By ANDY PASZTOR
Feb. 21, 2015 10:28 p.m. ET
U.S. air-safety regulators and aviation industry officials continue to clash over reducing fuel-tank explosion risks on some widely used cargo jets, seven years after such federal fixes were mandated for some 3,000 Boeing and Airbus passenger planes.
The Federal Aviation Administration on Friday released its latest proposal requiring modification of nearly 150 older cargo aircraft to combat hazards of vapors inside fuel tanks igniting on the ground or in the air. Projected to cost U.S. operators of these Boeing 757 cargo models as much as $380,000 a plane for the most extensive fixes—and potentially encompassing many more 757 models world-wide—the initiative aims to ensure the safety of the 757 cargo fleet eventually will be comparable to passenger jets in terms of fuel-tank flammability.
The dispute, under way for years, is one of the last controversial regulatory issues stemming from the fuel-tank explosion that destroyed TWA Flight 800 over Long Island Sound in 1996, killing all 230 people aboard. The accident prompted a flurry of FAA electrical wiring-related directives spanning all commercial aircraft, including a 2008 mandate to install nitrogen-gas-generating equipment on most Boeing and Airbus passenger jet. Much of the safety work on passenger jets has been completed.
So-called inerting systems reduce oxygen levels inside main fuel tanks to prevent a stray spark or short-circuit—originating inside or outside the tanks—from igniting volatile vapors.
However, in 2008, the agency exempted cargo carriers from those nitrogen-inerting requirements. Four years later, the FAA initially sought to reduce the vulnerability of 757 cargo planes to fuel-tank explosions, but its proposal stalled in the face of industry opposition. Now, FAA officials are again demanding that U.S.-registered 757 cargo jets phase in such inerting systems, or operators can opt for less-expensive solutions that would relocate certain wiring and follow up with periodic inspections.
The alternative solutions, which cost a fraction of installing inerting systems or swapping out main fuel-tank measuring devices, weren’t part of the earlier proposal. The latest proposal also stretches out certain anticipated compliance deadlines. As a result, the FAA is extending the period for public comment.
In an unusual twist, the FAA’s current strategy is to accept alternative fixes that mean a slightly higher level of risk for cargo carriers, versus passenger jets.
The agency explained that “it normally does not differentiate between the safety requirements or corrective action” imposed on the two parts of the industry. But after reviewing the original cost estimates and earlier industry comments, the FAA in this case proposed what it called “less costly risk reduction on cargo airplanes.” The document, however, emphasized that option “does not provide a sufficient level of risk reduction for passenger operations.”
The FAA, though, reiterated that some modifications are necessary for 757 cargo models because a pre-existing electrical problem inside a fuel tank, combined with a single additional failure in related wiring or equipment, can be “reasonably anticipated to occur” more often than allowed under agency rules. Under those scenarios, the risk of a catastrophic event “is in excess of the FAA’s threshold,” according to the agency.
Still, large portions of the industry remain opposed, arguing in previous comments to the 2012 proposal that any 757 fuel-tank fixes are unnecessary, costly and otherwise burdensome. The disagreement highlights the political and economic challenges regulators face as they seek to steadily raise the safety bar for a U.S. airline industry that suffered its last fatal passenger jet crash in February 2009.
Chicago-based plane maker Boeing Co., as well as cargo carriers FedEx Corp. and United Parcel Service Inc., have contended the FAA needs to recalculate its risk and cost assessments.
Boeing has told the agency the statistical likelihood of a fuel-tank explosion on cargo planes is significantly less than one in a billion flight hours. As part of the standoff with the FAA, the company hasn’t provided detailed technical backup for less-sweeping fixes.
Boeing couldn’t immediately be reached for comment.
In the end, the FAA concluded again that new safeguards are necessary for each 757 cargo jet to prevent possible “fuel tank explosions and consequent loss of the airplane.”
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