On Jul. 23, the U.S. aviation regulator proposed mandatory safety measures designed to prevent the accumulation of ice inside the pipes of the fuel systems in certain Boeing 777 airplanes, according to a posting on its website.

The Federal Aviation Administration (FAA) proposed these new measures in response to a British Airways accident last year and would require Boeing install redesigned cooling systems on some of its jets with Rolls-Royce made engines by January 2011.

The accumulation of ice can "result in an unacceptable engine power loss, and loss of control of the airplane," the FAA said in its proposal.

"The conditions that seem to have led to the British Airways flight 38 accident are rare to start with, and the non-normal procedures we have in place will serve to minimize the effects these conditions will have on airplanes in flight until the new FOHEs (fuel-oil heat-exchangers) are installed," a Boeing spokeswoman said.

There are about 220 Rolls-Royce-powered 777s in circulation, of which 50 operate in the United States and are therefore affected by the FAA's proposal, Boeing said.

An FAA spokesman was not immediately available for comment.

In January 2008, British Airways flight 38 slammed into the ground at London's Heathrow International Airport when both of the plane's engines reduced their thrust unprompted by the pilots. All passengers survived the incident.

The deadline for comments on the FAA's proposal is Aug. 24.