made in Europe.

"We are issuing this AD to prevent airspeed discrepancies, which could lead to disconnection of the autopilot and/or auto-thrust functions, and reversion to flight control alternate law and consequent increased pilot workload. Depending on the prevailing airplane altitude and weather, this condition, if not corrected, could result in reduced control of the airplane," according to the FAA notice.

"We have reviewed the numerous air-speed anomalies recently reported," said the notice. "We have determined that an unsafe condition exists."

The EASA AD affects 200 Airbus A330/A340 aircraft currently outfitted with the older Thales pitot probes.

EASA's AD is intended as a precautionary measure in the wake of the June 1 loss of Air France Flight 447, an Airbus A330, flying from Rio de Janeiro to Paris, killing all 228 aboard. The accident remains under investigation, but air safety investigators found through automated maintenance data transmissions sent from the doomed aircraft that the Thales pilot tubes on the ill-fated jetliner had not worked properly as the airliner traveled through a severe storm over the Atlantic Ocean.

The AD, which started out as a recommendation from Airbus, is based on pitot probe performance data that was analyzed by EASA.

Meanwhile, BEA accident investigators still cannot explain why the Air France A330 went down and need more money and resources to search for the aircraft's flight data and cockpit voice recorders, according to Paul-Louis Arslanian, head of France's Bureau of Investigation and Analysis, or BEA.

He said a third, more meticulous search for plane debris and the flight recorders, should begin before the end of the year, but could cost tens of millions of euros (dollars). The third phase would involve sending deep-diving sonar-equipped underwater robots to the relatively unexplored seabed, up to 4,000 metres below the surface.

"We are making progress and will make more progress, but this will take time," he told journalists in Paris. "It takes a year and a half, being responsible and reasonable, in order to make progress and ensure that we've run through all of the questions."

Arslanian said Airbus has offered to help fund the efforts, but more commitments are needed. "We have to mobilize resources. It's not only having promises for money, we need to know who will contribute financially and how," he said.

Some of the relatives of the crash victims have already begun to point the finger at the Thales pitot tubes, which they say were faulty and to blame for the deaths. In particular, they have alleged that Airbus and Air France knew about longstanding concerns over the A330's pitot tubes but had failed to replace them.

Relatives of Brazilian victims of the Air France crash have asked the Brazilian government to open a criminal investigation into the disaster, according to press reports.

The investigation should "define penal responsibilities" because Air France ignored "indications of diverse failures" in the aircraft's controls, an association of relatives of the victims said.

Nelson Faria Marinho, the head of the association, complained that the probe was being conducted by France's BEA with no input from the Brazilians.

"We are asking the Brazilian authorities to follow this investigation and open a criminal process because a crime has been committed," he told a Brazilian state news agency.